Quick Reference — Hastelloy B2 (Alloy B-2 / UNS N10665) Forging Parts by Jiangsu Liangyi
- Alloy designations
- Hastelloy B2 · Alloy B-2 · UNS N10665 · W.Nr. 2.4617
- Alloy system
- Binary Ni-Mo: nickel balance + 26–30% molybdenum
- Primary design purpose
- Maximum resistance to pure reducing acids — HCl (all concentrations, to boiling), H₂SO₄, H₃PO₄, HCOOH
- Hard exclusion
- Oxidizing media — HNO₃, Cl₂, ferric/cupric salts, dissolved O₂ — alloy fails rapidly
- Max service temperature
- 400 °C (750 °F) in corrosive reducing service
- Solution anneal
- 1065 °C min → rapid water quench
- Min yield strength
- 352 MPa (51 KSI)
- Min tensile strength
- 758 MPa (110 KSI)
- Min elongation
- 40%
- Density
- 9.22 g/cm³
- Weight range
- 30 kg – 30,000 kg per piece
- Max ring OD
- 6 m
- Lead time
- 4–6 weeks standard · 2–3 weeks expedited
- Quality certification
- ISO 9001:2015
- Applicable standards
- ASTM B564 · API 6A · ASME VIII · NACE MR0175/ISO 15156 · EN 10204-3.1
- Manufacturer
- Jiangsu Liangyi Co., Ltd — Jiangyin, Jiangsu, China (est. 1997)
Product Overview
Jiangsu Liangyi Co., Limited manufactures Hastelloy B2 (Alloy B-2, UNS N10665) open die forgings and seamless rolled rings from its 80,000 m² facility in Jiangyin, Jiangsu, China. Established in 1997 and ISO 9001:2015 certified, the company operates forging presses from 2,000 to 6,300 tonnes and ring rolling mills producing rings up to 6 m in outer diameter. Annual output exceeds 120,000 tonnes across all alloy grades. Components ship to customers in more than 50 countries, supported by full EN 10204-3.1 documentation and a range of third-party inspection options.
Hastelloy B2 forged round bars — solution-annealed and water-quenched, ready for machining or direct inspection. Jiangsu Liangyi, Jiangyin, China.
Hastelloy B2 is a binary nickel-molybdenum alloy. With 26–30% molybdenum and deliberately minimized chromium (≤1%), it is purpose-built for reducing acid environments where chromium-containing alloys like Hastelloy C276 underperform. The high molybdenum content stabilizes the passive film against dissolution by non-oxidizing acids, giving the alloy its defining capability: resistance to hydrochloric acid at any concentration, including the boiling point. Our UNS N10665 forgings are manufactured and tested to ASTM B564, API 6A, and customer-specific standards.
Where Hastelloy B2 Outperforms Alternative Alloys
- Hydrochloric acid at all concentrations from dilute to 37% fuming, including at the boiling point — no other standard engineering alloy matches this
- Sulfuric acid across the full concentration range in the absence of oxidizing contaminants
- Phosphoric acid, acetic acid, and formic acid at elevated temperatures
- Dry hydrogen chloride gas at temperatures up to 650 °C
- Sour gas service (H₂S + CO₂) per NACE MR0175/ISO 15156 — resists sulfide stress cracking
- Higher yield strength (352 MPa min) than Hastelloy C276 (283 MPa min) — useful where pressure rating or wall thickness reduction is the design driver
Manufacturing Capabilities — Jiangyin, China
Every Hastelloy B2 forging produced at our Jiangyin facility is tracked from ingot to dispatch under a single quality plan. Melting, forging, heat treatment, machining, and NDT are all performed in-house, eliminating subcontractor risk and compressing lead times. Jiangyin's position on the Yangtze River gives direct access to major export ports, with standard sea-freight transit of 18–35 days to most destinations worldwide.
Equipment
- Forging presses: 2,000T, 4,000T, and 6,300T hydraulic open die forging presses; 3T and 5T electro-hydraulic forging hammers
- Ring rolling: 1 m and 5 m radial-axial ring rolling mills; finished ring OD up to 6 m, weight up to 30 t
- Melting: 30t EAF + LF + VOD route for standard grades; VIM, ESR, and VAR furnaces for premium-grade ingots
- Heat treatment: Ten computer-controlled furnaces with calibrated atmosphere and quench capability; solution anneal at 1065 °C + forced water quench as standard for Hastelloy B2
- Machining: CNC turning centres to 3 m swing; horizontal boring mills; grinding to Ra 0.4 µm
- NDT: Phased-array UT, conventional UT, MT, and PT; in-house PMI; OES chemical analysis; universal tensile testing to 1,000 kN
Available Product Forms and Size Range
- Seamless rolled rings: OD 200 mm – 6,000 mm; wall thickness ≥ 50 mm; weight 5 kg – 30,000 kg; rectangular or profiled cross-sections
- Round bars: Diameter 50 mm – 2,000 mm; length up to 6,000 mm
- Discs and blocks: Diameter up to 3,000 mm; thickness as required
- Hollow forgings: Hubs, housings, sleeves, heavy-wall cylinders; OD up to 3,000 mm
- Shafts: Stepped and straight shafts up to 15,000 mm in length
- Custom profiles: Flanged blanks, near-net-shape forgings, complex contoured forgings per customer drawing
Alloy B-2 seamless rolled rings — OD up to 6 m, produced on Jiangsu Liangyi's 5 m radial-axial ring mill, Jiangyin, China.
