Stainless Steel 904L · heat-treated state · default condition
Stainless Steel 904L Solution Annealed
Properties of the Solution Annealed condition, compared with the other 904L tempers.
Standard supply condition for all corrosion-service product forms — maximum corrosion resistance and ductility.
What is 904L Solution Annealed?
904L Solution Annealed is 904L heat treated to Solution Annealed — standard supply condition for all corrosion-service product forms — maximum corrosion resistance and ductility. 904L Solution Annealed has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 195 GPa (28.3 Msi). 904L Solution Annealed has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Advantages
- Good corrosion resistance — 82/100, better than 90% of stainless steel grades
- Tough — resists crack growth — 200 MPa·√m (182 ksi·√in), better than 84% of stainless steel grades
- Forms and bends easily — 72/100, better than 83% of stainless steel grades
Limitations
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- Poor heat conductor — 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 92% of stainless steel grades
- Low strength — 260 MPa (37.7 ksi), worse than 84% of stainless steel grades
- High embodied carbon — 5.6 kg CO₂/kg, worse than 82% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
904L Solution Annealed properties
Typical room-temperature values for 904L Solution Annealed — 10 properties are specific to this condition; the rest are grade-level values shared by every 904L temper. Each bar shows where the value sits among the stainless steel grades in FabDigit's library — further right is higher.
Physical3
904L Solution Annealed has a density of 8 g/cm³ (0.289 lb/in³), heavier than 92% of stainless steel grades. It melts at 1,300°C (2,372 °F).
Mechanical16
904L Solution Annealed has a yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
904L Solution Annealed is rated for continuous service to 400°C (752 °F). It conducts heat at 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 92% of stainless steel grades. Thermal expansion is 15.3 µm/m·K (8.5 µin/in·°F).
Electrical3
904L Solution Annealed conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 90% of stainless steel grades.
Sustainability4
Producing a kilogram of 904L Solution Annealed takes about 78 MJ of energy and emits 5.6 kg of CO₂ — more than 87% of stainless steel grades. Typical recycled content is 55%.
Manufacturability7
904L Solution Annealed's machinability is poor (28/100, worse than 80% of stainless steel grades); weldability very good (78/100); formability very good (72/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 904L tempers and conditions
904L is also supplied in 3 other conditions. The full side-by-side table is on the 904L overview.
- Solution AnnealedDefaultStandard supply condition for all corrosion-service product forms — maximum corrosion resistance and ductility.260 MPa yield · 155 HB
- Cold Rolled HardStrip/sheet supplied work hardened for springs, gaskets and stamped parts needing higher strength; solution anneal after severe forming for best corrosion resistance.620 MPa yield · 26 HRC
- Cold DrawnChoose for tight tolerance shafts, fasteners and small-bore tube where higher yield strength and better surface finish are needed.550 MPa yield · 230 HB
- AnnealedHot-finished bar, billet and forgings supplied annealed; same corrosion performance, slightly lower strength than cold-worked forms.240 MPa yield · 150 HB
Working with 904L Solution Annealed
Is 904L easy to machine?
Gummy and strongly work hardening — use rigid setups, positive-rake coated carbide, low speed / heavy positive feed, generous flood coolant and avoid dwelling or re-cutting in the hardened layer.
Can 904L be welded?
Readily welded by GTAW/GMAW/SMAW with no preheat and low interpass temperature; use overalloyed filler (ER/E 385 = 904L-type or Ni-base 625/C-276) to avoid Mo-depleted dendrite cores, and keep heat input low with backing gas.
Can 904L be formed, bent or molded?
Very ductile but needs ~50% higher forming loads than 304 with strong springback; hot work 1150–900 °C then solution anneal and quench to restore corrosion resistance.
What surface finishes work on 904L?
Pickle and passivate (nitric or citric) after welding, remove all heat tint by grinding/blasting or pickling paste; electropolishes to low-Ra hygienic finishes and cannot be anodized.
904L 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 | ≤ 0.02 | 0.01 |
| SiEN 1.4539 limits Si ≤ 0.70 | ≤ 1 | 0.4 |
| Mn | ≤ 2 | 1.4 |
| PEN 1.4539: ≤ 0.030 | ≤ 0.05 | 0.03 |
| SEN 1.4539: ≤ 0.010 | ≤ 0.04 | 0 |
| Cr | 19 – 23 | 20 |
| Ni | 23 – 28 | 25 |
| Mo | 4 – 5 | 4.5 |
| Cuimproves resistance in sulfuric acid | 1 – 2 | 1.5 |
| NEN 1.4539 limit | ≤ 0.1 | 0.05 |
| Fe | balance | — |
904L Solution Annealed — frequently asked
What is 904L Solution Annealed used for?
904L Solution Annealed is typically used for sulfuric acid pumps and valves, pickling line tanks and fixtures, phosphoric acid heat exchangers, flue-gas desulfurization scrubbers, chemical process piping and vessels and seawater condenser tubing. In short: super-austenitic chemical stainless.
What is the yield strength of 904L Solution Annealed?
904L Solution Annealed has a typical yield strength of 260 MPa (37.7 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 84% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 904L Solution Annealed easy to machine?
Not especially — machinability is rated poor (28/100, worse than 80% of stainless steel grades). Gummy and strongly work hardening — use rigid setups, positive-rake coated carbide, low speed / heavy positive feed, generous flood coolant and avoid dwelling or re-cutting in the hardened layer.
Can 904L Solution Annealed be welded?
Yes — weldability is rated very good (78/100). Readily welded by GTAW/GMAW/SMAW with no preheat and low interpass temperature; use overalloyed filler (ER/E 385 = 904L-type or Ni-base 625/C-276) to avoid Mo-depleted dendrite cores, and keep heat input low with backing gas.
What surface finishes work on 904L Solution Annealed?
Pickle and passivate (nitric or citric) after welding, remove all heat tint by grinding/blasting or pickling paste; electropolishes to low-Ra hygienic finishes and cannot be anodized.
Can 904L Solution Annealed be formed, bent or molded?
Very ductile but needs ~50% higher forming loads than 304 with strong springback; hot work 1150–900 °C then solution anneal and quench to restore corrosion resistance.
What is the maximum service temperature of 904L Solution Annealed?
904L Solution Annealed is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 904L Solution Annealed?
Yes — 904L Solution Annealed is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A240/A240M — Cr and Cr-Ni Stainless Plate, Sheet and Strip — ASTM International (2023)
- ASTM B625 / B649 — UNS N08904 plate, sheet, strip and bar — ASTM International (2022)
- EN 10088-1/-2 — Stainless steels, grade 1.4539 (X1NiCrMoCu25-20-5) — CEN (2014)
- 904L / 1.4539 super-austenitic stainless datasheet — Outokumpu (2023)
- Sanicro 28 / 904L-type alloy technical data — Alleima (Sandvik) (2022)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
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.