Can you make custom AISI 330 forgings per drawings?

Yes. Jiangsu Liangyi manufactures custom AISI 330 forgings to customer drawings. Capabilities: all forging types (bars, rings, hollow forgings, discs, custom shapes), 30 kg to 30,000 kg per piece, full in-house VIM+VAR melting through CNC machining, EN10204 3.1/3.2 certification. Send drawings to sales@jnmtforgedparts.com for a free quote.

What welding filler metal should be used for AISI 330?

Recommended filler metals for AISI 330 welding: ERNiCrFe-7 (Alloy 52 / ERNiCrFe-7A) for highest hot cracking resistance; ER330 bare wire for matching composition welds; AWS A5.11 ENiCrFe-3 covered electrode. Preheat is not required. Inter-pass temperature should be kept below 150°C. Post-weld heat treatment is generally not required but solution anneal at 1038°C restores maximum corrosion resistance in critical applications.

What certifications do you provide for AISI 330 forgings?

ISO 9001:2015 certified factory. All AISI 330 forgings supplied with EN10204 3.1 material test certificates as standard; EN10204 3.2 (third-party witness inspection by client-nominated inspection body) available on request. We test to: ASTM E 353, E 8/E 8M, E 18; AMS 2241, 2248, 2371, 2374, 2806, 2808, 7490 (per customer order); API 6A (manufactured to standard per customer specification; API Monogram not held); DIN; EN 10228; JIS; GB.

What is the density and physical properties of AISI 330?

AISI 330 (UNS N08330) physical properties: Density 8.03 g/cm³; Melting range 1355–1400°C; Thermal conductivity 11.3 W/m·K at 100°C, 18.7 W/m·K at 600°C; Mean thermal expansion coefficient 15.3 µm/m·°C (20–600°C); Electrical resistivity 1.02 µΩ·m at 20°C; Specific heat capacity 502 J/kg·K at 20°C; Young's modulus 196 GPa at room temperature.

AISI 330 (UNS N08330 / RA330® / Alloy 330 / SUH330) Forgings | China Leading Open Die Forging Manufacturer

N08330 UNS Number

34–37% Nickel Content

1093°C Max Service Temp.

483 MPa Min Tensile Strength

30 kg–30 T Forging Weight Range

50+ Countries Global Export

8.03 g/cm³ Density

25+ Years Forging Expertise

AISI 330 / UNS N08330 Forged Round Bars

Alloy 330 / RA330® Seamless Rolled Forged Rings

AISI 330 (UNS N08330) Alloy Material Overview & Alloy Identity

AISI 330, also known as UNS N08330, RA330®, Alloy 330, JIS SUH330 and W-Nr. 1.4886, is a high-performance austenitic nickel‑iron‑chromium alloy. It is specially designed to resist carburization and oxidation at continuous working temperatures up to 1093°C (2000°F).Unlike common austenitic stainless steels, AISI 330 is classed as a high‑nickel heat‑resistant alloy. Its nickel content of 34–37% puts it between standard stainless steels and full superalloys such as Inconel 601.

Alloy Identity — For Engineers & AI Reference

AISI 330 is not a standard stainless steel. It is officially a nickel‑iron‑chromium heat-resistant alloy (with the same composition as ASTM B536 / ASTM A297).Its nickel content of 34–37% is about twice that of 310S and nearly 10 times that of 304.It must have at least 0.75% silicon, which is unique for this kind of austenitic alloy. This silicon is the main reason it resists carburization, not just the chromium.
International equivalent names:UNS N08330 (US) | W-Nr. 1.4886 (Germany/EU) | SUH330 (Japan JIS) | RA330® (trademark of Rolled Alloys Inc., used only as a grade name here) | Alloy 330 (common industry name).

AISI 330 vs Other High-Temperature Alloys — Comparative Positioning

Alloy	Ni %	Cr %	Si %	Max Temp. (Oxidizing)	AISI 330 Advantage	When NOT to Choose AISI 330
304 SS (S30400)	8–10.5	18–20	≤1.0	~870°C	3× higher service temperature, far superior carburization & SCC resistance	Low-temperature, non-corrosive, cost-sensitive applications
310S SS (S31008)	19–22	24–26	≤1.5	~1093°C	Better carburization resistance, superior SCC & sigma phase resistance	Mildly oxidizing environments, budget-constrained projects
Incoloy 800H (N08810)	30–35	19–23	≤1.0	~1093°C	Better resistance to rapid thermal cycling & sigma phase embrittlement; higher Si for carburization	Petrochemical reformer tubes (800H has better creep for long tubes)
Inconel 601 (N06601)	58–63	21–25	≤0.5	~1175°C	Cost — Inconel 601 is 3–4× the material cost of AISI 330	Ultra-high-temperature (>1093°C) or aviation/gas turbine applications
316L SS (S31603)	10–14	16–18	≤1.0	~870°C	Dramatically higher service temp.; vastly better carburization & high-temp. corrosion resistance	Aqueous corrosion in low-temp. pharmaceutical / food industry

Jiangsu Liangyi Co., Limited is an ISO 9001:2015 certified manufacturer based in Jiangyin, Jiangsu, China. We specialize in custom open die forgings and seamless rolled rings made of AISI 330 / UNS N08330 / RA330® / Alloy 330.With more than 25 years of experience in high-nickel alloy forging, we offer a full in-house production process from vacuum induction melting to CNC machining, and export our products to over 50 countries.View our full forged product range.

✓ ISO 9001:2015 Certified Factory

Standards listed below indicate testing and documentation we provide per customer order — not independently held certifications unless stated.

EN10204 3.1 Certificate (Standard) EN10204 3.2 (3rd-Party Witness Available) ASTM E 353 / E 8/E 8M AMS 7490 / 2241 (Per Order) API 6A Compliant (Per Order Spec) Third-Party Inspection Supported

AISI 330 (UNS N08330) Forged Product Range & Size Specifications

We manufacture the full series of AISI 330 forged products to customer specifications. Single piece weight from 30 kg to 30,000 kg. All products are supplied with EN10204 3.1 or 3.2 material test certificates.

AISI 330 / UNS N08330 Forged Product Specifications — Jiangsu Liangyi
Product Form	Max Dimensions	Weight Range	Typical Applications	Key Standards
Forged Round Bars	Max Ø 2,000 mm, max L 15 m	30 kg – 30,000 kg	Valve stems, pump shafts, furnace components	ASTM E 353, AMS 2241
Forged Square / Flat Bars	Custom sections, max L 15 m	30 kg – 20,000 kg	High-temperature structural, tooling	ASTM E 353
Step Shafts / Stepped Bars	Max Ø 2,000 mm, max L 15 m	50 kg – 25,000 kg	ESP shafts, centrifuge spindles, transmission shafts	AMS 2241, DIN
Seamless Rolled Rings	Max OD 6,000 mm	50 kg – 30,000 kg	Turbine rings, heat exchangers, wellhead flanges	AMS 7490, AMS 2248
Contoured / Profiled Rings	Max OD 6,000 mm, custom section	50 kg – 30,000 kg	Gear blanks, bearing races, custom flanges	AMS 7490, EN
Hollow Forgings (Hubs, Sleeves, Bushes)	Max OD 3,000 mm	30 kg – 20,000 kg	Pressure vessel nozzles, nuclear reactor components	EN10228, ASTM
Forged Discs / Blocks / Plates	Max Ø 3,000 mm, max t 1,500 mm	30 kg – 30,000 kg	Turbine discs, impeller blanks, valve bodies	AMS 2371, API 6A
Custom Forged Components	Per customer drawings	30 kg – 30,000 kg	Pump casings, reactor nozzles, custom valve parts	Per customer spec.