Industry Applications for UNS N10665 Forged Components
Hastelloy B2 forgings are selected when the design challenge is pure reducing acid corrosion and when alternative alloys fail to achieve acceptable service life. The following applications represent established end-use cases where Jiangsu Liangyi components are currently in service.
Oil & Gas — Sour Service
H₂S and CO₂ co-exist in sour gas fields at partial pressures capable of causing sulfide stress cracking in conventional alloys. Hastelloy B2 qualifies for sour service under NACE MR0175/ISO 15156 and is selected for downhole and wellhead components where both SSC resistance and resistance to co-produced reducing acids are required simultaneously.
- Wellhead: casing heads, tubing heads, casing hangers, tubing hangers (API 6A PSL2/PSL3 requirements)
- Downhole: mud motor splined drive shafts, drilling collar sections, connectors
- Surface: gate valve bodies, choke bodies, adapter flanges for sour service headers
- Subsea: tree bodies, connector hubs, and structural forgings (API 17D)
Valve Manufacturing
Valve manufacturers specify Alloy B-2 forged blanks for ball, gate, globe, and butterfly valves handling concentrated acids or sour streams. The alloy's high yield strength (352 MPa min) allows thinner wall sections compared to softer nickel alloys, important in compact valve designs.
- Ball valve balls, stems, seats, and seat rings for HCl and H₂SO₄ service
- Gate and globe valve bodies and bonnets for chemical plant acid headers
- Butterfly valve shaft and disc forgings for large-bore acid lines
- Control valve trim components — plugs, cages, seats — for corrosive throttling service
Power Generation
In power generation, Hastelloy B2 is used in critical components requiring high strength and corrosion resistance at elevated temperatures. We supply Hastelloy B2 forgings for power generation applications with VIM+ESR+VAR triple-melt ingots, full volumetric and surface NDT, and EN 10204-3.2 third-party witness documentation when required by the customer.
- Reactor coolant pump casings, impellers, and diffuser rings
- Steam generator nozzle forgings and inlet/outlet header sections
- Main steam and feedwater isolation valve bodies (MSV/GV/CV/CRV)
- Gas turbine compressor casing sections exposed to reducing condensates
Chemical Processing
The chemical and petrochemical industry accounts for the largest volume of Hastelloy B2 forged components globally. Hydrochloric acid production, sulfuric acid alkylation units, phosphoric acid wet-process plants, and pharmaceutical active ingredient synthesis all depend on this alloy where stainless steel or titanium cannot meet the corrosion requirement.
- Heat exchanger tube sheets, floating heads, and channel flanges for HCl service
- Centrifugal pump casings, impellers, wear rings, and back-covers
- Reactor vessel nozzles, agitator shafts, and impeller hubs
- Venturi and ultrasonic flow meter bodies in aggressive acid streams
- Vacuum system components — ejector bodies, condensers — in acid recovery
Documented Service Performance
The following cases represent actual supply and service outcomes for Jiangsu Liangyi Hastelloy B2 forgings. Customer names are not disclosed; technical parameters are factual.
Sulfuric Acid Alkylation Unit — Pump Casings
A European refinery running 98% H₂SO₄ at 150 °C replaced 316L stainless pump casings that failed every 8–10 months. Jiangsu Liangyi Hastelloy B2 casings have been in continuous service for over 8 years with no measurable wall loss.
10× improvement in service lifeReactor Coolant Pump — Impellers & Casings
VIM+ESR+VAR triple-melt ingots. 100% volumetric UT + surface MT. EN 10204-3.2 with third-party witness. In service on a major Asian nuclear station's primary coolant loop for more than 15 years with no reported material-related degradation.
15+ years zero failuresSour Gas Field — Casing Head Forgings
H₂S at 15 bar partial pressure, CO₂ at 20 bar. API 6A PSL3 testing requirements. EN 10204-3.2 documentation. Hardness verified ≤ 22 HRC at every quadrant. Five years in subsea service without corrosion-related intervention.
60% reduction in maintenance costAntibiotic Reactor — Agitator Shafts & Nozzles
Acetic and hydrochloric acid at 120 °C. Surface finish Ra ≤ 0.4 µm, electropolished to FDA 21 CFR Part 177 requirements. Full traceability per 21 CFR Part 211. Five years in service: zero contamination incidents, zero unscheduled maintenance.
