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Steel T4-ANN vs T4-HT62

Steel · T4 temper comparison

T4-ANN and T4-HT62 are two conditions of the same steel grade, T4: ANN (annealed) versus HT62 (hardened & tempered). The chemistry is identical, so every difference below comes from the condition. T4-HT62 is the stronger of the two: yield strength 1,900 MPa (276 ksi) against 580 MPa (84.1 ksi) for T4-ANN, about 3.3 times as much; tensile strength follows at 2,100 MPa (305 ksi) vs 950 MPa (138 ksi). In exchange, T4-ANN is the more ductile: elongation 12% versus 0.5% for T4-HT62, and T4-HT62 is harder (790 HV vs 265 HV). T4-HT62 runs hotter in service (600°C vs 500°C continuous) and T4-ANN conducts heat better (24 W/m·K vs 21 W/m·K). On the shop floor, T4-ANN machines more easily (poor vs not recommended) and T4-ANN welds better (poor vs not recommended).

T4-ANNChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

T4-HT62Choose it when strength drives the design, or when the part sees heat.

T4-ANN vs T4-HT62: properties

T4-ANNT4-HT62

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

215 GPa31.2 Msi
220 GPa31.9 Msi

Tensile Strength (Ultimate)

950 MPa138 ksi
2,100 MPa305 ksi

Yield Strength (0.2% offset)

580 MPa84.1 ksi
1,900 MPa276 ksi

Elongation at Break

12%
0.5%

Compressive Strength

900 MPa131 ksi
3,300 MPa479 ksi

Shear Strength

600 MPa87 ksi
1,500 MPa218 ksi

Fatigue Strength (Endurance Limit)

430 MPa62.4 ksi
780 MPa113 ksi

Charpy V-Notch Impact (RT)

18 J13.3 ft·lbf
4 J3 ft·lbf

Hardness, Vickers

265 HV
790 HV

Same in both: Shear Modulus 84 GPa12.2 Msi · Bulk Modulus 165 GPa23.9 Msi · Poisson's Ratio 0.29 · Reduction in Area 25% · Hardness, Brinell 255 HB · Hardness, Rockwell B 100 HRB

Physical

Density and transition temperatures.

Same in both: Density 8.75 g/cm³0.32 lb/in³ · Melting Point (Solidus) 1,260°C2,300 °F · Liquidus Temperature 1,430°C2,606 °F

Thermal

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

Thermal Conductivity

24 W/m·K13.9 BTU/hr·ft·°F
21 W/m·K12.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

500°C932 °F
600°C1,112 °F

Same in both: Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.2 µm/m·K6.2 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -60°C-76 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

3 % IACS
2.7 % IACS

Electrical Resistivity

5.7×10⁻⁷ Ω·m22.4 µΩ·in
6.4×10⁻⁷ Ω·m25.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.5 V · Corrosion Resistance 18 / 100

Manufacturability

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

Machinability

30 / 100
5 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
5%

Weldability

20 / 100
10 / 100

Formability (cold)

10 / 100
0 / 100

Same in both: Castability 25 / 100 · Brazeability / Solderability 55 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 75 MJ/kg32,244 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 120 L/kg14.4 gal/lb · Typical Recycled Content 35%

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 scaleT4

T4-ANN vs T4-HT62 — frequently asked

Is T4-HT62 stronger than T4-ANN?

Yes. T4-HT62 has a typical yield strength of 1,900 MPa (276 ksi) against 580 MPa (84.1 ksi) for T4-ANN — about 3.3 times as much. Tensile strength is 2,100 MPa (305 ksi) vs 950 MPa (138 ksi).

Which condition does FabDigit quote by default, ANN or HT62?

ANN is the default T4 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, T4-ANN or T4-HT62?

T4-ANN. Its machinability rates poor (30/100) against not recommended (5/100) for T4-HT62; for welding the order is T4-ANN first (poor, 20/100) then T4-HT62 (not recommended, 10/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in T4-ANN and T4-HT62 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.