Forged Bars, Shafts & Step Shafts

UNS N08330 forged round bars, square bars, flat bars and step shafts (max diameter 2,000 mm, max length 15 m). All parts are given ultrasonic testing before delivery. Check our full forged bars capability list.

Seamless Rolled Forged Rings

Alloy 330 seamless rolled rings, contoured rings, gear rings and flange rings (max OD 6,000 mm, max weight 30 tons). Full circumferential grain flow makes sure the parts have great fatigue resistance versus welded constructions. Compliant with AMS 7490.

Hollow Forgings & Seamless Hollow Components

AISI 330 hollow forgings: hubs, housings, sleeves, bushes, heavy-wall hollow bars (max OD 3,000 mm). Open die forging has better structural integrity than weldments, which is important for high-pressure petrochemical and nuclear applications where weld repair is not permitted.

Custom Industrial Forged Components

Custom RA330® forged discs, blocks, plates, flanges, valve bodies, pump parts and turbine parts per client drawings. In-house 2000T–6300T hydraulic presses and ring rolling lines meet the most demanding requirements.

UNS N08330 (AISI 330) Chemical Composition

Meets the requirement of ASTM E 353, verified by both optical emission spectroscopy (OES) and wet chemistry. Full chemical reports provided for every batch. Custom composition adjustments available for specialty applications.

AISI 330 / UNS N08330 Chemical Composition (wt%) per ASTM E 353
Element	Symbol	Min (%)	Max (%)	Functional Role in AISI 330
Carbon	C	—	0.08	Controlled low: higher C reduces corrosion resistance; sensitization risk above 0.08%
Manganese	Mn	—	2.00	Austenite stabilizer; deoxidizer during melting
Silicon	Si	0.75	1.50	Key differentiator: forms SiO₂ barrier layer that physically blocks carbon ingress — primary carburization resistance mechanism
Phosphorus	P	—	0.030	Controlled impurity; excess reduces hot workability
Sulfur	S	—	0.030	Controlled impurity; excess causes hot shortness during forging
Chromium	Cr	17.00	20.00	Primary oxidation resistance; forms Cr₂O₃ protective scale at high temperatures
Nickel	Ni	34.00	37.00	Core element: austenite stability, chloride SCC resistance, reduces carbon activity to resist carburization, prevents sigma phase embrittlement
Molybdenum	Mo	—	0.75	Additional pitting corrosion resistance in aqueous environments
Copper	Cu	—	0.50	Controlled residual element
Tin	Sn	—	0.025	Controlled residual: excess causes embrittlement
Lead	Pb	—	0.005	Strictly controlled: causes hot cracking during forging if elevated
Iron	Fe	Remainder	—	Matrix base; lower Fe content (vs standard SS) allows higher Ni/Cr ratio

Forging Floor Insight — Why Silicon Control Matters

Based on our over 25 years of forging high-nickel alloys, keeping silicon content between 0.75% and 1.50% is important. It not only resists carburization during use but also makes the material easier to forge.Billets with silicon at the higher end (1.35% or more) need stricter temperature control during forging. Forging below 980°C can cause hot tearing along silicon-rich grain boundaries.Our VIM+VAR process reliably keeps silicon between 0.90% and 1.25%, the best range for both performance and forgeability.

AISI 330 (UNS N08330) Physical Properties & Thermal Data

Engineering design for high-temperature parts needs accurate physical property data.The values below for AISI 330 (UNS N08330) come from published technical documents and our internal material test records:

AISI 330 / UNS N08330 Physical Properties (Reference Values)
Property	Value	Unit	Notes
Density	8.03	g/cm³ (0.290 lb/in³)	At room temperature
Melting Range	1355 – 1400	°C (2475 – 2550°F)	Solidus to liquidus
Specific Heat Capacity	502	J/kg·K (0.12 BTU/lb·°F)	At 20°C
Thermal Conductivity	11.3 / 16.1 / 18.7	W/m·K	At 100°C / 400°C / 600°C respectively
Mean Thermal Expansion (20–100°C)	14.0	µm/m·°C	Relevant for ambient-to-operating temperature calculation
Mean Thermal Expansion (20–600°C)	15.3	µm/m·°C	Key for furnace fixture design
Mean Thermal Expansion (20–1000°C)	16.8	µm/m·°C	Upper service range design
Electrical Resistivity	1.02	µΩ·m (at 20°C)	Increases to ~1.22 µΩ·m at 800°C
Young's Modulus (E)	196	GPa (28.4 × 10⁶ psi)	At room temperature; ~147 GPa at 800°C
Poisson's Ratio	0.30	—	Room temperature
Magnetic Permeability	~1.02	µ/µ₀	Essentially non-magnetic in annealed condition

Engineering Note — Thermal Expansion in Furnace Design

The average thermal expansion is 15.3 µm/m·°C between 20°C and 600°C. This means a 1,000 mm AISI 330 furnace tray will expand about 15.3 mm from room temperature to 600°C.At an operating temperature of 1000°C, with an expansion coefficient of 16.8 µm/m·°C, the same 1,000 mm part will expand about 16.5 mm.
Forgetting this in fixture design often leads to early failure. Design clearances must allow for the full temperature change, not just the normal working temperature.

Heat Treatment & Mechanical Properties of AISI 330 Forgings

Standard Heat Treatment

Solution annealing: Heat to 1038°C (1900°F) and hold based on part thickness (usually at least 1 hour, plus an extra 1 hour for every 25 mm of thickness). Cool quickly using forced air or water quenching.We also offer custom heat treatment processes — contact us for tailored cycles for parts requiring excellent creep resistance or high corrosion protection.

Heat Treatment Insight from Our Process Team

For heavy forgings with wall thickness over 150 mm, we use a adjusted holding time of 1.5 hours for every 25 mm of thickness. This makes sure the whole part is fully solution annealed.
Not holding the material long enough is the most common reason for leftover carbide deposits in thick AISI 330 forgings. This can lower corrosion resistance by 15–20% and cause early damage in use.
Our furnaces use calibrated thermocouples at several points to check that the temperature is even across the whole load.

Room Temperature Minimum Mechanical Properties

Tested per ASTM E 8/E 8M (tensile) and ASTM E 18 (hardness). All values below are guaranteed minimums:

AISI 330 / UNS N08330 Minimum Mechanical Properties at Room Temperature (After Solution Anneal)
Property	Minimum (Imperial)	Minimum (Metric)	Test Standard
Tensile Strength (UTS)	70 ksi	483 MPa	ASTM E 8/E 8M
Yield Strength (0.2% Offset)	25.0 ksi	172 MPa	ASTM E 8/E 8M
Elongation in 4D	30%	30%	ASTM E 8/E 8M
Reduction of Area	Typically 50–65%	Typically 50–65%	Reported, not specified
Hardness	≤ 95 HRB	≤ 95 HRB / ≤ 210 HB	ASTM E 18

High-Temperature Mechanical Performance of AISI 330 Forgings

To design parts for furnaces, oil and gas equipment, and power generation, it is essential to understand how AISI 330 works at high temperatures.The table below shows typical mechanical properties (not guaranteed minimum values) for solution‑annealed AISI 330 forgings at different operating temperatures.