5 years · zero failuresChemical Composition of Hastelloy B2 (UNS N10665)
The composition limits below are specified in ASTM B564 and AMS 5756. Chromium is deliberately controlled to ≤ 1.0% — the lowest of any commercial nickel alloy. This is intentional: chromium does not passivate in reducing acids and would dilute the molybdenum contribution. The entire corrosion resistance of this alloy is carried by molybdenum.
| Element | Specification Limit (%) | Metallurgical Function |
|---|---|---|
| Nickel (Ni) | Balance (≈ 66–70%) | Ductile base matrix; provides intrinsic resistance to non-oxidizing acids |
| Molybdenum (Mo) | 26.00 – 30.00 | Primary corrosion resistance mechanism — stabilizes passive film in HCl and H₂SO₄; raises pitting potential |
| Iron (Fe) | 2.00 max | Controlled at low levels to avoid degrading reducing acid resistance; improves hot workability marginally |
| Chromium (Cr) | 1.00 max | Deliberately minimized — chromium is not passive in reducing acids and would dilute the Mo contribution |
| Cobalt (Co) | 1.00 max | Residual element from raw materials; controlled to maintain property consistency |
| Manganese (Mn) | 1.00 max | Improves hot ductility during forging; kept low to avoid MnS inclusion formation |
| Silicon (Si) | 0.10 max | Tightly restricted — silicon segregates to grain boundaries and promotes intergranular attack in reducing acid service |
| Phosphorus (P) | 0.040 max | Grain-boundary embrittlement risk; low limit prevents hot cracking during solidification |
| Sulfur (S) | 0.030 max | Controlled to prevent MnS stringers which act as corrosion initiation sites and impair weldability |
| Carbon (C) | 0.02 max | Critical limit — excess carbon precipitates as M₆C carbides at grain boundaries during slow cooling, severely degrading intergranular corrosion resistance |
Physical and Thermophysical Properties
The data below applies to the solution-annealed condition at room temperature unless a temperature is stated. These values are used in heat exchanger thermal design, piping stress analysis, and finite element calculations for pressure-containing forgings.
| Property | Value | Unit | Temperature / Condition |
|---|---|---|---|
| Density | 9.22 | g/cm³ (0.333 lb/in³) | Room temperature |
| Melting range | 1330 – 1380 | °C (2426 – 2516 °F) | Liquidus–solidus interval |
| Thermal conductivity | 11.1 | W/m·K | 23 °C (73 °F) |
| Thermal conductivity | 16.3 | W/m·K | 500 °C (932 °F) |
| Mean CTE | 10.0 | µm/m·°C (5.6 µin/in·°F) | 25 – 100 °C |
| Mean CTE | 11.6 | µm/m·°C | 25 – 500 °C |
| Specific heat capacity (Cₚ) | 373 | J/kg·K (0.089 BTU/lb·°F) | 23 °C (73 °F) |
| Electrical resistivity | 137 | µΩ·cm | Room temperature |
| Modulus of elasticity (E) | 217 | GPa (31.5 × 10⁶ psi) | Room temperature |
| Shear modulus (G) | 83 | GPa (12.0 × 10⁶ psi) | Room temperature |
| Poisson's ratio (ν) | 0.31 | — | Room temperature |
| Magnetic permeability (µ) | < 1.002 | — | Non-magnetic |
Designer notes: Thermal conductivity at 11.1 W/m·K is approximately one-fifth that of carbon steel. Heat exchanger designers must account for this when sizing tube bundles or shell passes. The CTE of 10.0 µm/m·°C is lower than 316L stainless (16.0 µm/m·°C) — thermal expansion mismatch stress at welds to stainless components must be evaluated if the two materials are joined.
Corrosion Resistance Data — Reducing Acid Service
The benchmark for corrosion acceptability in continuous chemical service is a rate below 0.127 mm/year (5 mils per year, mpy). The data below represents laboratory coupon and field data for Hastelloy B2 (UNS N10665) in deaerated solutions.
These corrosion rates apply only to pure, deaerated reducing acid solutions. Ferric ions (Fe³⁺), cupric ions (Cu²⁺), dissolved oxygen, nitric acid, and hypochlorite — even at trace levels — shift the environment from reducing to oxidizing and can raise the corrosion rate by one to three orders of magnitude. Process stream analysis for oxidizing contaminants is a prerequisite for specifying this alloy.
Hydrochloric Acid (HCl)
This is Hastelloy B2's defining strength. The isocorrosion line at 0.1 mm/year encompasses the full HCl concentration range at all temperatures including the boiling point — a performance envelope no other standard engineering alloy matches.
