Steel 30CrNiMo8 Q&T vs 30CrNiMo8 Q&T 40-44 HRC
Steel · 30CrNiMo8 temper comparison
30CrNiMo8 Q&T and 30CrNiMo8 Q&T 40-44 HRC are two conditions of the same steel grade, 30CrNiMo8: Q&T (quenched and tempered) versus Q&T 40-44 HRC (Q&T to 40–44 HRC). The chemistry is identical, so every difference below comes from the condition. 30CrNiMo8 Q&T 40-44 HRC is the stronger of the two: yield strength 1,220 MPa (177 ksi) against 1,000 MPa (145 ksi) for 30CrNiMo8 Q&T, about 22% more; tensile strength follows at 1,400 MPa (203 ksi) vs 1,200 MPa (174 ksi). In exchange, 30CrNiMo8 Q&T is the more ductile: elongation 12% versus 9% for 30CrNiMo8 Q&T 40-44 HRC, and 30CrNiMo8 Q&T 40-44 HRC is harder (400 HB vs 355 HB). On the shop floor, 30CrNiMo8 Q&T machines more easily (fair vs poor).
30CrNiMo8 Q&TChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
30CrNiMo8 Q&T 40-44 HRCChoose it when strength drives the design.
30CrNiMo8 Q&T vs 30CrNiMo8 Q&T 40-44 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.
30CrNiMo8 Q&T30CrNiMo8 Q&T 40-44 HRC
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)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 1,050 MPa152 ksi · Shear Strength 720 MPa104 ksi
Physical
Density and transition temperatures.
Same in both: Density 7.85 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.
Same in both: Thermal Conductivity 34 W/m·K19.6 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 250 J/g107 BTU/lb · Max Service Temperature (continuous) 350°C662 °F · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.5 % IACS · Electrical Resistivity 2.3×10⁻⁷ Ω·m9.06 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.61 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 %)
Same in both: Weldability 22 / 100 · Formability (cold) 18 / 100 · Brazeability / Solderability 45 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.4 kg CO₂/kg · Embodied Water 55 L/kg6.6 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.
30CrNiMo8 Q&T vs 30CrNiMo8 Q&T 40-44 HRC — frequently asked
Is 30CrNiMo8 Q&T 40-44 HRC stronger than 30CrNiMo8 Q&T?
Yes. 30CrNiMo8 Q&T 40-44 HRC has a typical yield strength of 1,220 MPa (177 ksi) against 1,000 MPa (145 ksi) for 30CrNiMo8 Q&T — about 22% more. Tensile strength is 1,400 MPa (203 ksi) vs 1,200 MPa (174 ksi).
Which condition does FabDigit quote by default, Q&T or Q&T 40-44 HRC?
Q&T is the default 30CrNiMo8 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, 30CrNiMo8 Q&T or 30CrNiMo8 Q&T 40-44 HRC?
30CrNiMo8 Q&T. Its machinability rates fair (38/100) against poor (26/100) for 30CrNiMo8 Q&T 40-44 HRC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 30CrNiMo8 Q&T and 30CrNiMo8 Q&T 40-44 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.