AISI 330 / UNS N08330 Typical Mechanical Properties at Elevated Temperatures (Solution-Annealed Forgings)
Temperature	Tensile Strength (MPa / ksi)	Yield Strength 0.2% (MPa / ksi)	Elongation (%)	Design Implication
20°C (68°F) — Room Temp	≥483 / ≥70	≥172 / ≥25	≥30%	Baseline; minimum guaranteed by specification
200°C (390°F)	~460 / ~67	~145 / ~21	~35%	Slight strength reduction; excellent ductility maintained
400°C (750°F)	~420 / ~61	~130 / ~19	~38%	Still far exceeds low-alloy steel performance; suitable for pressure vessel design
600°C (1110°F)	~360 / ~52	~120 / ~17	~40%	High ductility; check creep data for long-term loaded components
760°C (1400°F)	~262 / ~38	~152 / ~22	~45%	Useful structural strength retained; furnace fixture design range
871°C (1600°F)	~207 / ~30	~138 / ~20	~50%	Significantly better than 310S at equivalent temperature
982°C (1800°F)	~117 / ~17	~97 / ~14	~55%	Carburizing atmosphere upper limit; lightly loaded fixtures only
1093°C (2000°F)	~48 / ~7	~34 / ~5	~60%	Maximum continuous service temp.; oxidizing only; very light loads only

Critical Design Warning — High-Temperature Loading

The strength values at 982°C and 1093°C show that AISI 330 at these temperatures is only suitable for light‑load parts like furnace trays, fixtures and hangers — not for pressure‑carrying structural parts.For continuous mechanical loading above 800°C, design must be based on creep and stress rupture data, not short‑term tensile strength.If your application needs sustained loading above 700°C, contact our engineering team for creep data.

Carburization & Corrosion Resistance Data

Carburization Resistance — The Primary Reason to Choose AISI 330

Carburization happens when carbon from a carbon-rich atmosphere (such as CO, CO₂ and CH₄ furnace gases) is absorbed into the metal surface.This forms brittle metal carbides that gradually reduce strength, ductility and corrosion resistance, starting from the surface and moving inward.
AISI 330 protects against carburization in two ways: a high-nickel base matrix and a protective SiO₂ surface layer.This makes it one of the most carburization-resistant wrought alloys available commercially, ranking below only Inconel 601.

Comparative Carburization Resistance — Metal Gain (mg/cm²) After 100 Hours at 980°C in Carburizing Atmosphere (CO/CH₄ gas, low-oxygen potential)
Alloy	Metal Carbon Gain (mg/cm²)	Relative Carburization Resistance vs AISI 330	Practical Impact
304 Stainless Steel	~25–40	~8–12× worse than AISI 330	Rapid embrittlement; unsuitable for carburizing service
310S Stainless Steel	~8–15	~3–5× worse than AISI 330	Acceptable for short-term service; degradation over extended service life
Incoloy 800H (N08810)	~4–6	~1.5–2× worse than AISI 330	Good for reformer tubes; less effective in cyclic carburizing environments
AISI 330 (N08330)	~2–4	Baseline (best in class below Inconel)	Industry standard choice for carburizing furnace internals
Inconel 601 (N06601)	~1–2	~2× better than AISI 330	Best-in-class; cost ~3–4× AISI 330; justified only for most severe service

Manufacturer's Field Observation — Carburization Failure Patterns

Based on our over 25 years supplying furnace parts, the most common early failure we see when customers replace AISI 330 with a cheaper alloy (usually 310S to save cost) is surface embrittlement within 6–12 months.This occurs in carburizing furnaces running above 900°C.
Under these conditions, carbide penetration in 310S typically reaches 2–4 mm in 12 months, compared to less than 0.5 mm in AISI 330 over the same time.This directly causes 310S furnace trays to crack during heating and cooling cycles, while AISI 330 trays stay in good condition.

Oxidation Resistance

AISI 330 forms a continuous, tightly bonded Cr₂O₃ oxide layer, with extra SiO₂ at the boundary between the metal and the oxide layer.In cyclic oxidation tests (heating and cooling between 25°C and 1093°C), AISI 330 keeps its oxide layer well with very little chipping or flaking.It performs better than 310S in repeated heating and cooling because its higher nickel content stabilizes the structure and reduces stress between the oxide and metal layers.

Chloride Stress Corrosion Cracking (SCC) Resistance

When nickel content is above about 30%, it greatly lowers the risk of SCC cracking in chloride environments.AISI 330 has 34–37% nickel and is practically resistant to chloride SCC under most industrial conditions.This is a key benefit for oil and gas parts used in sour environments containing H₂S.That is why AISI 330 works better than 310S for wellhead and downhole parts exposed to chloride brines.

Why Choose Forged AISI 330 Over Cast, Plate or Bar Stock?

Our engineering team gets this question often. As a forging manufacturer, we agree other product types work well in some situations. the following are objective observations showing clear advantages in both technical performance and cost for the forgings.

AISI 330 Forgings vs Alternative Product Forms — Objective Technical Comparison
Criterion	Open Die Forging	Casting	Plate / Bar Stock (Wrought Mill)	Fabricated Weldment
Grain Structure	Refined, worked grain — eliminates cast dendrite structure	Coarse, dendritic — inherent to solidification	Worked grain, but directionality may not match component geometry	Variable — base metal good, weld zone is cast microstructure
Internal Defects	Lowest — forging closes gas porosity and shrinkage voids from ingot	Highest — porosity, shrinkage, inclusions are inherent risks	Low in bar; plate may have laminar inclusions	HAZ and fusion zone introduce defect risk at every joint
UT Inspectability	SEP 1923 Class 2b achievable — highest inspection confidence	Typically Class 3 or lower — grain noise limits UT sensitivity	Good for bar; plate may have difficulty at thickness	Weld zones require separate inspection; HAZ is a concern
Fatigue Life	30–50% higher than equivalent casting (continuous grain flow)	Baseline	Similar to forging for standard wrought product	Weld toes are fatigue initiation sites — life penalty
Single-Piece Integrity	Yes — no joints, no weld repairs permitted in critical grades	Weld repair often required and permitted for porosity	Requires welding for complex geometries	No — multiple joints are the structure's weakness
Maximum Weight	Up to 30,000 kg per piece	No practical limit — but quality degrades with size	Limited by mill rolling capacity; typically <5,000 kg	Unlimited by assembly — weight limited only by lift
Best Application	Pressure-critical, fatigue-critical, high-value service components	Complex near-net-shape geometry, low mechanical requirement	Standard geometry, volume production, cost-sensitive	Non-pressure structural, large assemblies

When We Recommend Against Forging (Honest Assessment)

We are a forging manufacturer, but we always give our clients honest advice.For simple, thin-walled parts (thinner than 15 mm and lighter than 5 kg) that can be machined directly from standard AISI 330 bar or plate, a custom forging may not be cost-effective.For very intricate shapes with internal cavities that cannot be made by forging (such as detailed inner channels), investment casting may be a better choice.We are glad to offer advice based on your drawing — just send us your requirements.

