A complete technical reference covering chemical composition, corrosion data, mechanical properties, welding guidelines, and forging applications for UNS N08031 — the alloy engineers specify when 316L, 904L, and 254SMO are not enough.
1.4562 — also designated X1NiCrMoCu32-28-7 and registered under UNS N08031 — is a premium super austenitic stainless steel designed specifically for industrial environments where conventional grades such as 316L, duplex 2205, 904L, or 254SMO reach the limits of their corrosion resistance.
The term super austenitic describes a class of high-alloy austenitic stainless steels with combined chromium, nickel, molybdenum, and nitrogen content far exceeding the 300 series. Within this class, 1.4562 stands out for two defining features:
Together with 26–28% chromium and 30–32% nickel, these additions produce a Pitting Resistance Equivalent Number (PREN) of approximately 48–52, placing 1.4562 above every common austenitic and duplex stainless steel and within striking distance of Hastelloy® C-276 — at roughly one-third of its cost.
With carbon content limited to ≤ 0.015 wt%, 1.4562 avoids sensitisation (chromium carbide grain-boundary precipitation) in the as-welded condition, eliminating post-weld heat treatment for most pressure equipment applications. This delivers significant fabrication time and cost savings versus nickel-based alloys.
At Jiangsu Liangyi, we supply custom 1.4562 forging parts — open-die bars, seamless rolled rings, hollow forgings, and CNC-machined components — to customers across more than 50 countries. This guide compiles our manufacturing experience with published EN and ASTM material data to give engineers, procurement teams, and fabricators a single authoritative reference.
1.4562 is the EN Werkstoffnummer assigned under EN 10088-3. Depending on which national or international standards system your project documents follow, the same alloy may appear under several different names. Always specify multiple designations in procurement documents to prevent material substitution errors.
| Standards System | Designation | Primary Application / Product Form |
|---|---|---|
| EN (European) | 1.4562 / X1NiCrMoCu32-28-7 | Bars, semi-finished products, forgings (EN 10088-3) |
| UNS (USA) | N08031 | Cross-reference for all ASTM product forms |
| ASTM / ASME | B462 / SB-462 | Forgings & flanges — primary forged-product reference |
| ASTM / ASME | B625 / SB-625 | Plate, sheet, strip |
| ASTM / ASME | B472 / SB-472 | Bar & rod |
| ISO | ISO 15510: X1NiCrMoCu32-28-7 | Chemical composition standard |
| Trade Names | Nicrofer® 3127 hMo · Cronifer® 3127 LC | Mill brand names — always verify chemistry against EN/UNS |
| NACE / API | NACE MR0175 / ISO 15156-3 | Qualified for H₂S sour service (hardness ≤ 22 HRC) |
| Legacy French (NF) | Z1NCDCU32-28 | Superseded by EN 10088-3 in current practice |
Always specify both the EN designation (1.4562 / X1NiCrMoCu32-28-7) and UNS N08031 on every RFQ, purchase order, and mill test certificate. This prevents substitution with lower-grade alloys that share similar-sounding but chemically different designations — a real-world source of field corrosion failures.
Understanding why each element is present is essential for making correct substitution decisions and for interpreting the corrosion data in Section 5. Nominal ranges below are per EN 10088-3.
Most stainless steels contain no intentional copper. In 1.4562, the 1.0–1.4% Cu addition raises the hydrogen overpotential on the alloy surface, which slows the cathodic reaction rate and therefore suppresses active corrosion dissolution in phosphoric and dilute sulfuric acid. Without copper, the corrosion rate in 55–85% H₃PO₄ would be 3–5 times higher, making the alloy unsuitable for fertiliser plant service.
The Pitting Resistance Equivalent Number is the industry-standard formula for ranking localised corrosion resistance:
Any grade with PREN > 40 qualifies as super austenitic. At ~48–52, 1.4562 sits well above 254SMO (~43) and comfortably handles environments that regularly pit or crevice-attack the lower-PREN grades.
