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Stainless Steel 904L · temper

Stainless Steel 904L Annealed

Properties of the Annealed condition, compared with the other 904L tempers.

Hot-finished bar, billet and forgings supplied annealed; same corrosion performance, slightly lower strength than cold-worked forms.

CNC machiningSheet metalPremium cost $$$

What is 904L Annealed?

904L Annealed is 904L in the Annealed temper — hot-finished bar, billet and forgings supplied annealed; same corrosion performance, slightly lower strength than cold-worked forms. 904L Annealed has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi). 904L 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). Solution Annealed is the default condition FabDigit quotes; Annealed is available on request or by drawing note.

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
  • Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades

Limitations

  • Low strength — 240 MPa (34.8 ksi), worse than 96% of stainless steel grades
  • 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
  • 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 Annealed properties

Typical room-temperature values for 904L Annealed — 8 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 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).

Density8 g/cm³0.29 lb/in³
Melting Point (Solidus)1,300°C2,372 °F
Liquidus Temperature1,390°C2,534 °F

Mechanical16

904L Annealed has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 195 GPa (28.3 Msi).

Elastic (Young's) Modulus195 GPa28.3 Msi
Shear Modulus75 GPa10.9 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)560 MPa81.2 ksi
Yield Strength (0.2% offset)240 MPa34.8 ksi
Elongation at Break45%
Reduction in Area65%
Compressive Strength265 MPa38.4 ksi
Shear Strength390 MPa56.6 ksi
Fatigue Strength (Endurance Limit)240 MPa34.8 ksi
Fracture Toughness (K_IC)200 MPa·√m182 ksi·√in
Charpy V-Notch Impact (RT)190 J140 ft·lbf
Hardness, Brinell150 HB
Hardness, Rockwell B78 HRB
Hardness, Vickers165 HV

Thermal6

904L 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).

Thermal Conductivity12 W/m·K6.9 BTU/hr·ft·°F
Specific Heat Capacity450 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)15.3 µm/m·K8.5 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)400°C752 °F
Min Service Temperature-196°C-321 °F

Electrical3

904L Annealed conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.

Electrical Conductivity1.7 % IACS
Electrical Resistivity1×10⁻⁶ Ω·m39.4 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (82/100), better than 90% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.05 V
Corrosion ResistanceVery good82/100
Chemical Resistance SummaryExcellent in dilute to intermediate sulfuric acid (Cu addition), phosphoric acid, organic acids and chloride-bearing waters; resists pitting/crevice attack and chloride SCC far better than 316L. Not for hot concentrated hydrochloric acid, oxidizing chloride media (FeCl₃ above ~35 °C) or strong reducing HF; limited in high-temperature service due to sigma-phase.

Sustainability4

Producing a kilogram of 904L 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%.

Embodied Energy (primary production)78 MJ/kg33,534 BTU/lb
Embodied Carbon (primary production)5.6 kg CO₂/kg
Embodied Water200 L/kg24 gal/lb
Typical Recycled Content55%

Manufacturability7

904L Annealed's machinability is poor (28/100, worse than 80% of stainless steel grades); weldability very good (78/100); formability very good (72/100).

MachinabilityPoor28/100
Machinability Rating (AISI 1212 = 100 %)30%
WeldabilityVery good78/100
Formability (cold)Very good72/100
Brazeability / SolderabilityGood55/100
PolishabilityVery good78/100
Anodizing Responsen/a — ferrous alloy; use pickling and passivation (nitric or citric) or electropolishing instead

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.

Working with 904L 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.

ElementSpec limit (wt %)Nominal
Cextra-low carbon≤ 0.020.01
SiEN 1.4539 limits Si ≤ 0.70≤ 10.4
Mn≤ 21.4
PEN 1.4539: ≤ 0.030≤ 0.050.03
SEN 1.4539: ≤ 0.010≤ 0.040
Cr19 – 2320
Ni23 – 2825
Mo4 – 54.5
Cuimproves resistance in sulfuric acid1 – 21.5
NEN 1.4539 limit≤ 0.10.05
Febalance

904L Annealed — frequently asked

What is 904L Annealed used for?

904L 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 Annealed?

904L Annealed has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 96% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.

Is 904L 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 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 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 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 Annealed?

904L 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 Annealed?

Yes — 904L 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

  1. ASTM A240/A240M — Cr and Cr-Ni Stainless Plate, Sheet and StripASTM International (2023)
  2. ASTM B625 / B649 — UNS N08904 plate, sheet, strip and barASTM International (2022)
  3. EN 10088-1/-2 — Stainless steels, grade 1.4539 (X1NiCrMoCu25-20-5)CEN (2014)
  4. 904L / 1.4539 super-austenitic stainless datasheetOutokumpu (2023)
  5. Sanicro 28 / 904L-type alloy technical dataAlleima (Sandvik) (2022)
  6. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance AlloysASM 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.