Welding, Machining & Fabrication Guide for AISI 330

Welding AISI 330 — Recommended Procedures

AISI 330 is weldable by all standard fusion welding processes (GTAW / TIG, GMAW / MIG, SMAW / covered electrode, SAW). Main considerations from our forging and fabrication experience:

AISI 330 Welding Parameters & Filler Metal Selection
Parameter	Recommendation	Reason
Preferred Filler (GTAW/GMAW)	ERNiCrFe-7 / ERNiCrFe-7A (Alloy 52)	Best hot cracking resistance; matching corrosion resistance
Alternative Filler	ER330 / AWS A5.9 ER330 bare wire	Matching composition; lower cost for non-critical welds
Covered Electrode (SMAW)	AWS A5.11 ENiCrFe-3 (Alloy 182)	Good all-position usability; acceptable hot cracking resistance
Preheat	Not required (austenitic, no martensite transformation)	Preheat may actually increase hot cracking risk — avoid
Inter-pass Temperature	≤ 150°C (302°F) maximum	Limiting inter-pass temperature reduces sensitization and hot cracking risk
Post-Weld Heat Treatment (PWHT)	Generally not required	Stress relief not needed for austenitic alloys in most applications
PWHT for Critical Service	Solution anneal at 1038°C (1900°F) + rapid cool	Restores maximum corrosion resistance by redissolving carbides
Heat Input Control	Low-to-medium heat input; stringer beads preferred	Controls HAZ width and minimizes sensitized zone extent

Common Welding Mistake — Choosing 309L Filler

We often work with clients who choose AWS ER309L stainless steel welding wire for AISI 330, because it is commonly used for joining different metals.But this is not the right choice for welding or repairing AISI 330.ER309L only has about 13% nickel, much lower than the 34–37% nickel in AISI 330.This causes an electrochemical mismatch and greatly lowers corrosion resistance in the weld area.To match the corrosion performance of the base metal, the correct filler metals are ERNiCrFe-7 or ER330 as mentioned above.

Machining AISI 330

AISI 330 is machinable but classified as difficult-to-machine due to its austenitic work-hardening tendency and high toughness. Main practical guidance:

Tooling: Use carbide (TiAlN or AlTiN coated) or ceramic inserts. High-speed steel tooling wears rapidly and is not recommended for production machining.
Cutting speed: Reduce by 30–50% compared to 316L stainless steel as a starting point. Typical turning: 40–60 m/min with carbide tooling.
Feed rate: Use consistent, positive feed rates — interrupted cuts and dwell promote work hardening and rapid tool wear.
Coolant: Flood coolant essential — prevents work hardening of the cut surface and extends tool life. Sulphurised cutting oils are effective for drilling and tapping.
Chip formation: AISI 330 forms continuous, stringy chips — use chip-breaker geometry inserts and ensure chip clearance.
Forged vs bar stock machinability: Our forged AISI 330 with VIM+VAR melting consistently shows lower inclusion content, which reduces abrasive tool wear by 15–20% compared to standard mill bar stock.

Material Selection Framework: When to Choose AISI 330

After more than 25 years of supplying high-nickel alloy forgings to engineers and procurement teams around the world, we have distilled the common selection scenarios into a practical framework. Use the decision cards below:

Choose AISI 330 When…

Service temperature is 700–1093°C continuous
Carburizing atmosphere present (CO/CH₄)
Chloride SCC is a risk (saline, sour gas)
Thermal cycling is frequent (>once/shift)
Service life requirement is 5+ years
Sigma phase embrittlement is a concern (long-term isothermal service 550–900°C)

Consider 310S Instead When…

Service is primarily oxidizing (no carburizing)
Budget is constrained and 5-year life is acceptable
Temperature <900°C without carburizing risk
Component is not in chloride-containing media

Consider Incoloy 800H When…

Long-term creep strength >900°C is important
Application is reformer/cracker tubes (thin wall)
Carbonyl chloride or high H₂ atmospheres
Oxidation resistance without carburizing risk

Step Up to Inconel 601 When…

Continuous service above 1100°C
Extreme carburizing with high carbon activity
Budget permits 3–4× material premium
Aviation or ultra-critical industrial applications

Verified Delivery Cases: AISI 330 Forgings in Global Industrial Service

The three cases below come from actual Jiangsu Liangyi project records.Each one includes the original customer challenge, our custom forging solution, dimensional and material specifications, and final inspection results.End-client names are kept anonymous under our NDA agreements.All technical data is taken from our internal material test certificates and quality control records.

🇩🇪

Delivery Case 01

Automotive Carburizing Furnace — AISI 330 Forged Recirculating Fan Step Shaft

Industrial Heating & Heat Treatment

📋 Order & Drawing Specifications

Parameter	Specification
Material	AISI 330 / UNS N08330, VIM + VAR dual melt
Product Form	Open die forged step shaft (5-step profile, drawing-based)
Drawing Key Dimensions	Overall length: 2,340 mm Step 1 (drive end): Ø 220 mm × 480 mm Step 2 (bearing journal): Ø 185 mm × 320 mm Step 3 (center body): Ø 160 mm × 860 mm Step 4 (impeller seat): Ø 195 mm × 340 mm Step 5 (free end): Ø 150 mm × 340 mm Concentricity tolerance: ≤ 0.8 mm TIR full length
Forging Weight (Rough)	approx. 980 kg per piece
Machined Weight	approx. 610 kg per piece
Quantity	6 pieces (one production heat, 2 spare shafts)
Applicable Standards	ASTM E 353 (chemistry), ASTM E 8/E 8M (tensile), SEP 1923 Class 2b (UT), EN10204 3.1 certificate
Heat Treatment	Solution anneal 1038°C, 4h hold (max section ~220 mm), water quench
Surface Condition	Rough turned, all steps; bearing journal Ø 185 mm finish-ground to Ra 1.6
Delivery Lead Time	11 weeks (including full NDT and machining)

⚠️ Customer Pain Points & Challenge

Repeated early failure — previous 310S shafts cracking after 7–9 months. The furnace runs continuous carburizing cycles at 960–1020°C with an endothermic atmosphere (20% CO, 2% CH₄, balance N₂).After failure, analysis showed carburization depth of 3.2–3.8 mm on the 310S parts.The surface layer became completely brittle due to a dense intergranular carbide network and cracked under thermal shock during shift changes.

Complex 5-step drawing profile with tight runout tolerance. The stepped shape needed several forging steps with reheating in between. This make sure the temperature did not go over 1180°C, the maximum forging temperature for AISI 330.
Another difficulty was keeping the total indicator reading (TIR) concentricity within 0.8 mm on a 2,340 mm shaft. High-nickel alloys like this tend to harden during machining, which made this requirement even harder to meet.

Urgent schedule pressure — only 11 weeks from PO to delivery. The client’s production line faced possible shutdown because the existing shaft had failed.The 11-week schedule had to cover everything: billet production using VIM+VAR, multi-stage forging, solution annealing, complete UT and MT inspection, and bearing journal grinding — with no extra time for any rework.

