Steel M34-A vs M34 HT-67
Steel · M34 temper comparison
M34-A and M34 HT-67 are two conditions of the same steel grade, M34: A (solution annealed) versus HT-67 (HT 66–68 HRC). The chemistry is identical, so every difference below comes from the condition. M34 HT-67 is the stronger of the two: yield strength 2,150 MPa (312 ksi) against 560 MPa (81.2 ksi) for M34-A, about 3.8 times as much; tensile strength follows at 2,400 MPa (348 ksi) vs 880 MPa (128 ksi). In exchange, M34-A is the more ductile: elongation 22% versus 0% for M34 HT-67, and M34 HT-67 is harder (925 HV vs 250 HV). M34 HT-67 runs hotter in service (620°C vs 550°C continuous). On the shop floor, M34-A machines more easily (fair vs not recommended) and M34-A welds better (poor vs not recommended).
M34-AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
M34 HT-67Choose it when strength drives the design, or when the part sees heat.
M34-A vs M34 HT-67: 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.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Vickers
Same in both: Shear Modulus 84 GPa12.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Brinell 235 HB · Hardness, Rockwell B 99 HRB
Physical
Density and transition temperatures.
Same in both: Density 8.03 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,240°C2,264 °F · Liquidus Temperature 1,425°C2,597 °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 420 J/kg·K0.1 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 10.7 µm/m·K5.9 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -100°C-148 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 25 / 100 · Brazeability / Solderability 55 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 78 MJ/kg33,534 BTU/lb · Embodied Carbon (primary production) 5.6 kg CO₂/kg · Embodied Water 110 L/kg13.2 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.
M34-A vs M34 HT-67 — frequently asked
Is M34 HT-67 stronger than M34-A?
Yes. M34 HT-67 has a typical yield strength of 2,150 MPa (312 ksi) against 560 MPa (81.2 ksi) for M34-A — about 3.8 times as much. Tensile strength is 2,400 MPa (348 ksi) vs 880 MPa (128 ksi).
Which condition does FabDigit quote by default, A or HT-67?
A is the default M34 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, M34-A or M34 HT-67?
M34-A. Its machinability rates fair (35/100) against not recommended (6/100) for M34 HT-67; for welding the order is M34-A first (poor, 15/100) then M34 HT-67 (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in M34-A and M34 HT-67 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.