All guaranteed values below apply to solution-annealed material per EN 10088-3. Every forging shipped by Jiangsu Liangyi is certified to these minima on the EN 10204 3.1 / 3.2 mill test certificate.
| Property | Guaranteed Value | Test Condition |
|---|---|---|
| Yield Strength (Re) | ≥ 220 MPa | Room temperature, longitudinal |
| Tensile Strength (Rm) | 500 – 700 MPa | Room temperature |
| Elongation (A) | ≥ 40% | Gauge length 5d |
| Hardness | ≤ 230 HB | Brinell, ASTM E10 |
| Impact Energy — Longitudinal (KV) | ≥ 100 J | Charpy V-notch, +20°C |
| Impact Energy — Transverse (KV) | ≥ 60 J | Charpy V-notch, +20°C |
| Impact Energy — Cryogenic (KV) | ≥ 60 J | Charpy V-notch, −196°C |
| Property | Value | Condition / Note |
|---|---|---|
| Density | 8.05 g/cm³ | 20°C, solution annealed |
| Melting Range | 1,330 – 1,380°C | Solidus to liquidus |
| Elastic Modulus (E) | 195 GPa | 20°C; ~175 GPa at 200°C |
| Thermal Conductivity | 12 W/(m·K) | 20°C; rises to ~16 W/(m·K) at 400°C |
| Thermal Expansion | 15.5 × 10⁻⁶ K⁻¹ | 20–100°C range |
| Specific Heat (cp) | 500 J/(kg·K) | 20°C |
| Magnetic Permeability (µr) | ≤ 1.005 | Fully non-magnetic in all conditions |
Maintained transverse impact energy of ≥ 60 J at −196°C makes 1.4562 suitable for LNG and liquid-oxygen applications without a separate cryogenic grade. Duplex stainless steels lose toughness sharply below −50°C — 1.4562 does not, due to its fully austenitic microstructure.
Magnetic permeability µr ≤ 1.005 qualifies 1.4562 for flow measurement bodies, instrumentation housings, and any application where magnetic interference must be eliminated — an advantage over all ferritic and martensitic alternatives.
Generic claims of "excellent corrosion resistance" are meaningless without numbers. The data below gives process engineers concrete figures for material-selection screening and service-life estimation. All values reflect solution-annealed wrought or forged material tested under laboratory immersion conditions.
CPT and CCT are the lowest temperatures at which stable pitting or crevice attack initiates under ASTM G48 standardised test conditions. Higher values mean better resistance.
| Grade | CPT — ASTM G48 Method C (6% FeCl₃) | CCT — ASTM G48 Method D | PREN |
|---|---|---|---|
| 1.4562 (N08031) | > 85°C BEST | > 60°C BEST | ~48–52 |
| 254SMO (1.4547) | ~75°C | ~45°C | ~43 |
| 904L (1.4539) | ~40°C | ~25°C | ~36 |
| 316L (1.4404) | ~20°C | < 0°C | ~24 |
Phosphoric acid service — fertiliser production, semiconductor-grade processing, food-grade applications — is the defining use case for 1.4562. The copper addition is specifically engineered for this environment, where 316L and 904L have unacceptable attack rates.
| H₃PO₄ Concentration | Temperature | 1.4562 Corrosion Rate | Rating |
|---|---|---|---|
| 30% H₃PO₄ | 80°C | < 0.03 mm/year | Excellent |
| 55% H₃PO₄ (merchant grade) | 100°C | < 0.05 mm/year | Excellent |
| 85% H₃PO₄ (industrial) | 100°C | < 0.10 mm/year | Very Good |
| Wet-process H₃PO₄ + Cl⁻/F⁻ | 80–110°C | < 0.15 mm/year (halide-dependent) | Good — verify site Cl⁻/F⁻ |
| H₂SO₄ Concentration | Temperature | 1.4562 Rate | 904L Rate (reference) |
|---|---|---|---|
| 10% H₂SO₄ | 60°C | < 0.05 mm/year | ~0.15 mm/year |
| 30% H₂SO₄ | 80°C | < 0.10 mm/year | ~0.50 mm/year |
| 50% H₂SO₄ | 80°C | ~0.10–0.30 mm/year | > 1.0 mm/year |
| 70%+ H₂SO₄ | Any | Not recommended — use Hastelloy® B-series | |
Austenitic alloys with nickel content below ~30% are susceptible to chloride-induced SCC above 60°C. At 30–32% Ni, 1.4562 sits above this critical threshold and shows no SCC failure in boiling 42% MgCl₂ — one of the most severe laboratory screening tests — while 316L fails within hours under the same conditions.
