Steel 20MnMoNi4-5-A vs 20MnMoNi4-5-QT
Steel · 20MnMoNi4-5 temper comparison
20MnMoNi4-5-A and 20MnMoNi4-5-QT are two conditions of the same steel grade, 20MnMoNi4-5: A (solution annealed) versus QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 20MnMoNi4-5-QT is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 330 MPa (47.9 ksi) for 20MnMoNi4-5-A, about 42% more; tensile strength follows at 640 MPa (92.8 ksi) vs 540 MPa (78.3 ksi). In exchange, 20MnMoNi4-5-A is the more ductile: elongation 27% versus 23% for 20MnMoNi4-5-QT, and 20MnMoNi4-5-QT is harder (200 HB vs 160 HB).
20MnMoNi4-5-AChoose it when the part is bent, formed or impact-loaded.
20MnMoNi4-5-QTChoose it when strength drives the design.
20MnMoNi4-5-A vs 20MnMoNi4-5-QT: 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
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 166 GPa24.1 Msi · Poisson's Ratio 0.29 · Reduction in Area 65% · Compressive Strength 470 MPa68.2 ksi · Shear Strength 400 MPa58 ksi · Fracture Toughness (K_IC) 200 MPa·√m182 ksi·√in · Hardness, Rockwell B 94 HRB · Hardness, Vickers 210 HV
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,450°C2,642 °F · Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 41 W/m·K23.7 BTU/hr·ft·°F · Specific Heat Capacity 460 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 · Max Service Temperature (continuous) 371°C700 °F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.62 V · Corrosion Resistance 14 / 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 65 / 100 · Castability 30 / 100 · Brazeability / Solderability 40 / 100 · Polishability 55 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 50 L/kg6 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.
20MnMoNi4-5-A vs 20MnMoNi4-5-QT — frequently asked
Is 20MnMoNi4-5-QT stronger than 20MnMoNi4-5-A?
Yes. 20MnMoNi4-5-QT has a typical yield strength of 470 MPa (68.2 ksi) against 330 MPa (47.9 ksi) for 20MnMoNi4-5-A — about 42% more. Tensile strength is 640 MPa (92.8 ksi) vs 540 MPa (78.3 ksi).
Which condition does FabDigit quote by default, A or QT?
QT is the default 20MnMoNi4-5 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, 20MnMoNi4-5-A or 20MnMoNi4-5-QT?
20MnMoNi4-5-A, by a small margin. Both rate good for machinability — 62/100 against 55/100 for 20MnMoNi4-5-QT.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 20MnMoNi4-5-A and 20MnMoNi4-5-QT 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.