| HCl Concentration (wt%) | Temperature | Corrosion Rate (mpy) | Assessment |
|---|---|---|---|
| 5% | Boiling (~101 °C) | < 1 | Excellent |
| 10% | Boiling (~102 °C) | < 2 | Excellent |
| 20% | Boiling (~108 °C) | < 5 | Excellent |
| 30% | 65 °C (149 °F) | < 3 | Excellent |
| 37% (concentrated) | Room temperature | < 1 | Excellent |
| 37% (concentrated) | 50 °C (122 °F) | < 10 | Good |
| Any concentration | Any — with Fe³⁺ present | 100 – 1,000+ | Unacceptable |
Sulfuric Acid (H₂SO₄)
| H₂SO₄ Concentration (wt%) | Temperature | Corrosion Rate (mpy) | Assessment |
|---|---|---|---|
| 10% | Boiling (~102 °C) | < 5 | Excellent |
| 30% | Boiling (~115 °C) | < 10 | Good |
| 60% | Boiling (~140 °C) | < 20 | Good |
| 80% | Boiling (~165 °C) | < 15 | Good |
| 96% (oleum range) | Room temperature | < 5 | Excellent |
| Any concentration | Any — with oxidizing impurities | Rapid attack | Unacceptable |
Other Corrosive Media — Summary
| Medium | Conditions | Assessment | Design Notes |
|---|---|---|---|
| Phosphoric acid (H₃PO₄), pure | All concentrations, to boiling | Excellent | Verify absence of HF if wet-process acid |
| Acetic acid (CH₃COOH) | All concentrations, to boiling | Excellent | Superior to titanium in boiling glacial acetic acid |
| Formic acid (HCOOH) | All concentrations, to boiling | Excellent | One of few alloys to perform in strong formic |
| HF, anhydrous | Room temperature, dry | Good | Restrict to dry conditions; moist HF is more aggressive |
| HCl gas, dry | Up to 650 °C (1,202 °F) | Excellent | Unique advantage over most nickel alloys |
| Sour gas (H₂S + CO₂) | Per NACE MR0175 Zone III | Excellent | Hardness must be verified ≤ 35 HRC per NACE |
| Nitric acid (HNO₃) | Any concentration | Not suitable | Oxidizing — use Alloy C276 or C22 |
| Chromic acid (H₂CrO₄) | Any concentration | Not suitable | Strongly oxidizing — causes rapid corrosion |
| Wet chlorine / hypochlorite | Any | Not suitable | Oxidizing halide — severe pitting risk |
| Seawater | Ambient, flowing or stagnant | Limited | Risk of crevice corrosion in stagnant zones; use C276 or 625 |
| Mixed reducing + trace oxidizing | Any | Avoid B2 | Even trace Fe³⁺ or O₂ can cause rapid attack — specify C276 |
Hastelloy B2 vs. Hastelloy B3 — The Critical Distinction
The question of B2 versus B3 comes up on virtually every specification for nickel-molybdenum alloy in reducing acid service. Understanding the metallurgical distinction prevents specification errors that result in premature corrosion after welding or thermal cycling.
Why Hastelloy B3 Was Developed
When Hastelloy B2 is slow-cooled through the 400–700 °C range — during post-weld cooling, post-weld stress relief, or service excursions — the nickel and molybdenum atoms rearrange into ordered intermetallic structures of the Ni₄Mo type. This ordering reaction reduces ductility and depletes the grain boundaries of molybdenum, creating preferred paths for intergranular corrosion. Field failures of B2 welded fabrications in the 1990s were attributed to this mechanism.
Hastelloy B3 (UNS N10675) uses a modified composition — 1–3% Cr, lower Fe (≤1.5%), adjusted Co and Mn — to suppress ordering reactions, making B3 significantly more tolerant of welding thermal cycles. Corrosion resistance to reducing acids is essentially equivalent between the two alloys.
For forged components supplied in the fully solution-annealed and water-quenched condition that will not subsequently be welded in the field, Hastelloy B2 is a sound and cost-effective specification. The sensitization risk applies only when the alloy is reheated into the 400–700 °C range after fabrication. For welded vessels, plate fabrications, or assemblies that will see field welding without a subsequent full solution anneal, specify Hastelloy B3.
| Parameter | Hastelloy B2 (UNS N10665) | Hastelloy B3 (UNS N10675) |
|---|---|---|
| UNS designation | N10665 | N10675 |
| European W.Nr. | 2.4617 | 2.4600 |
| Mo content | 26–30% | 28.5–31.5% |
| Cr content | 1.0% max | 1.0–3.0% |
| Fe content | 2.0% max | 1.5% max |
| Ni₄Mo ordering susceptibility | High — slow cooling through 400–700 °C causes ordering | Low — composition suppresses ordering kinetics |
| HAZ sensitization risk after welding | Significant — post-weld solution anneal + WQ strongly recommended | Substantially reduced — more tolerant of as-welded condition |
| Min yield strength (solution annealed) | 352 MPa (51 KSI) | 310 MPa (45 KSI) |
| Min tensile strength | 758 MPa (110 KSI) | 690 MPa (100 KSI) |
| HCl corrosion resistance | Excellent | Excellent (equivalent) |
| H₂SO₄ corrosion resistance | Excellent | Excellent (equivalent) |
| Availability as forgings | Wide global availability; typically stocked at mills | Moderate — may require mill order, longer lead time |
| Specify when: | Forged components, solution-annealed delivery, no field welding | Welded fabrications, field-welded assemblies, thermal cycling in sensitization range |
Alloy Selection Guide — B2 vs. C276, C22, 625, 316L
Material selection for corrosion-resistant forged components should begin with the process environment, not the alloy name. The matrix below covers the five most common alternatives across the performance dimensions that drive industrial selection decisions.