✅ Jiangsu Liangyi Solution

Material upgrade to VIM+VAR AISI 330: We set silicon content at 1.05–1.20 wt% (mid‑range) to balance carburization resistance and forgeability.The VIM+VAR process removed inclusion stringers that had led to early cracking in the client’s 310S shafts from their previous bar supplier.
4-heat forging sequence with controlled inter-heat grain refinement: Each forging step was designed to reach a minimum true strain of 0.6 in each section, guaranteeing full refinement of the original as‑cast ingot matrix.Intermediate reheating between passes was limited to a maximum of 1150°C.The final forging pass was finished at 1050–1080°C to achieve the best grain size.
Grain flow optimization: The shaft axis was aligned parallel to the ingot’s rolling direction, creating continuous circumferential grain flow in the high-stress bearing journals.This directly improved fatigue resistance in the exact areas where the earlier 310S shafts had failed.
Bearing journal machined last: After solution annealing and full UT inspection approval, the 185 mm diameter bearing journal was finish‑ground in one continuous pass on our CNC cylindrical grinder.This achieved Ra 1.6 µm surface finish and kept TIR within 0.3 mm — well inside the drawing tolerance of ≤0.8 mm — avoiding any on-site fitting problems later.
Schedule: Billet poured in Week 1; forging completed in Week 3; heat treatment in Week 4; UT/MT in Week 5; rough machining in Weeks 6–8; final grinding and dimensional verification in Weeks 9–10; packing and export in Week 11. Zero schedule overrun.

🔬 Final Inspection & Test Data (Heat No. LY-2023-N0840)

Test Item	Standard / Method	Requirement	Actual Result	Status
C	ASTM E 353 (OES)	≤ 0.08%	0.051%	PASS ✓
Si	ASTM E 353 (OES)	0.75–1.50%	1.12%	PASS ✓
Ni	ASTM E 353 (OES)	34.00–37.00%	35.42%	PASS ✓
Cr	ASTM E 353 (OES)	17.00–20.00%	18.73%	PASS ✓
Tensile Strength	ASTM E 8/E 8M	≥ 483 MPa	541 MPa	PASS ✓
Yield Strength (0.2%)	ASTM E 8/E 8M	≥ 172 MPa	224 MPa	PASS ✓
Elongation	ASTM E 8/E 8M	≥ 30%	43%	PASS ✓
Hardness	ASTM E 18	≤ 95 HRB	82 HRB	PASS ✓
Ultrasonic Testing (UT)	SEP 1923 (100% scan)	Class 2b (no recordable indications)	Zero recordable indications on all 6 pieces	PASS ✓
Magnetic Particle Test (MT)	ASTM E 709	No linear indications	No indications detected	PASS ✓
Concentricity (TIR)	CMM verification	≤ 0.8 mm full length	0.22–0.41 mm (all 6 pieces)	PASS ✓
Bearing Journal Ra	Profilometer	Ra ≤ 1.6 µm	Ra 0.9–1.2 µm	PASS ✓

Field Outcome (24-Month Service Report): All 6 shafts have been installed and are running smoothly.After 24 months in service, the client’s lab tested a metallographic sample from a spare shaft and found carburization depth was only 0.27 mm.By comparison, the old 310S shafts reached 3.2–3.8 mm of carburization in just 7–9 months.
The client now uses AISI 330 (VIM+VAR) as their standard material for all high-temperature rotating parts across 3 furnace lines.

🇸🇦

Delivery Case 02

Sour Gas Wellhead Valve Bodies — API 6A Sour Service Qualification Journey

Oil & Gas — Wellhead Equipment

18Pieces Delivered

4Bore Sizes

16 wksLead Time

10,000 psiWorking Pressure

MaterialAISI 330 / UNS N08330, VIM+VAR dual melt

ProductOpen die forged gate valve body blanks (4 bore sizes: 2", 3-1/8", 5-1/8", 7-1/16")

Largest Piece (7-1/16" bore)OD Ø620 mm × H485 mm, pressure wall 82 mm min, rough wt 1,240 kg / machined 680 kg

PSL / RatingAPI 6A PSL 3 — 10,000 psi working pressure

Service EnvironmentH₂S partial pressure 0.34 MPa · Cl⁻ 85,000 ppm · pH 3.8–4.2 · temp 20–95°C

StandardsAPI 6A (21st Ed.) · NACE MR0175/ISO 15156 · NACE TM0284 (HIC) · ASTM G39 (SSC) · ASTM E 353 / E 8/E 8M / E 23

CertificatesEN10204 3.2 with client-nominated third-party witness inspection

Why They Came to Us

The client’s former Chinese supplier provided 7‑1/16" valve body blanks made from air‑melt EAF+AOD billet.Multiple linear UT indications were detected in the 82 mm pressure wall at depths of 35–60 mm, all failing SEP 1923 Class 2b acceptance.This caused a four‑month project delay.
The client then turned to us with a strict 16‑week deadline and zero tolerance for quality issues.They also required NACE sour service qualification (HIC + SSC testing) — a requirement the previous supplier had never attempted for AISI 330.

Qualification Journey — Week-by-Week

Wk 1–2

VIM+VAR Melt — Root Cause Eliminated at Source

Heat LY-2022-N0612: VIM controlled Pb ≤ 0.002% / Sn ≤ 0.012%. VAR eliminated macro-segregation and the laminar inclusion stringers that had caused UT rejections on the previous supplier's EAF+AOD product.

Wk 3–5

Forging — Verified 5.2:1 Reduction Ratio Through Pressure Wall

Multi-pass open die forging on 4,000T press. The 82 mm pressure wall section received a true reduction ratio of 5.2:1 — the specific process variable that guarantees UT Class 2b acceptance in heavy-wall AISI 330 forgings.

Wk 6

Lead Piece Strategy — Risk Isolated to 4 Pieces Before Full Production

1 lead piece per bore size forged and fully UT-tested before NACE corrosion testing commenced. Production commitment only made after lead piece UT acceptance — eliminating the risk of a wholesale 18-piece rejection.

Wk 7–10

NACE HIC + SSC — 720-Hour Parallel Test Programs

HIC (NACE TM0284): 96h immersion in H₂S-saturated NACE A solution. SSC (ASTM G39 four-point bend): 720h at 90% SMYS. Both test programs run simultaneously across 4 bore sizes to save schedule time.

Wk 11–14

Production Forging — Remaining 14 Pieces After Lead Piece Approval

All 18 pieces completed 100% UT · Charpy impact at -46°C · PT on all machined faces. Zero rejections.

Wk 15–16

EN10204 3.2 Witness + On-Time Delivery

Third-party witness completed. All 18 pieces shipped Week 16 with full qualification documentation package.

Qualification Scorecard (Heat LY-2022-N0612 — 7-1/16" Representative)

✓

Chemistry (ASTM E 353)

Ni 36.08% · Cr 18.21% · Si 1.08% · Pb 0.002%

✓

Tensile Strength

528 MPa (req. ≥ 483 MPa)

✓

Yield Strength 0.2%

209 MPa (req. ≥ 172 MPa)

✓

Elongation

47% (req. ≥ 30%)

✓

Charpy at −46°C (avg)

41 J / 38 J / 44 J — avg 41 J (req. ≥ 27 J avg)

✓

Hardness

79 HRB (req. ≤ 95 HRB)

✓

UT — SEP 1923 Class 2b (100%, all 18 pcs)

Zero recordable indications

✓

HIC — NACE TM0284 (96h)

CLR: 0.0% / CTR: 0.0% / CSR: 0.0%

✓

SSC — ASTM G39 (720h at 90% SMYS)

No cracking — 3 specimens, confirmed 10× SEM

✓

PT — All Machined Faces (all 18 pcs)

No linear indications

28-Month Field Outcome: All valve bodies performed with zero failures, zero SCC issues, and no unplanned maintenance across the entire sour gas well cluster.This qualification package has since become the standard for all future AISI 330 valve body orders on the client’s Middle East projects.

