FabDigitFabDigit

Steel 30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT300

Steel · 30CrMnSiNi2A temper comparison

30CrMnSiNi2A-QT200 and 30CrMnSiNi2A-QT300 are two conditions of the same steel grade, 30CrMnSiNi2A: QT200 (Q&T 200 °C) versus QT300 (Q&T 300 °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 1,400 MPa (203 ksi) for 30CrMnSiNi2A-QT300, about 11% more; tensile strength follows at 1,820 MPa (264 ksi) vs 1,630 MPa (236 ksi). In exchange, 30CrMnSiNi2A-QT300 is the more ductile: elongation 13% versus 10% for 30CrMnSiNi2A-QT200, and 30CrMnSiNi2A-QT200 is harder (51 HRC vs 46 HRC). 30CrMnSiNi2A-QT300 runs hotter in service (280°C vs 150°C continuous).

30CrMnSiNi2A-QT200Choose it when strength drives the design.

30CrMnSiNi2A-QT300Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT300: properties

30CrMnSiNi2A-QT20030CrMnSiNi2A-QT300

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

1,820 MPa264 ksi
1,630 MPa236 ksi

Yield Strength (0.2% offset)

1,550 MPa225 ksi
1,400 MPa203 ksi

Elongation at Break

10%
13%

Reduction in Area

45%
53%

Shear Strength

1,090 MPa158 ksi
1,020 MPa148 ksi

Fatigue Strength (Endurance Limit)

850 MPa123 ksi
780 MPa113 ksi

Fracture Toughness (K_IC)

52 MPa·√m47.3 ksi·√in
72 MPa·√m65.5 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
50 J36.9 ft·lbf

Hardness, Rockwell C

51 HRC
46 HRC

Hardness, Vickers

545 HV
460 HV

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 · Compressive Strength 1,550 MPa225 ksi

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)

150°C302 °F
280°C536 °F

Same in both: Thermal Conductivity 31 W/m·K17.9 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 -60°C-76 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 5.7 % IACS · Electrical Resistivity 3×10⁻⁷ Ω·m11.8 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

18 / 100
24 / 100

Machinability Rating (AISI 1212 = 100 %)

15%
22%

Same in both: Weldability 20 / 100 · Formability (cold) 10 / 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale30CrMnSiNi2A

30CrMnSiNi2A-QT200 vs 30CrMnSiNi2A-QT300 — frequently asked

Is 30CrMnSiNi2A-QT200 stronger than 30CrMnSiNi2A-QT300?

Yes. 30CrMnSiNi2A-QT200 has a typical yield strength of 1,550 MPa (225 ksi) against 1,400 MPa (203 ksi) for 30CrMnSiNi2A-QT300 — about 11% more. Tensile strength is 1,820 MPa (264 ksi) vs 1,630 MPa (236 ksi).

Which condition does FabDigit quote by default, QT200 or QT300?

QT260 is the default 30CrMnSiNi2A condition in the FabDigit quote flow (neither QT200 nor QT300). 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-QT300?

30CrMnSiNi2A-QT300, by a small margin. Both rate poor for machinability — 24/100 against 18/100 for 30CrMnSiNi2A-QT200.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 30CrMnSiNi2A-QT200 and 30CrMnSiNi2A-QT300 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.