| Criteria | B2 (N10665) | B3 (N10675) | C276 (N10276) | C22 (N06022) | 625 (N06625) | 316L (S31603) |
|---|---|---|---|---|---|---|
| Key alloying | Ni-28Mo | Ni-29Mo-2Cr | Ni-16Mo-15Cr | Ni-13Mo-22Cr | Ni-9Mo-21Cr-3.5Nb | Fe-18Cr-10Ni-2Mo |
| Reducing acids (HCl, H₂SO₄) | Best-in-class | Equivalent to B2 | Very Good | Good | Good | Poor |
| Oxidizing acids (HNO₃) | Not Suitable | Not Suitable | Very Good | Excellent | Very Good | Moderate |
| Mixed / contaminated acid | Avoid | Avoid | Best Choice | Excellent | Very Good | Limited |
| Chloride pitting / crevice | Good | Good | Excellent | Excellent | Very Good | Moderate |
| Sour service (NACE MR0175) | Excellent | Excellent | Excellent | Excellent | Very Good | Limited |
| Min yield strength | 352 MPa | 310 MPa | 283 MPa | 310 MPa | 414 MPa | 170 MPa |
| Max corrosive service temp. | ~400 °C | ~400 °C | ~650 °C | ~650 °C | ~980 °C | ~300 °C |
| Weldability | Requires PWHT | Better | Good | Good | Excellent | Excellent |
| Relative cost | High | High | High | Very high | Very high | Low |
| Specify for: | Pure HCl or H₂SO₄, no oxidizing contamination | Same as B2 + welded fabrications | Mixed, oxidizing, or unknown streams; chlorides | Strongly oxidizing or mixed media | High-temp; seawater; fatigue-critical | Mild corrosion; cost-driven |
Melting Routes and Heat Treatment
The melting route determines inclusion cleanliness, segregation level, and ultrasonic inspectability. Jiangsu Liangyi offers two qualified routes for UNS N10665:
- VIM + VAR (double melt) — standard industrial grade: Vacuum induction melting removes dissolved gases and volatile tramp elements; VAR remelting refines ingot structure, reduces segregation, and improves UT transparency. Suitable for chemical, oil and gas, and most power generation applications.
- VIM + ESR + VAR (triple melt) — premium grade: ESR adds a second refining step that further reduces inclusion content and macro-segregation. Specified for the most demanding applications — high-cycle fatigue, power generation, and customer specifications mandating triple-melt ingot. Higher cost and longer lead time; specify only when required.
Standard heat treatment: Solution anneal at a minimum of 1065 °C (1950 °F), holding for sufficient time to ensure full homogenization through section thickness, followed by rapid water quench. The quench rate is critical — slow air cooling through the 700–400 °C range risks Ni₄Mo ordering. For forgings with section thickness above 150 mm, forced-water immersion quench is used, not spray quench, to ensure adequate cooling rate through the full section.
Production Sequence — From Ingot to Dispatch
- Ingot production VIM+VAR or VIM+ESR+VAR per customer specification. Ingot chemistry verified by OES before release to forging.
- Billet heating and hot working Ingots heated to the forging temperature range and worked on 2,000T–6,300T hydraulic presses (open die forgings) or on the 5 m radial-axial ring mill (rings to 6 m OD). Total reduction ratio controlled to achieve the specified grain size requirement.
- Solution anneal + water quench Minimum 1065 °C, hold time proportional to section thickness, followed by forced water immersion quench. Furnace calibration records retained as part of the heat treatment certificate.
- CNC machining (when specified) Rough-machined, semi-finished, or fully finished per customer drawing. Hastelloy B2 is moderately difficult to machine; carbide inserts with positive rake geometry and flooded coolant manage work hardening.
- Non-destructive testing 100% volumetric UT per ASTM A388; surface MT per ASTM E709; surface PT per ASTM E165. Acceptance criteria per applicable code.
- Mechanical and chemical testing Tensile, yield, elongation, and hardness from each heat and heat treatment lot per ASTM B564. Hardness mapping for sour service components per NACE MR0175.
- Documentation and dispatch EN 10204-3.1 certificate issued. Full documentation package assembled. Components packaged in VCI film and shipped from Jiangyin port within the agreed schedule.
Mechanical Properties (UNS N10665 Forgings)
All Hastelloy B2 forged parts are supplied in the solution-annealed condition. The values below are guaranteed minimums at room temperature per ASTM B564. Jiangsu Liangyi reports actual test values — not just pass/fail — on the EN 10204-3.1 certificate.
| Property | SI minimum | US Customary minimum | Test method |
|---|---|---|---|
| Yield Strength (0.2% proof) | Yield Strength 352 MPa | 51 KSI | ASTM E8 / EN ISO 6892-1 |
| Ultimate Tensile Strength | 758 MPa | 110 KSI | ASTM E8 / EN ISO 6892-1 |
| Elongation (50 mm gauge) | 40% minimum | ASTM E8 | |
| Reduction of area | Typically 55–65% (not specified in ASTM B564) | ASTM E8 | |
| Hardness | Typically 200–250 HB; ≤ 35 HRC for NACE MR0175 sour service | ASTM E10 / ASTM E18 | |
Welding Guide for Hastelloy B2 Fabricators
Hastelloy B2 can be successfully welded, but it requires more procedural discipline than Hastelloy C276 or Alloy 625. All welding procedures should be qualified per ASME Section IX or EN ISO 15614-1 before production welding.
