Steel H42-ANN vs H42 HT-NIT
Steel · H42 temper comparison
H42-ANN and H42 HT-NIT are two conditions of the same steel grade, H42: ANN (annealed) versus HT-NIT (hardened, tempered and gas/plasma nitrided surface). The chemistry is identical, so every difference below comes from the condition. H42 HT-NIT is the stronger of the two: yield strength 1,600 MPa (232 ksi) against 550 MPa (79.8 ksi) for H42-ANN, about 191% more; tensile strength follows at 1,900 MPa (276 ksi) vs 830 MPa (120 ksi). In exchange, H42-ANN is the more ductile: elongation 16% versus 5% for H42 HT-NIT, and H42 HT-NIT is harder (1,050 HV vs 235 HV). H42 HT-NIT runs hotter in service (600°C vs 400°C continuous). On the shop floor, H42-ANN machines more easily (poor vs not recommended) and H42-ANN welds better (poor vs not recommended).
H42-ANNChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
H42 HT-NITChoose it when strength drives the design, or when the part sees heat.
H42-ANN vs H42 HT-NIT: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 223 HB · Hardness, Rockwell B 97 HRB
Physical
Density and transition temperatures.
Same in both: Density 8.06 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,370°C2,498 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.3 µm/m·K6.3 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Brazeability / Solderability 40 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 42 MJ/kg18,057 BTU/lb · Embodied Carbon (primary production) 3.1 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 40%
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.
H42-ANN vs H42 HT-NIT — frequently asked
Is H42 HT-NIT stronger than H42-ANN?
Yes. H42 HT-NIT has a typical yield strength of 1,600 MPa (232 ksi) against 550 MPa (79.8 ksi) for H42-ANN — about 191% more. Tensile strength is 1,900 MPa (276 ksi) vs 830 MPa (120 ksi).
Which condition does FabDigit quote by default, ANN or HT-NIT?
ANN is the default H42 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, H42-ANN or H42 HT-NIT?
H42-ANN. Its machinability rates poor (32/100) against not recommended (3/100) for H42 HT-NIT; for welding the order is H42-ANN first (poor, 25/100) then H42 HT-NIT (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in H42-ANN and H42 HT-NIT 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.