Steel EM12K-AW vs EM12K PWHT
Steel · EM12K temper comparison
EM12K-AW and EM12K PWHT are two conditions of the same steel grade, EM12K: AW (as-welded deposit) versus PWHT (post-weld heat treated). The chemistry is identical, so every difference below comes from the condition. EM12K-AW is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 420 MPa (60.9 ksi) for EM12K PWHT, about 7% more; tensile strength follows at 550 MPa (79.8 ksi) vs 520 MPa (75.4 ksi). EM12K-AW is harder — 165 HB against 155 HB for EM12K PWHT — which matters for wear surfaces and threads.
EM12K-AWChoose it when strength drives the design, or when surface hardness matters.
EM12K-AW vs EM12K PWHT: 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, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,500°C2,732 °F · Liquidus Temperature 1,520°C2,768 °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 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Min Service Temperature -30°C-22 °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) -0.62 V · Corrosion Resistance 10 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 95 / 100 · Brazeability / Solderability 75 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 25%
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.
EM12K-AW vs EM12K PWHT — frequently asked
Is EM12K-AW stronger than EM12K PWHT?
Yes. EM12K-AW has a typical yield strength of 450 MPa (65.3 ksi) against 420 MPa (60.9 ksi) for EM12K PWHT — about 7% more. Tensile strength is 550 MPa (79.8 ksi) vs 520 MPa (75.4 ksi).
Which condition does FabDigit quote by default, AW or PWHT?
AW is the default EM12K 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, EM12K-AW or EM12K PWHT?
EM12K PWHT. Its machinability rates very good (70/100) against good (65/100) for EM12K-AW.
Ready to make it?
Upload a CAD file and FabDigit prices the part in EM12K-AW and EM12K PWHT 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.