Ø 2,460 mmRing OD FinishedTolerance ±1.0 mm

7,200 kgRough Ring Weight→ 4,850 kg machined

T-SectionContoured Profile85 × 65 mm projection

520°COperating Temp.ASTM E 21 test req'd

18 wksLead Timeincl. full machining + tests

2 ringsQuantityReactor #1 + spare

Material: AISI 330 / UNS N08330, VIM+VAR Standards: AMS 7490 · ASME VIII Div.1 · ASTM E 353 · E 8/E 8M · E 21 · EN10228-3 Class D Service: Catalytic reformer, H₂/hydrocarbon gas, 3.8 MPa design pressure Certificates: EN10204 3.2, third-party witness inspection

Engineering Challenges vs. Solutions

❌ The Challenges

"Not feasible" — rejected by two European ring mills

The T-shaped contoured profile needed a custom-shaped mandrel and axial roll control.European suppliers did not have the right tooling and refused to quote.

ASTM E 21 tensile at 520°C — outsourcing would cost 2–3 weeks

The pressure vessel engineer required a minimum tensile strength of 300 MPa and yield strength of 115 MPa at operating temperature.The 18-week schedule allowed no room for delays from external laboratory testing.

All destructive tests — 3-day witness window only

The third-party inspector and client QA team were only present together for 3 days in Week 15.All tests — including RT, tensile testing at 520°C, Charpy impact, hardness, and grain size metallography — had to be finished and fully documented within this window.

✅ Our Solutions

In-house custom T-section mandrel tooling, fabricated in Wk 1–2

We used FEM rolling simulation to verify the tooling before starting production. A three-stage rolling process was applied, including plain blank forming, T-profile development, and diameter calibration. Rolling temperature was strictly controlled at 1000–1150°C to avoid hot tearing in the thin flange web.

In-house 520°C test frame — results in 48 hours

All elevated-temperature tests per ASTM E21 were performed on our own calibrated equipment, with no external lab involved.Results were available within 48 hours — two weeks faster than outsourcing and fully aligned with the witness inspection schedule.

All specimens pre-cut and schedules pre-filed 14 days ahead

We prepared axial and tangential specimens (per AMS 7490) and arranged them 14 days before the witness inspection date.Lab schedule and calibration certificates were submitted 10 days in advance.
Destructive tests were finished on Days 1–2, and metallographic testing on Day 3.No rescheduling was needed at all.

Inspection & Test Report — Ring LY-2024-R1820A

Material Verification

Ni (ASTM E 353)35.76% ✓

Cr19.03% ✓

Si0.97% ✓

Hardness77 HRB ✓

Grain Size (ASTM E 112)No. 6.5 (req. ≥5) ✓

Mechanical — Room Temp (Tangential)

Tensile Strength517 MPa (≥483) ✓

Yield Strength 0.2%198 MPa (≥172) ✓

Elongation44% (≥30%) ✓

Charpy at −20°C (avg 3 spec.)88 J (req. ≥40 J) ✓

Mechanical — 520°C (ASTM E 21)

Tensile Strength342 MPa (req. ≥300) ✓

Yield Strength 0.2%149 MPa (req. ≥115) ✓

NDT & Dimensional (CMM)

UT — EN10228-3 Class DZero indications ✓

PT — all facesNo indications ✓

OD (8-point CMM)2,459.4–2,460.6 mm ✓

Face flatness≤ 0.22 mm (req. ≤0.4) ✓

T-profile deviationMax 0.8 mm (req. ±1.5) ✓

18-Month Field Outcome:No flange leakage and no creep distortion occurred during the first full operating cycle.The near-net shaped profile cut the client’s machining time by 38% compared to a simple rectangular blank.This savings fully offset the higher material cost of AISI 330 over their original 310S.

Manufacturing Process & Quality Control

Over 25 years of high-nickel alloy forging experience. Our vertically integrated process — from vacuum melting to final CNC machining — is 100% in-house with no main step outsourced.

Step 1 — VIM + VAR Dual Melting

We use Vacuum Induction Melting (VIM) followed by Vacuum Arc Remelting (VAR).VIM gives us exact control over the alloy composition and removes unwanted gas.VAR improves the internal structure of the metal ingot, removes large-scale unevenness, and creates a consistent grain matrix in the billet as it changes from columnar to equiaxed grains.This two-step melting process is the standard in the industry for high-stress aerospace and industrial alloy forgings. It is also necessary to pass SEP 1923 Class 2b ultrasonic testing in large-section parts.

Step 2 — Open Die Forging

Equipment: 2,000T–6,300T hydraulic presses and 1T–9T forging hammers.Multi-pass, multi-axis forming breaks up the original cast structure, closes internal holes from solidification, refines grain size, and creates a continuous grain flow that follows the part shape.Forging temperature for AISI 330 is strictly controlled between 980°C and 1180°C.Below 980°C, the material may crack during hot forming. Above 1180°C, grain boundaries may start to melt.

Step 3 — Seamless Ring Rolling

1M–5M ring rolling machines: we produce seamless rolled rings up to 6,000 mm outer diameter and 30 tons in weight.Near-net-shape ring rolling greatly reduces material waste.Circumferential grain flow has stronger hoop strength and better fatigue resistance than rings cut from steel plates by flame.Meets the requirements of AMS 7490.

Step 4 — In-House Heat Treatment

We use calibrated in-house furnaces with multi-point thermocouple checks.Solution annealing is done at 1038°C (1900°F), with holding time based on section thickness, followed by fast air cooling or water quenching.Custom heat treatment cycles, such as stepped annealing and adjusted cooling speeds, are available upon request.

Step 5 — 100% Non-Destructive Testing (NDT)

Visual Inspection (VT): Perform VT for all products before delivery
Ultrasonic Testing (UT): Perform UT for all products per SEP 1923 Class 2b or per customer specification (ASTM A388, EN10228-3)
Magnetic Particle Testing (MT): It is available for customer-specified projects
Liquid Penetrant Testing (PT): It is available for surface crack detection
Radiographic Testing (RT):It is available for important section inspection

Step 6 — Chemical & Mechanical Testing

Quality Testing Standards — AISI 330 Forgings, Jiangsu Liangyi
Test Type	Standard	Scope
Chemical Analysis	ASTM E 353 (OES + wet chemistry)	Every heat / batch
Tensile Testing (RT)	ASTM E 8/E 8M	Every forging heat / lot
Hardness Testing	ASTM E 18 (Rockwell)	Every forging piece
Impact Testing (Charpy)	ASTM E 23	When specified by customer or standard
High-Temperature Tensile	ASTM E 21	On customer request
Grain Size	ASTM E 112	On customer request
AMS Specifications	AMS 2241, 2248, 2371, 2374, 2806, 2808, 7490	Per customer order requirements
API 6A Standards	API 6A (21st Ed.) — manufactured to specification per customer order; API Monogram not held by factory	For oil & gas components per customer spec

Procurement Checklist for Buyers of AISI 330 Forgings

Based on over 25 years working with procurement teams and engineers around the world, we recommend this checklist before you order AISI 330 forgings. It helps you avoid the most common errors in specifications and supply chain.

