Steel 30NiCrMo16-A vs 30NiCrMo16-QT1800
Steel · 30NiCrMo16 temper comparison
30NiCrMo16-A and 30NiCrMo16-QT1800 are two conditions of the same steel grade, 30NiCrMo16: A (solution annealed) versus QT1800 (Q&T 1790–1930 MPa). The chemistry is identical, so every difference below comes from the condition. 30NiCrMo16-QT1800 is the stronger of the two: yield strength 1,620 MPa (235 ksi) against 550 MPa (79.8 ksi) for 30NiCrMo16-A, about 195% more; tensile strength follows at 1,860 MPa (270 ksi) vs 820 MPa (119 ksi). In exchange, 30NiCrMo16-A is the more ductile: elongation 18% versus 12% for 30NiCrMo16-QT1800, and 30NiCrMo16-QT1800 is harder (520 HB vs 230 HB). 30NiCrMo16-A runs hotter in service (400°C vs 200°C continuous). On the shop floor, 30NiCrMo16-A machines more easily (fair vs poor) and 30NiCrMo16-A welds better (30 vs 15 out of 100).
30NiCrMo16-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
30NiCrMo16-QT1800Choose it when strength drives the design.
30NiCrMo16-A vs 30NiCrMo16-QT1800: 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, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Compressive Strength 1,680 MPa244 ksi · Shear Strength 1,120 MPa162 ksi · Fracture Toughness (K_IC) 80 MPa·√m72.8 ksi·√in
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 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 33 W/m·K19.1 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.8 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -70°C-94 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 6.8 % 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 14 / 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 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 36 MJ/kg15,477 BTU/lb · Embodied Carbon (primary production) 2.6 kg CO₂/kg · Embodied Water 60 L/kg7.2 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.
30NiCrMo16-A vs 30NiCrMo16-QT1800 — frequently asked
Is 30NiCrMo16-QT1800 stronger than 30NiCrMo16-A?
Yes. 30NiCrMo16-QT1800 has a typical yield strength of 1,620 MPa (235 ksi) against 550 MPa (79.8 ksi) for 30NiCrMo16-A — about 195% more. Tensile strength is 1,860 MPa (270 ksi) vs 820 MPa (119 ksi).
Which condition does FabDigit quote by default, A or QT1800?
QT1800 is the default 30NiCrMo16 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, 30NiCrMo16-A or 30NiCrMo16-QT1800?
30NiCrMo16-A. Its machinability rates fair (45/100) against poor (15/100) for 30NiCrMo16-QT1800; for welding the order is 30NiCrMo16-A first (poor, 30/100) then 30NiCrMo16-QT1800 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 30NiCrMo16-A and 30NiCrMo16-QT1800 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.