Steel 4Cr5MoSiV QT 40-44 HRC vs 4Cr5MoSiV QT 48-52 HRC
Steel · 4Cr5MoSiV temper comparison
4Cr5MoSiV QT 40-44 HRC and 4Cr5MoSiV QT 48-52 HRC are two conditions of the same steel grade, 4Cr5MoSiV: QT 40-44 HRC versus QT 48-52 HRC. The chemistry is identical, so every difference below comes from the condition. 4Cr5MoSiV QT 48-52 HRC is the stronger of the two: yield strength 1,520 MPa (220 ksi) against 1,150 MPa (167 ksi) for 4Cr5MoSiV QT 40-44 HRC, about 32% more; tensile strength follows at 1,800 MPa (261 ksi) vs 1,350 MPa (196 ksi). In exchange, 4Cr5MoSiV QT 40-44 HRC is the more ductile: elongation 13% versus 9% for 4Cr5MoSiV QT 48-52 HRC, and 4Cr5MoSiV QT 48-52 HRC is harder (513 HV vs 412 HV). 4Cr5MoSiV QT 40-44 HRC runs hotter in service (560°C vs 500°C continuous). On the shop floor, 4Cr5MoSiV QT 40-44 HRC machines more easily (30 vs 15 out of 100).
4Cr5MoSiV QT 40-44 HRCChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
4Cr5MoSiV QT 48-52 HRCChoose it when strength drives the design.
4Cr5MoSiV QT 40-44 HRC vs 4Cr5MoSiV QT 48-52 HRC: 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.
4Cr5MoSiV QT 40-44 HRC4Cr5MoSiV QT 48-52 HRC
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)
Charpy V-Notch Impact (RT)
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 168 GPa24.4 Msi · Poisson's Ratio 0.3 · Hardness, Brinell 210 HB · Hardness, Rockwell B 95 HRB
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 1,480°C2,696 °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) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 3.3 % IACS · Electrical Resistivity 5.2×10⁻⁷ Ω·m20.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.55 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 %)
Same in both: Weldability 35 / 100 · Formability (cold) 25 / 100 · Castability 30 / 100 · Brazeability / Solderability 40 / 100 · Polishability 78 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.5 kg CO₂/kg · Embodied Water 70 L/kg8.4 gal/lb · Typical Recycled Content 45%
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.
4Cr5MoSiV QT 40-44 HRC vs 4Cr5MoSiV QT 48-52 HRC — frequently asked
Is 4Cr5MoSiV QT 48-52 HRC stronger than 4Cr5MoSiV QT 40-44 HRC?
Yes. 4Cr5MoSiV QT 48-52 HRC has a typical yield strength of 1,520 MPa (220 ksi) against 1,150 MPa (167 ksi) for 4Cr5MoSiV QT 40-44 HRC — about 32% more. Tensile strength is 1,800 MPa (261 ksi) vs 1,350 MPa (196 ksi).
Which condition does FabDigit quote by default, QT 40-44 HRC or QT 48-52 HRC?
Annealed is the default 4Cr5MoSiV condition in the FabDigit quote flow (neither QT 40-44 HRC nor QT 48-52 HRC). 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, 4Cr5MoSiV QT 40-44 HRC or 4Cr5MoSiV QT 48-52 HRC?
4Cr5MoSiV QT 40-44 HRC, by a small margin. Both rate poor for machinability — 30/100 against 15/100 for 4Cr5MoSiV QT 48-52 HRC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4Cr5MoSiV QT 40-44 HRC and 4Cr5MoSiV QT 48-52 HRC 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.