Slow cooling through 400–700 °C causes Ni₄Mo ordering that depletes grain boundaries of molybdenum. The HAZ then corrodes preferentially in the service environment the alloy was chosen to resist. This failure mode is irreversible without a full re-solution anneal. Thermal stress relief in the 400–700 °C range is absolutely prohibited.
Recommended Welding Consumables
| Process | Recommended consumable | AWS classification | Notes |
|---|---|---|---|
| GTAW (TIG) | Hastelloy W / B-3 filler wire | AWS A5.14 ERNiMo-3 | Preferred for root passes and all corrosion-critical welds |
| GMAW (MIG) | Hastelloy W wire | AWS A5.14 ERNiMo-3 | Ar or Ar+He only; spray transfer preferred |
| SMAW (stick) | Hastelloy W coated electrode | AWS A5.11 ENiMo-3 | Remove slag fully between each pass |
| SAW | Not recommended | — | Heat input too high; HAZ sensitization unavoidable |
| Dissimilar to carbon steel | Alloy 625 filler | AWS A5.14 ERNiCrMo-3 | Buffer layer; verify dilution effect on corrosion performance |
Procedure Requirements
- Joint preparation: Machine or grind joint faces — flame cutting leaves a thermally damaged edge that must be removed. Degrease with acetone. Remove all iron contamination — even transfer from mild steel tooling degrades weld corrosion resistance.
- Preheat: None — preheat extends time in the sensitization range and is detrimental.
- Interpass temperature: ≤ 150 °C (302 °F) maximum. Monitor with contact thermometer between each pass. Allow natural air cooling — no forced cooling on heavy sections.
- Heat input: ≤ 1.5 kJ/mm. Stringer beads only — weave beads are not permitted.
- Shielding gas: 99.99% Ar or Ar + 25–50% He. Back-purge all root passes with 99.99% Ar until weld is fully cooled below 300 °C.
- Post-weld heat treatment: Full solution anneal at ≥ 1065 °C + rapid water quench after all welding is complete. The only PWHT that restores full corrosion resistance.
- Prohibited PWHT: Stress relief at 400–700 °C is absolutely prohibited — it causes sensitization. If code requires stress relief and re-solution anneal is impractical, specify Hastelloy B3 instead.
- Post-weld cleaning: Wire-brush with stainless brush (never carbon steel). Pickle weld and HAZ with HNO₃/HF pickling paste; rinse thoroughly; passivate per specification.
Weld Inspection
- VT: 100% visual examination — all welds, all passes
- PT: 100% liquid penetrant per ASTM E165 on all finished welds
- RT or UT: Volumetric examination of butt welds per applicable code
- ASTM G28 Method A sensitization test: Required for ASME pressure equipment welds in corrosive service — corrosion rate ≤ 1.0 mm/year in boiling H₂SO₄/Fe₂(SO₄)₃ is the acceptance criterion
Quality Assurance and Certifications
Every Hastelloy B2 forging produced at Jiangyin operates under a documented quality plan that specifies inspection hold points from ingot receipt through final dimensional inspection. The quality system is certified to ISO 9001:2015, audited annually by an accredited third-party certification body.
Quality Certification
- ISO 9001:2015 — Quality Management System certification covering the full production scope: melting, forging, heat treatment, machining, NDT, and testing. Certificate available on request.
Standards We Produce and Test To (Customer-Specified)
Jiangsu Liangyi does not hold product-specific body certifications such as an API 6A licence, ASME N-stamp, or CE Notified Body approval. However, we routinely manufacture and test Hastelloy B2 forgings to these standards when specified by customers:
- ASTM B564 — Nickel alloy forgings; primary product standard for all Hastelloy B2 supply
- API 6A (PSL1 / PSL2 / PSL3) — Wellhead and Christmas tree equipment material and testing requirements; hardness, impact, and documentation requirements met per the applicable PSL
- NACE MR0175 / ISO 15156 — Material requirements for sour service; hardness control and documentation per Part 3 applied as standard for all sour-service inquiries
- ASME VIII (Div.1 and Div.2) — Pressure vessel material requirements; ASME SB-564 material specification met; U-stamp fabrication is the responsibility of the vessel manufacturer
- AMS 5756 — Aerospace material specification for Ni-Mo alloy forgings; can be accommodated with customer review of our qualification data
- EN 10204-3.1 and 3.2 — Mill certification as standard (3.1); third-party witness documentation (3.2) available through customer-nominated independent inspection body
For applications requiring ASME Section III (nuclear N-stamp) or CE Marking (Notified Body conformity assessment): These certifications require body approvals that are outside our current scope. Contact our engineering team at the inquiry stage — we can advise on the documentation and testing we can supply to support your conformity assessment process.
