Stainless Steel 1.4590-AW (As-welded deposit)
Heat-treated state
EN 1.4590
Property set for welded joints: Nb+Zr stabilisation keeps the HAZ ductile and immune to intergranular attack without post-weld annealing.
Values for the AW condition
Other 1.4590 tempers and conditions
1.4590 is listed in 3 conditions; see the grade overview at 1.4590.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AWThis page As-welded deposit | Property set for welded joints: Nb+Zr stabilisation keeps the HAZ ductile and immune to intergranular attack without post-weld annealing. | 285 | 455 | 22 | 162 HB | 2.9 % IACS |
ADefault Solution annealed | Standard stocked condition for exhaust and heat-transfer sheet: maximum ductility and best formability. | 290 | 470 | 30 | 155 HB | — |
CW 1/4-Hard | Light cold work for higher yield strength and improved flatness/springiness where deep drawing is not needed. | 450 | 560 | 15 | 13 HRC | 2.9 % IACS |
What is 1.4590-AW?
1.4590-AW is 1.4590 heat treated to AW — property set for welded joints: Nb+Zr stabilisation keeps the HAZ ductile and immune to intergranular attack without post-weld annealing. 1.4590-AW has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 455 MPa (66 ksi) — weaker than 74% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 220 GPa (31.9 Msi). 1.4590-AW has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F). A is the default condition FabDigit quotes; AW is available on request or by drawing note.
Advantages
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- Low embodied carbon — 3.4 kg CO₂/kg, better than 91% of stainless steel grades
- High electrical conductivity — 2.9 % IACS, better than 87% of stainless steel grades
- High service temperature — 900°C (1,652 °F), better than 85% of stainless steel grades
- Easy to machine — 45/100, better than 84% of stainless steel grades
Limitations
- Limited ductility — 22%, worse than 75% of stainless steel grades
1.4590-AW properties
Typical room-temperature values for 1.4590-AW; 20 are specific to this condition. Other listed values are 1.4590 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4590-AW has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
1.4590-AW has a yield strength of 285 MPa (41.3 ksi) and a tensile strength of 455 MPa (66 ksi) — weaker than 74% of stainless steel grades. Elongation at break is 22% and the elastic modulus is 220 GPa (31.9 Msi).
Thermal6
1.4590-AW is rated for continuous service to 900°C (1,652 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10 µm/m·K (5.56 µin/in·°F).
Electrical3
1.4590-AW conducts electricity at 2.9 % IACS, better than 87% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (53/100), worse than 75% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4590-AW takes about 52 MJ of energy and emits 3.4 kg of CO₂ — less than 76% of stainless steel grades. Typical recycled content is 70%.
Manufacturability7
1.4590-AW's machinability is fair (45/100, better than 84% of stainless steel grades); weldability very good (80/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4590-AW
Is 1.4590 easy to machine?
Machines like 430/439 — use sharp positive-rake carbide, rigid setup, generous coolant and moderate speed to avoid built-up edge and work-hardened skin.
Can 1.4590 be welded?
Excellent: TIG/MIG/laser and resistance welding without post-weld anneal; Nb+Zr prevents sensitisation, use Ar (+He) shielding, low heat input and back purging to limit grain coarsening.
Can 1.4590 be formed, bent or molded?
Good deep-drawability and low springback versus austenitics; anisotropy is modest, but bend radii should be ≥1t and heavily cold-worked edges deburred before forming.
What surface finishes work on 1.4590?
Passivate or electropolish after pickling; can be brushed, bright-annealed or Ni/Cr plated — do not anodise; protect from carbon-steel contamination to avoid rust staining.
1.4590 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cextra-low carbon | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1 | 0.4 |
| P | ≤ 0.04 | 0.03 |
| S | ≤ 0.02 | 0 |
| Cr | 16 – 17.5 | 16.8 |
| Nbprimary stabiliser; Nb+Zr set to ≥12×(C+N) per EN 10088-2 | 0.2 – 1 | 0.45 |
| Zrco-stabiliser, refines weld-metal grain | 0.05 – 0.6 | 0.2 |
| N | ≤ 0.03 | 0.02 |
| Fe | balance | — |
1.4590-AW — frequently asked
What is 1.4590-AW used for?
1.4590-AW is typically used for automotive exhaust systems, catalytic converter housings, heat shields and tubing. In short: dual-stabilised Nb+Zr ferritic; 900 °C exhaust grade; sensitisation-free welds.
What is the yield strength of 1.4590-AW?
1.4590-AW has a typical yield strength of 285 MPa (41.3 ksi) and a tensile strength of 455 MPa (66 ksi) — weaker than 74% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4590-AW easy to machine?
Reasonably — machinability is rated fair (45/100, better than 84% of stainless steel grades). Machines like 430/439 — use sharp positive-rake carbide, rigid setup, generous coolant and moderate speed to avoid built-up edge and work-hardened skin.
Can 1.4590-AW be welded?
Yes — weldability is rated very good (80/100). Excellent: TIG/MIG/laser and resistance welding without post-weld anneal; Nb+Zr prevents sensitisation, use Ar (+He) shielding, low heat input and back purging to limit grain coarsening.
What surface finishes work on 1.4590-AW?
Passivate or electropolish after pickling; can be brushed, bright-annealed or Ni/Cr plated — do not anodise; protect from carbon-steel contamination to avoid rust staining.
Can 1.4590-AW be formed, bent or molded?
Good deep-drawability and low springback versus austenitics; anisotropy is modest, but bend radii should be ≥1t and heavily cold-worked edges deburred before forming.
What is the maximum service temperature of 1.4590-AW?
1.4590-AW is rated for continuous use to about 900°C (1,652 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4590-A and 1.4590-AW?
A is the default condition — standard stocked condition for exhaust and heat-transfer sheet: maximum ductility and best formability. AW: property set for welded joints: Nb+Zr stabilisation keeps the HAZ ductile and immune to intergranular attack without post-weld annealing. Yield strength is 290 MPa in A versus 285 MPa in AW.
Sources
- EN 10088-1 Stainless steels — List of stainless steels — CEN (2014)
- EN 10088-2 Stainless steels — Technical delivery conditions for sheet/plate and strip for corrosion resisting purposes — CEN (2014)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Stabilised ferritic stainless steels for automotive exhaust systems — Outokumpu / Aperam (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.