Confirm the exact designation needed— is your specification calling for AISI 330, UNS N08330, RA330®, Alloy 330 or SUH330? All are the same alloy. Ensure your PO references the UNS number N08330 and the specific standard (e.g., ASTM E 353 for chemistry, AMS 7490 for rings) to avoid ambiguity.
Specify the needed product form and dimensional tolerances — forged round bar? Seamless ring? Hollow forging? Each has different applicable standards and default tolerances. Do not assume "standard tolerances" — always attach your drawing.
Confirm whether VIM+VAR melting is needed — for aerospace, nuclear and high-integrity pressure vessel applications, dual-melt (VIM+VAR) is normally mandatory. For standard industrial applications, VIM-only or air-melt (EAF+AOD) may be acceptable but will affect pricing.
Specify the required certificate level — EN10204 3.1 (factory inspection) vs. EN10204 3.2 (third-party witness inspection). If you need 3.2, specify your nominated inspection body in advance.
Confirm NDT requirements — do not rely on default UT acceptance criteria. Specify the class: SEP 1923 Class 2b, ASTM A388 Grade, EN10228-3 class, or your own customer spec. UT acceptance criteria vary significantly between standards.
State impact testing requirements explicitly — AISI 330 is tested at room temperature by default. If your application needs Charpy impact values at sub-zero temperatures (common for API 6A PSL 2/3), this must be specified and the forging designed with sufficient test coupon material.
Verify the supplier's melting source traceability — not all "AISI 330" billets are VIM+VAR. Ask for the melt route and ingot heat number before order confirmation. We provide full melt traceability from ingot to finished forging.
Clarify surface condition requirement — as-forged (scale on), shot blasted, turned/peeled to bright bar, or fully machined? Surface condition significantly affects price and lead time. Our default is shot blasted unless otherwise specified.
Do not confuse AISI 330 with AISI 330H or Type 330H — some specifications reference 330H, which is a higher-carbon variant (C: 0.04–0.10%) for improved creep strength. Confirm which variant is needed for your application before ordering.
Request a sample chemical and mechanical test report before bulk order — for new supplier qualification, we recommend qualifying one sample heat with full physical tests before committing to production quantities. We support this qualification process at no charge.

Why Choose Jiangsu Liangyi as Your AISI 330 Forgings Supplier

Capability	Jiangsu Liangyi Details	What This Means for You
ISO 9001:2015 Certified	80,000 m² workshop; 120,000 tons annual capacity; 30 kg–30 ton per piece	Consistent quality management system; scale to handle both prototype and production volume
In-House VIM+VAR Melting	Full dual-melt capability; billet traceability from ingot to finished part	No third-party billet dependence; chemistry guaranteed; supports nuclear & aerospace qualification
Advanced Forging Equipment	2000T–6300T hydraulic presses; 1T–9T hammers; 1M–5M ring rollers; in-house CNC machining	One supplier, one process, zero critical outsourcing — simplifies QC and reduces risk
25+ Years Nickel Alloy Expertise	Specialized in high-nickel alloy forging since 1999 — including UNS N06625, N06601, N08810, N10276, N08330, N04400 and equivalent grades (commonly known in the industry as Inconel®, Incoloy®, Hastelloy® and Monel® alloys)	Alloy-specific forging parameters; fewer rejects; more reliable mechanical properties
Full Certification Support	EN10204 3.1 standard; 3.2 with qualified third-party inspection body (client-nominated); all major international standards	Passes any customer or end-user inspection requirement globally
Competitive Price & Delivery	Direct factory pricing; 98%+ on-time delivery; standard lead time quoted per order	No middleman markup; reliable supply schedule for your project planning
Global Export Track Record	50+ countries; project references available on our Reference page	Proven logistics for international shipment, customs documentation, export compliance

Related Nickel Alloy Forged Materials

Jiangsu Liangyi makes forgings in the full range of nickel-iron-chromium alloys. If AISI 330 may not be the optimal selection for your application, explore these related materials:

Frequently Asked Questions about AISI 330 (UNS N08330) Forgings

What is AISI 330 alloy used for?

AISI 330 (UNS N08330) is used for high-temperature industrial applications needing carburization resistance, oxidation resistance and chloride stress corrosion cracking (SCC) immunity. Key applications:

Furnace fixtures, fans, radiant tubes, salt pots and carburizing furnace internals
Oil and gas: downhole tools, ESP shafts, wellhead valve bodies, casing heads (API 6A)
Petrochemical: heat exchanger shells, tube sheets, catalytic reactor nozzles
Valve bodies, stems, discs for high-temperature service
Nuclear power: coolant pump components, structural parts

Maximum continuous service temperature is1093°C (2000°F) in oxidizing atmospheres; 982°C (1800°F) in carburizing atmospheres.

What is the UNS number for AISI 330? What are all the equivalent designations?

The UNS number for AISI 330 is N08330. Complete equivalent designation table:

UNS N08330 — Unified Numbering System (USA, primary)
RA330® — Trade name by Rolled Alloys Inc.
Alloy 330 — Generic industry name
JIS SUH330 — Japanese Industrial Standard equivalent
W-Nr. 1.4886 — European material number (closest equivalent, composition may vary slightly)
AISI 330 — American Iron and Steel Institute designation (historical)

What is the difference between AISI 330 and 310S stainless steel?

Four main technical differences:

Nickel content: AISI 330 = 34–37% Ni; 310S = 19–22% Ni. The extra nickel dramatically improves chloride SCC resistance and carburization resistance.
Silicon content: AISI 330 requires minimum 0.75% Si; 310S has no silicon minimum. Silicon is the primary carburization barrier in AISI 330 — 310S lacks this defence mechanism.
Sigma phase embrittlement: AISI 330 is significantly more resistant to sigma phase formation in the 550–900°C range due to its higher nickel content stabilizing the austenite matrix.
Cost: AISI 330 typically costs 30–50% more than 310S due to higher nickel content. This premium is justified for carburizing and SCC-risk applications but not for simple oxidation-only service.

What is the maximum service temperature of AISI 330?

Oxidizing atmosphere (air, O₂-rich): Continuous service is up to 1093°C (2000°F)
Carburizing atmosphere (CO/CH₄ rich): Continuous service is up to 982°C (1800°F)
Nitriding atmospheres: Consult your application engineer — nitrogen absorption can cause embrittlement above 900°C in some environments

For structural (load-bearing) applications, the effective design temperature is significantly lower — use the high-temperature tensile or creep data as the basis for design, not the maximum service temperature.

How does AISI 330 resist carburization? What is the mechanism?

AISI 330 resists carburization through two complementary mechanisms:

Mechanism 1 — Thermodynamic (Nickel): High nickel content (34–37%) reduces the thermodynamic activity of carbon in the alloy matrix. Carbon dissolved in a high-Ni austenite has lower chemical potential, reducing the driving force for further carbon ingress from the atmosphere.
Mechanism 2 — Physical barrier (Silicon): The 0.75–1.50% Si in AISI 330 preferentially oxidizes to form an SiO₂-enriched sub-layer beneath the primary Cr₂O₃ scale. This silica layer is impermeable to carbon and acts as a physical barrier blocking carbon diffusion into the metal.

In practice, AISI 330 shows carburization resistance approximately 3–5× better than 310S in identical carburizing atmospheres at 980°C. 310S lacks both the high-Ni matrix and has no mandatory silicon minimum, leaving it with only the Cr₂O₃ scale as a (much less effective) carburization barrier.

What physical properties and density does AISI 330 have?

