Steel A8 H&T 56-58 HRC vs A8 Q&T
Steel · A8 temper comparison
A8 H&T 56-58 HRC and A8 Q&T are two conditions of the same steel grade, A8: H&T 56-58 HRC (high-temper, maximum-toughness condition) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. A8 Q&T is the stronger of the two: yield strength 1,700 MPa (247 ksi) against 1,600 MPa (232 ksi) for A8 H&T 56-58 HRC, about 6% more; tensile strength follows at 2,000 MPa (290 ksi) vs 1,900 MPa (276 ksi). In exchange, A8 H&T 56-58 HRC is the more ductile: elongation 18% versus 2% for A8 Q&T, and A8 Q&T is harder (675 HV vs 630 HV). A8 H&T 56-58 HRC runs hotter in service (480°C vs 425°C continuous).
A8 H&T 56-58 HRCChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
A8 Q&TChoose it when strength drives the design.
A8 H&T 56-58 HRC vs A8 Q&T: 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
Compressive Strength
Shear Strength
Charpy V-Notch Impact (RT)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 207 GPa30 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Reduction in Area 40% · Hardness, Brinell 220 HB
Physical
Density and transition temperatures.
Same in both: Density 7.83 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,470°C2,678 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 24.5 W/m·K14.2 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.4 µm/m·K6.9 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 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Corrosion Resistance 20 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Same in both: Weldability 20 / 100 · Formability (cold) 20 / 100 · Brazeability / Solderability 35 / 100 · Polishability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.6 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.
A8 H&T 56-58 HRC vs A8 Q&T — frequently asked
Is A8 Q&T stronger than A8 H&T 56-58 HRC?
Yes. A8 Q&T has a typical yield strength of 1,700 MPa (247 ksi) against 1,600 MPa (232 ksi) for A8 H&T 56-58 HRC — about 6% more. Tensile strength is 2,000 MPa (290 ksi) vs 1,900 MPa (276 ksi).
Which condition does FabDigit quote by default, H&T 56-58 HRC or Q&T?
Annealed is the default A8 condition in the FabDigit quote flow (neither H&T 56-58 HRC nor Q&T). 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.
When should I choose A8 H&T 56-58 HRC over A8 Q&T?
Pick A8 H&T 56-58 HRC when the part is bent, formed or impact-loaded, or when the part sees heat. Pick A8 Q&T when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in A8 H&T 56-58 HRC and A8 Q&T 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.