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Stainless Steel 321H-1/4 Hard vs 321H Solution Annealed

Stainless Steel · 321H temper comparison

321H-1/4 Hard and 321H Solution Annealed are two conditions of the same stainless steel grade, 321H: 1/4 Hard (quarter hard) versus Solution Annealed. The chemistry is identical, so every difference below comes from the condition. 321H-1/4 Hard is the stronger of the two: yield strength 530 MPa (76.9 ksi) against 240 MPa (34.8 ksi) for 321H Solution Annealed, about 121% more; tensile strength follows at 790 MPa (115 ksi) vs 585 MPa (84.8 ksi). In exchange, 321H Solution Annealed is the more ductile: elongation 45% versus 15% for 321H-1/4 Hard, and 321H-1/4 Hard is harder (250 HB vs 160 HB). 321H Solution Annealed runs hotter in service (900°C vs 400°C continuous).

321H-1/4 HardChoose it when strength drives the design.

321H Solution AnnealedChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

321H-1/4 Hard vs 321H Solution Annealed: properties

321H-1/4 Hard321H Solution Annealed

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

790 MPa115 ksi
585 MPa84.8 ksi

Yield Strength (0.2% offset)

530 MPa76.9 ksi
240 MPa34.8 ksi

Elongation at Break

15%
45%

Reduction in Area

45%
60%

Compressive Strength

530 MPa76.9 ksi
240 MPa34.8 ksi

Shear Strength

490 MPa71.1 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

330 MPa47.9 ksi
250 MPa36.3 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
200 MPa·√m182 ksi·√in

Charpy V-Notch Impact (RT)

75 J55.3 ft·lbf
130 J95.9 ft·lbf

Hardness, Brinell

250 HB
160 HB

Hardness, Rockwell B

100 HRB
80 HRB

Hardness, Vickers

265 HV
170 HV

Same in both: Elastic (Young's) Modulus 193 GPa28 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 152 GPa22 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Same in both: Density 7.9 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,398°C2,548 °F · Liquidus Temperature 1,427°C2,601 °F

Thermal

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

Max Service Temperature (continuous)

400°C752 °F
900°C1,652 °F

Same in both: Thermal Conductivity 16.1 W/m·K9.3 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 16.6 µm/m·K9.2 µin/in·°F · Latent Heat of Fusion 285 J/g123 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7.3×10⁻⁷ Ω·m28.7 µΩ·in
7.2×10⁻⁷ Ω·m28.3 µΩ·in

Same in both: Electrical Conductivity 2.4 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

62 / 100
64 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.05 V

Manufacturability

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

Machinability

45 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
45%

Weldability

75 / 100
82 / 100

Formability (cold)

45 / 100
78 / 100

Same in both: Brazeability / Solderability 60 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 56 MJ/kg24,076 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 160 L/kg19.2 gal/lb · Typical Recycled Content 55%

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 scale321H

321H-1/4 Hard vs 321H Solution Annealed — frequently asked

Is 321H-1/4 Hard stronger than 321H Solution Annealed?

Yes. 321H-1/4 Hard has a typical yield strength of 530 MPa (76.9 ksi) against 240 MPa (34.8 ksi) for 321H Solution Annealed — about 121% more. Tensile strength is 790 MPa (115 ksi) vs 585 MPa (84.8 ksi).

Which condition does FabDigit quote by default, 1/4 Hard or Solution Annealed?

Solution Annealed is the default 321H condition in the FabDigit quote flow. The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 321H-1/4 Hard or 321H Solution Annealed?

321H-1/4 Hard, by a small margin. Both rate fair for machinability — 45/100 against 40/100 for 321H Solution Annealed; for welding the order is 321H Solution Annealed first (very good, 82/100) then 321H-1/4 Hard (very good, 75/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 321H-1/4 Hard and 321H Solution Annealed 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.