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Steel H19 vs H21

Steel · grade comparison

Steel H19 and H21 are both steel grades. H21 is the stronger of the two: yield strength 620 MPa (89.9 ksi) against 520 MPa (75.4 ksi) for H19, about 19% more; tensile strength follows at 900 MPa (131 ksi) vs 800 MPa (116 ksi). H19 is harder — 20 HRC against 19 HRC for H21 — which matters for wear surfaces and threads. H21 runs hotter in service (450°C vs 400°C continuous) and H21 conducts heat better (27 W/m·K vs 24 W/m·K). On the shop floor, H21 sits in a lower cost tier (standard, $$) than H19 (high, $$$$).

H19Choose it when surface hardness matters.

H21Choose it when strength drives the design, or when the part sees heat.

H19 vs H21: properties

H19H21

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

165 GPa23.9 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

800 MPa116 ksi
900 MPa131 ksi

Yield Strength (0.2% offset)

520 MPa75.4 ksi
620 MPa89.9 ksi

Compressive Strength

540 MPa78.3 ksi
650 MPa94.3 ksi

Shear Strength

480 MPa69.6 ksi
550 MPa79.8 ksi

Fatigue Strength (Endurance Limit)

360 MPa52.2 ksi
400 MPa58 ksi

Charpy V-Notch Impact (RT)

22 J16.2 ft·lbf
25 J18.4 ft·lbf

Hardness, Rockwell C

20 HRC
19 HRC

Hardness, Vickers

231 HV
230 HV

Fracture Toughness (K_IC)

—
55 MPa·√m50.1 ksi·√in

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Poisson's Ratio 0.29 · Elongation at Break 18% · Reduction in Area 40% · Hardness, Brinell 220 HB · Hardness, Rockwell B 97 HRB

Physical

Density and transition temperatures.

Density

8.19 g/cm³0.3 lb/in³
8.28 g/cm³0.3 lb/in³

Melting Point (Solidus)

1,370°C2,498 °F
1,420°C2,588 °F

Liquidus Temperature

1,450°C2,642 °F
1,480°C2,696 °F

Thermal

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

Thermal Conductivity

24 W/m·K13.9 BTU/hr·ft·°F
27 W/m·K15.6 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.2 µm/m·K6.2 µin/in·°F
11.8 µm/m·K6.6 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
450°C842 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.7 % IACS
3.1 % IACS

Electrical Resistivity

6.5×10⁻⁷ Ω·m25.6 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.55 V
—

Same in both: Corrosion Resistance 15 / 100

Manufacturability

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

Machinability

35 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

38%
45%

Weldability

30 / 100
35 / 100

Formability (cold)

25 / 100
20 / 100

Castability

20 / 100
30 / 100

Brazeability / Solderability

35 / 100
40 / 100

Polishability

55 / 100
65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

45 MJ/kg19,347 BTU/lb
42 MJ/kg18,057 BTU/lb

Embodied Carbon (primary production)

3.2 kg CO₂/kg
3 kg CO₂/kg

Embodied Water

70 L/kg8.4 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

40%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

98 kN·m/kg
109 kN·m/kg

Specific Stiffness (E / density)

25.6 MN·m/kg
25.4 MN·m/kg

Modulus of Resilience

644 kJ/m³
915 kJ/m³

Thermal Diffusivity

6.4 mm²/s
7.1 mm²/s

Thermal Shock Resistance Index

8
10

Strength versus weight

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

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleH21H19

Manufacturing and finishing

CapabilityH19H21
CNC machining—Yes
Default condition—Annealed
Relative cost$$$$ High$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

H19 vs H21 — frequently asked

Is H21 stronger than H19?

Yes. H21 has a typical yield strength of 620 MPa (89.9 ksi) against 520 MPa (75.4 ksi) for H19 — about 19% more. Tensile strength is 900 MPa (131 ksi) vs 800 MPa (116 ksi).

Which is cheaper, H19 or H21?

H21 is the lower-cost material: it sits in the standard tier ($$) while H19 is high ($$$$). 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, H19 or H21?

H21, by a small margin. Both rate fair for machinability — 40/100 against 35/100 for H19; for welding the order is H21 first (fair, 35/100) then H19 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in H19 and H21 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.