Standard Documentation Package
- EN 10204-3.1 Inspection Certificate — heat analysis, product analysis, mechanical test results, heat treatment parameters, and NDT results signed by Jiangsu Liangyi's authorised inspector
- EN 10204-3.2 Certificate — with third-party witness by a customer-nominated inspection body (SGS, Bureau Veritas, TÜV, Lloyd's Register, etc.); specify at time of order to allow scheduling
- Heat treatment record — furnace ID, calibration reference, load temperature, soak time, and quench confirmation
- NDT reports — individual UT, MT, and PT records with scanning maps, acceptance criteria, and inspector qualification details
- Dimensional inspection report — all critical dimensions per drawing, signed and stamped
Documentation is archived for a minimum of 15 years post-delivery. Surplus test material is retained for at least three months post-acceptance.
Applicable Testing and Inspection Standards
- ASTM B564 — Nickel alloy forgings (primary product standard)
- ASTM B335 — Nickel-molybdenum alloy rod
- AMS 5756 — Aerospace nickel alloy forgings
- ASME SB-564 — BPVC version of ASTM B564
- ASTM A388 — Ultrasonic examination of steel forgings
- ASTM E165 — Liquid penetrant examination
- ASTM E709 — Magnetic particle examination
- ASTM E112 — Average grain size determination
- ASTM G28 — Corrosion testing / sensitization check
- EN ISO 6892-1:2020 — Tensile testing at ambient temperature
- EN 10204 — Types of inspection documents
Why Customers Source from Jiangsu Liangyi
Melting, forging, heat treatment, machining, and NDT all performed at the Jiangyin site. No subcontractors in the critical path. Every operation documented in a single traceable record set.
Over 25 years of production experience with Ni-Mo, Ni-Cr-Mo, and other high-alloy grades. Process parameters are refined from real production history, not generic data sheets.
120,000 tonnes per year distributes fixed costs across high volumes, making small custom orders economically viable without the premium typical of specialty forges.
Seamless rolled rings up to 6 m in outer diameter as single-piece forgings — no welds, no seams, no preferential corrosion paths. A design advantage welded-and-rolled alternatives cannot match.
We routinely produce to API 6A PSL2/PSL3, ASME VIII, and NACE MR0175 Zone III testing and documentation requirements. Our engineering team will review your specification before you commit to an order.
Factory within 30 km of Jiangyin port. Typical transit: 18–25 days to the Middle East, 25–35 days to Europe, 20–30 days to North American East Coast.
How to Order — Specification Checklist
A complete specification at inquiry stage eliminates revision cycles and delivers an accurate quotation first time. The following checklist covers everything our engineering team needs to produce a firm offer.
| # | Required information | Typical specification example |
|---|---|---|
| 01 | Material designation | Hastelloy B2, UNS N10665, ASTM B564 |
| 02 | Product form | Seamless rolled ring / open die forging / round bar / disc |
| 03 | Dimensions (with drawing preferred) | Ring: OD 1,200 × ID 900 × H 250 mm; Bar: Ø 400 × 1,500 mm L |
| 04 | Dimensional condition and tolerances | As-forged (+10 mm all faces) / rough-machined (+3 mm) / finish-machined per DXF drawing |
| 05 | Quantity and unit weight | 10 pieces, approximately 280 kg each |
| 06 | Melting route | VIM+VAR (standard) or VIM+ESR+VAR (premium) |
| 07 | Heat treatment | Solution annealed 1065 °C min + rapid water quench per ASTM B564 |
| 08 | Mechanical property requirements | Per ASTM B564 minimum; or list specific values if tighter requirements apply |
| 09 | NDT requirements | 100% UT per ASTM A388, Class C; 100% PT per ASTM E165 |
| 10 | Certification level | EN 10204-3.1 (standard) or EN 10204-3.2 with TÜV witness |
| 11 | Applicable industry code | ASME VIII / API 6A PSL2 / NACE MR0175 / customer standard |
| 12 | Special requirements | Surface finish Ra ≤ 1.6 µm; hardness survey per NACE; ASTM G28A corrosion test; 100% PMI |
| 13 | Required delivery | Ex-works Jiangyin within 6 weeks / CIF Rotterdam within 10 weeks |
| 14 | Incoterms and port | FOB Shanghai / CIF Hamburg / DAP Rotterdam |
Packaging and Freight
- Components up to 500 kg: VCI polyethylene film wrap, packed in export-grade wooden cases with moisture-absorbing desiccant. Suitable for groupage container (LCL) shipment.
- Components 500 kg – 5,000 kg: VCI-wrapped and secured to heavy-duty timber pallets with steel strapping. Loaded in standard 20ft or 40ft high-cube containers with loading plan.