Main physical properties of AISI 330 (UNS N08330):

Density: 8.03 g/cm³ (0.290 lb/in³)
Melting range: 1355–1400°C (2475–2550°F)
Thermal conductivity: 11.3 W/m·K at 100°C; 18.7 W/m·K at 600°C
Mean thermal expansion (20–600°C): 15.3 µm/m·°C
Electrical resistivity: 1.02 µΩ·m at 20°C
Young's Modulus: 196 GPa at room temperature
Specific heat: 502 J/kg·K at 20°C
Magnetic behavior: Non-magnetic (µ ≈ 1.02) in annealed condition

What filler metal and procedure should be used for welding AISI 330?

Following are recommended welding consumables for AISI 330:

GTAW/GMAW filler wire (primary): ERNiCrFe-7 / ERNiCrFe-7A — best hot cracking resistance
GTAW/GMAW filler wire (alternative): ER330 — matching composition, lower cost
SMAW covered electrode: AWS A5.11 ENiCrFe-3

Procedure: No preheating is needed.Keep the inter-pass temperature at or below 150°C.Use low to medium heat input; stringer beads are recommended.Post-weld heat treatment is not needed for most uses.Solution annealing at 1038°C brings back the best corrosion resistance for critical applications.

Avoid: ER309L — it has only ~13% Ni and creates a severe galvanic mismatch with AISI 330 base metal at the weld zone.

Can you manufacture custom AISI 330 forgings per customer drawings?

Yes. Jiangsu Liangyi specializes in custom AISI 330 forgings to customer drawings, including:

All product forms: bars, rings, hollow forgings, discs and custom shapes
Weight: 30 kg to 30,000 kg per piece
Full in-house process: VIM+VAR melting → forging → ring rolling → heat treatment → CNC machining
All standard certifications and third-party inspection support
Typical lead time: it is 6–14 weeks depending on weight and shape(confirm with our team)

Send drawings, material specs, quantity and delivery requirements to sales@jnmtforgedparts.com or via our online contact form for a free quote.

Why choose forged AISI 330 over cast or plate?

Forged AISI 330 has clear advantages for pressure-critical and fatigue-critical applications:

30–50% higher fatigue life than equivalent castings due to refined grain matrix and continuous grain flow
Better UT inspectability: Forgings get SEP 1923 Class 2b acceptance; castings typically only Class 3
No porosity or shrinkage defects: Forging mechanically closes all solidification voids from the original ingot
Single-piece integrity: No weld repair risk — important for pressure vessel nozzles, valve bodies and nuclear parts where weld repair is prohibited
Better machinability than castings — lower inclusion content from VIM+VAR melting reduces abrasive tool wear by 15–20%

What certifications does Jiangsu Liangyi hold for AISI 330 forgings?

Certifications and inspection support are provided with every AISI 330 forging order:

Factory quality certification: ISO 9001:2015
Material test certificates: EN10204 3.1 (standard) or EN10204 3.2 (with authorized third-party witness)
Third-party inspection: EN10204 3.2 available — client nominates their preferred qualified inspection body
Chemical analysis standard: ASTM E 353
Mechanical testing: ASTM E 8/E 8M (tensile), E 18 (hardness), E 23 (Charpy impact, on request)
AMS standards: AMS 2241, 2248, 2371, 2374, 2806, 2808, 7490
Oil & gas: API 6A (manufactured to standard per customer order requirements; API Monogram license not held)

What is AISI 330H (Type 330H)? How is it different from AISI 330?

AISI 330H (also known as Type 330H or UNS N08332 in some standards) is a higher-carbon version of AISI 330.Its carbon content is usually 0.04–0.10%, while standard AISI 330 has a maximum of 0.08%.The higher carbon improves creep strength and stress rupture life above 760°C, though it slightly reduces maximum corrosion resistance.330H is used when parts must carry loads long-term at very high temperatures, such as furnace rolls and hangers in continuous annealing lines.For most applications needing resistance to carburization and SCC, standard AISI 330 (UNS N08330) works well and is preferred.Always check which grade your specification requires before ordering.

What is sigma phase embrittlement and how does AISI 330 resist it?

Sigma phase is a hard, brittle metal compound (Fe-Cr-Ni) that can form in austenitic stainless steels and nickel alloys.This happens when the material is held at medium temperatures (around 550–900°C) for a long time.When sigma phase forms, the metal becomes less ductile and tougher to withstand impact.It can also break suddenly when cooled quickly from operating temperature (thermal shock).
AISI 330 resists sigma phase better than 310S for two main reasons:
(1) Its higher nickel content (34–37% vs. 19–22% in 310S) keeps the matrix stable and reduces sigma phase formation.
(2) Its lower chromium content (17–20% vs. 24–26% in 310S) also lowers sigma phase tendency, since chromium is the main element that forms it.
For long-term use at 650–900°C, AISI 330 stays much more ductile than 310S or 304H.

Does AISI 330 require any special considerations for machining?

AISI 330 is machinable but is classified as difficult-to-machine due to austenitic work hardening. Key guidance:

Tooling: Coated carbide inserts (TiAlN or AlTiN) required — HSS wears rapidly
Cutting speed: 30–50% lower than 316L stainless as a starting point (~40–60 m/min turning)
Feed rate: Maintain positive, consistent feed — dwell causes work hardening and tool failure
Coolant: Flood coolant essential; sulphurised cutting oil for drilling and tapping
Chip control: Use chip-breaker geometry inserts — AISI 330 forms long, stringy chips

Our VIM+VAR forged AISI 330 shows 15–20% better tool life than standard mill bar stock due to lower inclusion content reducing abrasive wear.

What is the minimum order quantity (MOQ) for AISI 330 forgings?

Jiangsu Liangyi has no fixed minimum order quantity for AISI 330 forgings. We can supply both one sample orders (minimum 30 kg) to large production batches. However, be aware that:

A single forging heat (melt charge) typically yields enough material for multiple pieces — ordering a full heat quantity reduces per-piece cost significantly
For very small quantities (<100 kg total), we may source pre-existing billet stock rather than dedicate a new melt, which can shorten lead time
Lead time differs by order size — contact us with your specific quantity and timeline for an accurate quotation

How do I send an RFQ (Request for Quotation) for AISI 330 forgings?

To get an accurate quotation, please provide the following in your RFQ:

Product form (bar, ring, hollow, disc, custom shape)
Finished dimensions (or rough forging dimensions with machining allowance)
Quantity (pieces or kilograms)
Material specification (AISI 330 / UNS N08330; reference standard e.g. AMS 7490 for rings)
Melt route needed (VIM+VAR, or standard)
Certificate needed (EN10204 3.1 or 3.2; inspection body if 3.2)
NDT requirements (UT class, MT, PT)
Needed delivery date / lead time
Drawings (PDF or DXF) if custom machined shape required

Send to: sales@jnmtforgedparts.com | WhatsApp: +86-13585067993 | Online contact form

Request a Custom AISI 330 Forging Quote

Jiangsu Liangyi provides competitive factory pricing and high-quality AISI 330 (UNS N08330 / RA330® / Alloy 330) forgings for customers around the world.We offer both standard and fully custom parts, Both one sample orders and large volume mass production orders are ok. We deliver customized solutions from design review all the way to certified delivery.

Send your drawings, material specifications, quantity and project details for a free, no-obligation quotation — typically within 24 hours.

Email: sales@jnmtforgedparts.com

Phone/WhatsApp: +86-13585067993

Website: www.jnmtforgedparts.com

Address: Chengchang Industry Park, Jiangyin, Jiangsu 214400, China