Steel 45SiCrV6-2 +A vs 45SiCrV6-2 +QT
Steel · 45SiCrV6-2 temper comparison
45SiCrV6-2 +A and 45SiCrV6-2 +QT are two conditions of the same steel grade, 45SiCrV6-2: +A (annealed) versus +QT (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. 45SiCrV6-2 +QT is the stronger of the two: yield strength 1,500 MPa (218 ksi) against 450 MPa (65.3 ksi) for 45SiCrV6-2 +A, about 3.3 times as much; tensile strength follows at 1,700 MPa (247 ksi) vs 750 MPa (109 ksi). In exchange, 45SiCrV6-2 +A is the more ductile: elongation 15% versus 7% for 45SiCrV6-2 +QT, and 45SiCrV6-2 +QT is harder (490 HB vs 225 HB). 45SiCrV6-2 +A runs hotter in service (300°C vs 250°C continuous). On the shop floor, 45SiCrV6-2 +A machines more easily (good vs poor) and 45SiCrV6-2 +A welds better (25 vs 15 out of 100).
45SiCrV6-2 +AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
45SiCrV6-2 +QTChoose it when strength drives the design.
45SiCrV6-2 +A vs 45SiCrV6-2 +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
Reduction in Area
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 206 GPa29.9 Msi · Shear Modulus 79.5 GPa11.5 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 1,550 MPa225 ksi · Shear Strength 1,020 MPa148 ksi · Fracture Toughness (K_IC) 50 MPa·√m45.5 ksi·√in · Hardness, Rockwell C 50 HRC
Physical
Density and transition temperatures.
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7 % IACS · Electrical Resistivity 2.5×10⁻⁷ Ω·m9.84 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 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: Brazeability / Solderability 35 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.1 kg CO₂/kg · Embodied Water 50 L/kg6 gal/lb · Typical Recycled Content 30%
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.
45SiCrV6-2 +A vs 45SiCrV6-2 +QT — frequently asked
Is 45SiCrV6-2 +QT stronger than 45SiCrV6-2 +A?
Yes. 45SiCrV6-2 +QT has a typical yield strength of 1,500 MPa (218 ksi) against 450 MPa (65.3 ksi) for 45SiCrV6-2 +A — about 3.3 times as much. Tensile strength is 1,700 MPa (247 ksi) vs 750 MPa (109 ksi).
Which condition does FabDigit quote by default, +A or +QT?
+QT is the default 45SiCrV6-2 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, 45SiCrV6-2 +A or 45SiCrV6-2 +QT?
45SiCrV6-2 +A. Its machinability rates good (55/100) against poor (28/100) for 45SiCrV6-2 +QT; for welding the order is 45SiCrV6-2 +A first (poor, 25/100) then 45SiCrV6-2 +QT (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 45SiCrV6-2 +A and 45SiCrV6-2 +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.