- Components above 5,000 kg: Open-top or flat-rack container, or breakbulk cargo. Lifting trunnions engineered into packaging frame. Stowage plan issued with shipping documents.
- Marking: Each piece marked with material grade (UNS N10665), heat number, PO number, piece weight, and Jiangsu Liangyi part number. Compliant with EN 10204 traceability requirements.
Frequently Asked Questions
Hastelloy B2 (UNS N10665, W.Nr. 2.4617) is a binary nickel-molybdenum alloy containing 26–30% molybdenum with a nickel balance and deliberately minimized chromium (≤1%). It is engineered specifically for resistance to pure reducing environments — hydrochloric acid at all concentrations to boiling, sulfuric acid, phosphoric acid, and acetic acid. Chromium is kept low because it does not passivate in reducing acids and would dilute the molybdenum contribution. The alloy is not suitable for oxidizing media. Covered by ASTM B564 for forgings.
Hastelloy B3 (UNS N10675) was developed to solve the thermal instability of B2. When B2 is slow-cooled through 400–700 °C — during welding post-weld cooling or stress relief attempts — Ni₄Mo intermetallic phases form at grain boundaries, depleting molybdenum and creating preferential corrosion paths in the HAZ. B3's modified composition suppresses this ordering reaction. Corrosion resistance to HCl and H₂SO₄ is equivalent. For solution-annealed forgings that will not be welded, B2 is appropriate. For welded fabrications or assemblies subject to field welding without subsequent re-solution anneal, specify B3.
B2 (Ni-28Mo, ≤1% Cr) is the superior choice for pure reducing acids — concentrated HCl, H₂SO₄, H₃PO₄, and HCOOH in the absence of oxidizing contamination. C276 (Ni-16Mo-15Cr) carries sufficient chromium to maintain passivity in both reducing and oxidizing environments, including mixed acids, chloride-containing solutions, and seawater. If your process is strictly pure reducing acid with no oxidizing contaminants, B2 will outperform C276. If there is any uncertainty about oxidizing contamination, or if the medium is mixed or periodically flushed with air or water, C276 is the safer specification.
No. Hastelloy B2 must not be used in oxidizing media. The alloy has no chromium passive film mechanism. Even trace concentrations of ferric chloride, cupric sulfate, dissolved oxygen above 100 ppb, or nitric acid can shift the electrode potential above the critical pitting potential, leading to rapid uniform or pitting corrosion. For oxidizing or mixed environments, specify Hastelloy C276, Hastelloy C22, or another chromium-bearing nickel alloy.
Approximately 400 °C (750 °F) in reducing corrosive service. Above 400 °C the alloy enters the sensitization range (400–700 °C) where Ni₄Mo ordering begins if the temperature is sustained — this degrades corrosion resistance. For reducing acid service above 400 °C, consult with a corrosion metallurgist; Alloy 625 or another thermally stable alloy is typically specified.
Per ASTM B564, solution-annealed condition at room temperature: Yield Strength (0.2% proof) min 352 MPa (51 KSI); Ultimate Tensile Strength min 758 MPa (110 KSI); Elongation min 40% (50 mm gauge). Typical hardness 200–250 HB. For sour service per NACE MR0175, hardness is additionally controlled to ≤ 35 HRC and verified by a full hardness survey map.
Standard lead time is 4–6 weeks from order confirmation and drawing approval — this covers melting, forging, solution anneal, NDT, mechanical testing, and document preparation. Expedited production of 2–3 weeks is available for standard product forms subject to ingot availability. Lead time for VIM+ESR+VAR triple-melt premium-grade forgings is typically 8–12 weeks due to the additional remelting step. Contact our sales team with a full technical specification for a confirmed schedule.
Yes. We supply Hastelloy B2 forgings in as-forged, rough-machined (+3 mm stock), semi-finished, or fully finish-machined condition per customer drawing. Surface finish capability: Ra 0.4 µm for pharmaceutical contact surfaces, Ra 1.6 µm for standard mechanical faces. All finish-machined dimensions are reported in a dimensional inspection report supplied with the EN 10204-3.1 certificate.
Jiangsu Liangyi holds ISO 9001:2015 Quality Management System certification. We do not currently hold API 6A licence, ASME N-stamp, or CE Notified Body approval. However, we routinely manufacture and test Hastelloy B2 forgings to these standards when specified by customers: ASTM B564, API 6A (PSL1/2/3) material and testing requirements, NACE MR0175/ISO 15156 sour service material requirements, and ASME VIII material requirements. EN 10204-3.1 mill certificates are issued as standard. EN 10204-3.2 documentation with a customer-nominated third-party inspection body (SGS, Bureau Veritas, TÜV, Lloyd's Register, etc.) is available on request — specify at inquiry stage to allow scheduling.
Request a Quotation for Hastelloy B2 Forging Parts
Send us your drawing, specification, quantity, and required delivery date. Our engineering team will review the requirement and return a firm quotation — typically within 24 hours for standard inquiries and 48 hours for complex or code-critical specifications.