The PREN comparison below visualises localised corrosion performance. The full comparison table covers the broader set of criteria needed for a complete grade selection decision.
| Criterion | 1.4562 | 904L | 254SMO | Hastelloy® C-276 |
|---|---|---|---|---|
| PREN | ~48–52 | ~36 | ~43 | ~65 |
| Phosphoric acid resistance | Excellent | Good | Very Good | Excellent |
| Sour service (NACE MR0175) | Yes | No | Yes | Yes |
| Hot-chloride SCC resistance | Excellent | Moderate | Good | Excellent |
| Weldability | Excellent | Good | Good | Moderate |
| PWHT required? | No | No | No | Usually No |
| Cryogenic toughness (−196°C) | Excellent | Good | Good | Good |
| Cost vs 316L | 3–4× | 2–3× | 3–4× | 8–10× |
1.4562 closes most of the performance gap with Hastelloy® C-276 at roughly one-third of the cost. For phosphoric acid ≤ 85%, sulfuric acid ≤ 50%, seawater, and sour-service applications, 1.4562 is typically the most cost-effective grade that meets service requirements with a comfortable safety margin.
Because of its ultra-low carbon content (≤ 0.015%), 1.4562 is among the more weldable super austenitic grades. No preheat is required. The principal concern is interpass temperature control: exceeding 150°C between passes promotes hot cracking and can compromise toughness in multi-pass welds.
| Welding Parameter | Requirement / Recommendation |
|---|---|
| Preheat | Not required. Ambient temperature acceptable. |
| Post-Weld Heat Treatment (PWHT) | Not required for most pressure equipment. Solution anneal at 1,150–1,180°C + rapid water quench if maximum corrosion resistance is critical after heavy fabrication. |
| Interpass Temperature | ≤ 150°C — strictly controlled to prevent sensitisation and hot cracking in multi-pass welds. |
| Recommended Filler Metal | ERNiCrMo-13 (AWS A5.14, W. Nr. 2.4668) — 1.4562-matching composition. Use over-alloyed filler when in doubt. |
| Alternative Filler (over-alloyed) | ERNiCrMo-3 (Inconel® 625 type) — preferred for maximum weld corrosion resistance or dissimilar metal joints. |
| Shielding Gas (TIG / MIG) | Pure Ar or Ar + 2% N₂. Nitrogen addition maintains austenite stability in weld metal. |
| Back Purge (TIG root pass) | Required. Pure Ar or Ar + 2% N₂. Maintain < 50 ppm O₂ to prevent root-side oxidation. |
| Heat Input | 0.5–1.5 kJ/mm (low to medium). Excessive heat input promotes grain growth and reduces toughness. |
| Post-Weld Surface | Pickling and passivation (HNO₃ + HF solution) are recommended to fully restore HAZ corrosion resistance. Mechanical polishing alone is insufficient for critical applications. |
| Applicable Standards | ASME Section IX · EN ISO 15614-1 · AWS D1.6 |
1.4562's high alloy content demands tightly controlled forging parameters to achieve the dense, uniform microstructure that maximises corrosion resistance and mechanical properties. Below is Jiangsu Liangyi's full production process for 1.4562 forged components.
Options include EAF + LF + VD (standard industrial route), EAF + ESR (electro-slag remelting for ultra-high purity), EAF + PESR (protective-atmosphere ESR), and VIM + PESR for nuclear/aerospace critical components. ESR is recommended when strict inclusion cleanliness is required for corrosion-critical applications.
