Steel 30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT400
Steel · 30CrMnSiNi2A temper comparison
30CrMnSiNi2A-QT200 and 30CrMnSiNi2A-QT400 are two conditions of the same steel grade, 30CrMnSiNi2A: QT200 (Q&T 200 °C) versus QT400 (Q&T 400 °C). The chemistry is identical, so every difference below comes from the condition. 30CrMnSiNi2A-QT200 is the stronger of the two: yield strength 1,550 MPa (225 ksi) against 1,350 MPa (196 ksi) for 30CrMnSiNi2A-QT400, about 15% more; tensile strength follows at 1,820 MPa (264 ksi) vs 1,500 MPa (218 ksi). In exchange, 30CrMnSiNi2A-QT400 is the more ductile: elongation 12% versus 10% for 30CrMnSiNi2A-QT200, and 30CrMnSiNi2A-QT200 is harder (51 HRC vs 44 HRC). 30CrMnSiNi2A-QT400 runs hotter in service (350°C vs 150°C continuous).
30CrMnSiNi2A-QT200Choose it when strength drives the design.
30CrMnSiNi2A-QT400Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT400: 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.
30CrMnSiNi2A-QT20030CrMnSiNi2A-QT400
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, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 78 GPa11.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3
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.
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) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -60°C-76 °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) -0.6 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 %)
Formability (cold)
Same in both: Weldability 20 / 100 · Brazeability / Solderability 30 / 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) 2.5 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 20%
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.
30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT400 — frequently asked
Is 30CrMnSiNi2A-QT200 stronger than 30CrMnSiNi2A-QT400?
Yes. 30CrMnSiNi2A-QT200 has a typical yield strength of 1,550 MPa (225 ksi) against 1,350 MPa (196 ksi) for 30CrMnSiNi2A-QT400 — about 15% more. Tensile strength is 1,820 MPa (264 ksi) vs 1,500 MPa (218 ksi).
Which condition does FabDigit quote by default, QT200 or QT400?
QT260 is the default 30CrMnSiNi2A condition in the FabDigit quote flow (neither QT200 nor QT400). 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, 30CrMnSiNi2A-QT200 or 30CrMnSiNi2A-QT400?
30CrMnSiNi2A-QT400, by a small margin. Both rate poor for machinability — 26/100 against 18/100 for 30CrMnSiNi2A-QT200.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 30CrMnSiNi2A-QT200 and 30CrMnSiNi2A-QT400 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.