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Stainless Steel 420C +A vs 420C-H

Stainless Steel · 420C temper comparison

420C +A and 420C-H are two conditions of the same stainless steel grade, 420C: +A (annealed) versus H (hardened). The chemistry is identical, so every difference below comes from the condition. 420C-H is the stronger of the two: yield strength 1,600 MPa (232 ksi) against 460 MPa (66.7 ksi) for 420C +A, about 3.5 times as much; tensile strength follows at 1,950 MPa (283 ksi) vs 760 MPa (110 ksi). In exchange, 420C +A is the more ductile: elongation 17% versus 1% for 420C-H, and 420C-H is harder (615 HB vs 220 HB). 420C +A runs hotter in service (400°C vs 200°C continuous) and 420C +A conducts heat better (30 W/m·K vs 24 W/m·K). On the shop floor, 420C +A machines more easily (fair vs not recommended) and 420C +A welds better (poor vs not recommended).

420C +AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

420C-HChoose it when strength drives the design.

420C +A vs 420C-H: properties

420C +A420C-H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

760 MPa110 ksi
1,950 MPa283 ksi

Yield Strength (0.2% offset)

460 MPa66.7 ksi
1,600 MPa232 ksi

Elongation at Break

17%
1%

Reduction in Area

40%
2%

Compressive Strength

470 MPa68.2 ksi
2,000 MPa290 ksi

Shear Strength

460 MPa66.7 ksi
1,150 MPa167 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
750 MPa109 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
15 MPa·√m13.7 ksi·√in

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
5 J3.7 ft·lbf

Hardness, Brinell

220 HB
615 HB

Hardness, Rockwell C

20 HRC
57 HRC

Hardness, Vickers

230 HV
660 HV

Same in both: Elastic (Young's) Modulus 215 GPa31.2 Msi · Shear Modulus 83 GPa12 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.28 · Hardness, Rockwell B 97 HRB

Physical

Density and transition temperatures.

Same in both: Density 7.7 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

30 W/m·K17.3 BTU/hr·ft·°F
24 W/m·K13.9 BTU/hr·ft·°F

Max Service Temperature (continuous)

400°C752 °F
200°C392 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.5 µm/m·K5.8 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3.1 % IACS
2.5 % IACS

Electrical Resistivity

5.5×10⁻⁷ Ω·m21.7 µΩ·in
7×10⁻⁷ Ω·m27.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

42 / 100
50 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.35 V

Manufacturability

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

Machinability

45 / 100
8 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
8%

Weldability

20 / 100
5 / 100

Formability (cold)

30 / 100
0 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 45 / 100 · Polishability 78 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 50 MJ/kg21,496 BTU/lb · Embodied Carbon (primary production) 3.4 kg CO₂/kg · Embodied Water 90 L/kg10.8 gal/lb · Typical Recycled Content 45%

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 scale420C

420C +A vs 420C-H — frequently asked

Is 420C-H stronger than 420C +A?

Yes. 420C-H has a typical yield strength of 1,600 MPa (232 ksi) against 460 MPa (66.7 ksi) for 420C +A — about 3.5 times as much. Tensile strength is 1,950 MPa (283 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, +A or H?

+A is the default 420C 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, 420C +A or 420C-H?

420C +A. Its machinability rates fair (45/100) against not recommended (8/100) for 420C-H; for welding the order is 420C +A first (poor, 20/100) then 420C-H (not recommended, 5/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 420C +A and 420C-H 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.