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Stainless Steel 304 vs RA85H

Stainless Steel · grade comparison

Stainless Steel 304 and RA85H are both stainless steel grades. RA85H is the stronger of the two: yield strength 345 MPa (50 ksi) against 250 MPa (36.3 ksi) for 304, about 38% more; tensile strength follows at 655 MPa (95 ksi) vs 585 MPa (84.8 ksi). In exchange, 304 is the more ductile: elongation 55% versus 45% for RA85H, and RA85H is harder (180 HB vs 150 HB). RA85H is lighter (7.72 g/cm³ vs 8 g/cm³ for 304) and RA85H runs hotter in service (1,095°C vs 870°C continuous). On the shop floor, 304 machines more easily (fair vs poor), 304 welds better (excellent vs good), and 304 sits in a lower cost tier (standard, $$) than RA85H (high, $$$$).

304Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

RA85HChoose it when strength drives the design, or when weight is the constraint.

304 vs RA85H: properties

304RA85H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

193 GPa28 Msi
196 GPa28.4 Msi

Shear Modulus

77 GPa11.2 Msi
76 GPa11 Msi

Bulk Modulus

152 GPa22 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

585 MPa84.8 ksi
655 MPa95 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
345 MPa50 ksi

Elongation at Break

55%
45%

Reduction in Area

70%
55%

Compressive Strength

250 MPa36.3 ksi
345 MPa50 ksi

Shear Strength

415 MPa60.2 ksi
440 MPa63.8 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

220 MPa·√m200 ksi·√in
200 MPa·√m182 ksi·√in

Charpy V-Notch Impact (RT)

200 J148 ft·lbf
110 J81.1 ft·lbf

Hardness, Brinell

150 HB
180 HB

Hardness, Rockwell B

82 HRB
88 HRB

Hardness, Vickers

160 HV
190 HV

Same in both: Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

8 g/cm³0.29 lb/in³
7.72 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,400°C2,552 °F
1,350°C2,462 °F

Liquidus Temperature

1,450°C2,642 °F
1,400°C2,552 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

16.2 W/m·K9.4 BTU/hr·ft·°F
12.6 W/m·K7.3 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

17.3 µm/m·K9.6 µin/in·°F
15.6 µm/m·K8.7 µin/in·°F

Latent Heat of Fusion

285 J/g123 BTU/lb
—

Max Service Temperature (continuous)

870°C1,598 °F
1,095°C2,003 °F

Min Service Temperature

-196°C-321 °F
—

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.4 % IACS
1.7 % IACS

Electrical Resistivity

7.2×10⁻⁷ Ω·m28.3 µΩ·in
1×10⁻⁶ Ω·m39.4 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.05 V
-0.1 V

Corrosion Resistance

70 / 100
62 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

45 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
32%

Weldability

88 / 100
55 / 100

Formability (cold)

90 / 100
55 / 100

Brazeability / Solderability

65 / 100
55 / 100

Polishability

88 / 100
60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Carbon (primary production)

5.4 kg CO₂/kg
5.2 kg CO₂/kg

Embodied Water

110 L/kg13.2 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

70%
60%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

73 kN·m/kg
85 kN·m/kg

Specific Stiffness (E / density)

24.1 MN·m/kg
25.4 MN·m/kg

Modulus of Resilience

162 kJ/m³
304 kJ/m³

Thermal Diffusivity

4.1 mm²/s
3.3 mm²/s

Same in both: Thermal Shock Resistance Index 3

Strength versus weight

Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scale304RA85H

Manufacturing and finishing

Capability304RA85H
CNC machiningYes—
Sheet metalYes—
Casting & forgingYes—
Default conditionAnnealed—
Relative cost$$ Standard$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Passivation (Stainless Steel)Yes—

They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

304 vs RA85H — frequently asked

Is RA85H stronger than 304?

Yes. RA85H has a typical yield strength of 345 MPa (50 ksi) against 250 MPa (36.3 ksi) for 304 — about 38% more. Tensile strength is 655 MPa (95 ksi) vs 585 MPa (84.8 ksi).

Which is cheaper, 304 or RA85H?

304 is the lower-cost material: it sits in the standard tier ($$) while RA85H is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, 304 or RA85H?

304. Its machinability rates fair (45/100) against poor (28/100) for RA85H; for welding the order is 304 first (excellent, 88/100) then RA85H (good, 55/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 304 and RA85H side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.