Forged on 2,000T–6,300T hydraulic presses within a forging temperature window of 950°C–1,150°C. Minimum forging ratio of 3:1 to ensure complete grain refinement and elimination of cast-structure porosity. Single-piece weight from 30 kg to 30,000 kg; max forged bar diameter 2,000 mm, length up to 15,000 mm.
Produced on 1M–5M ring rolling machines. Maximum OD up to 6,000 mm, maximum single-piece weight 30 tonnes. Ring rolling creates a circumferential grain flow that maximises hoop-direction mechanical properties — critical for pressure-bearing ring components.
All 1.4562 forgings are solution-annealed at 1,150–1,180°C with temperature uniformity maintained within ±5°C, then rapidly water-quenched. The rapid quench is essential to prevent sigma-phase precipitation, which degrades both corrosion resistance and toughness.
100% ultrasonic testing (UT per ASTM A388) and 100% surface testing (liquid penetrant PT per ASTM E165 or magnetic particle MT per ASTM E709) on every piece, plus mechanical testing per ASTM E8/E10 and chemical analysis per ASTM E354. EN 10204 3.1 or 3.2 mill test certificates provided for every order.
In-house CNC turning, milling, boring, drilling, and grinding to IT6 tolerance level. Finished-to-assembly forged components supplied per customer drawings, eliminating the need for secondary machining operations at the customer's facility.
| Product Form | Max Dimensions | Max Weight |
|---|---|---|
| Forged round bars / step shafts / gear shafts | Ø up to 2,000 mm; L up to 15,000 mm | 30,000 kg |
| Seamless rolled rings / gear rings / flange blanks | OD up to 6,000 mm | 30,000 kg |
| Hollow forgings / sleeves / heavy-wall pipes | OD up to 3,000 mm | 30,000 kg |
| Forged discs / plates / tube sheets / baffles | Per customer drawing | 30,000 kg |
| Custom engineered forgings (valve bodies, pump casings, impellers, flanges…) | Per customer drawing | 30 kg – 30,000 kg |
For full specifications, available sizes, and to request a quotation, see our 1.4562 forged rings, bars, hollow forgings, and custom flanges.
1.4562 is specified wherever the combination of severe corrosion, high pressure, and long service life makes conventional alloys inadequate. The five industries below account for the large majority of global demand.
Phosphoric acid production is the single most important commercial application. Forged components include reactor nozzles, heat exchanger tube sheets, pump casings, impellers, pressure vessel shells, and valve bodies operating in wet-process H₃PO₄ environments that simultaneously contain fluoride and chloride contaminants — conditions that destroy 316L and 904L within months.
1.4562 meets the material requirements of NACE MR0175 / ISO 15156-3 for Zone 2 and Zone 3 sour service, subject to hardness ≤ 22 HRC. Custom forged components include Christmas tree bodies, wellhead spools, valve balls, bonnets, and flexible joint seals for high-H₂S Middle East, North Sea, and deepwater fields.
Flue gas desulfurisation absorber vessels and heat-exchanger components face dilute sulfuric acid condensate at elevated temperatures — exactly where 1.4562 outperforms all standard austenitic and duplex grades. Forged tube sheets, baffles, and nozzles are the primary components for this application.
With PREN ~48–52, 1.4562 shows zero tendency toward pitting corrosion in seawater at temperatures up to at least 60°C. Applications include offshore flow measurement bodies, venturi meter housings, desalination equipment, and FGD units on ocean-going vessels.
High-end valve manufacturers in Europe and North America specify 1.4562 for valve bodies, balls, bonnets, stems, and seat rings used in ball valves, gate valves, cryogenic butterfly valves, and check valves for corrosive-media service. The combination of non-magnetic properties, cryogenic toughness, and NACE qualification makes it a single-grade solution across a wide range of valve specifications.
Jiangsu Liangyi's 1.4562 forgings are produced and certified under the following standards. Third-party inspection by an inspection agency of the customer's choice is available on request for any order.
Send us your drawings, specifications, or quantity requirements. Our engineering team responds with a detailed quotation within 24 hours.