Steel H43-ANN vs H43-QT58
Steel · H43 temper comparison
H43-ANN and H43-QT58 are two conditions of the same steel grade, H43: ANN (annealed) versus QT58 (hardened & tempered to 58–60 HRC). The chemistry is identical, so every difference below comes from the condition. H43-QT58 is the stronger of the two: yield strength 1,850 MPa (268 ksi) against 520 MPa (75.4 ksi) for H43-ANN, about 3.6 times as much; tensile strength follows at 2,150 MPa (312 ksi) vs 760 MPa (110 ksi). In exchange, H43-ANN is the more ductile: elongation 18% versus 2% for H43-QT58, and H43-QT58 is harder (675 HV vs 240 HV). H43-QT58 runs hotter in service (590°C vs 400°C continuous). On the shop floor, H43-ANN machines more easily (fair vs not recommended) and H43-ANN welds better (poor vs not recommended).
H43-ANNChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
H43-QT58Choose it when strength drives the design, or when the part sees heat.
H43-ANN vs H43-QT58: 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)
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 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 229 HB · Hardness, Rockwell B 98 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.95 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,455°C2,651 °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 -30°C-22 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3.1 % IACS · Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.45 V · Corrosion Resistance 16 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Polishability
Same in both: Castability 25 / 100 · Brazeability / Solderability 35 / 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 45%
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.
H43-ANN vs H43-QT58 — frequently asked
Is H43-QT58 stronger than H43-ANN?
Yes. H43-QT58 has a typical yield strength of 1,850 MPa (268 ksi) against 520 MPa (75.4 ksi) for H43-ANN — about 3.6 times as much. Tensile strength is 2,150 MPa (312 ksi) vs 760 MPa (110 ksi).
Which condition does FabDigit quote by default, ANN or QT58?
ANN is the default H43 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, H43-ANN or H43-QT58?
H43-ANN. Its machinability rates fair (35/100) against not recommended (5/100) for H43-QT58; for welding the order is H43-ANN first (poor, 25/100) then H43-QT58 (not recommended, 10/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in H43-ANN and H43-QT58 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.