Steel 18KhGT-HR vs 18KhGT-QT200
Steel · 18KhGT temper comparison
18KhGT-HR and 18KhGT-QT200 are two conditions of the same steel grade, 18KhGT: HR (hot rolled) versus QT200 (quenched (860–880 °C, oil) + tempered 200 °C). The chemistry is identical, so every difference below comes from the condition. 18KhGT-QT200 is the stronger of the two: yield strength 980 MPa (142 ksi) against 500 MPa (72.5 ksi) for 18KhGT-HR, about 96% more; tensile strength follows at 1,150 MPa (167 ksi) vs 760 MPa (110 ksi). In exchange, 18KhGT-HR is the more ductile: elongation 18% versus 11% for 18KhGT-QT200, and 18KhGT-QT200 is harder (355 HB vs 197 HB). 18KhGT-HR runs hotter in service (350°C vs 180°C continuous). On the shop floor, 18KhGT-HR machines more easily (good vs fair) and 18KhGT-HR welds better (fair vs poor).
18KhGT-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
18KhGT-QT200Choose it when strength drives the design.
18KhGT-HR vs 18KhGT-QT200: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 92 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 1,490°C2,714 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 41 W/m·K23.7 BTU/hr·ft·°F · Specific Heat Capacity 470 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 270 J/g116 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 7.8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Same in both: Formability (cold) 45 / 100 · Brazeability / Solderability 55 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 34 MJ/kg14,617 BTU/lb · Embodied Carbon (primary production) 2.3 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.
18KhGT-HR vs 18KhGT-QT200 — frequently asked
Is 18KhGT-QT200 stronger than 18KhGT-HR?
Yes. 18KhGT-QT200 has a typical yield strength of 980 MPa (142 ksi) against 500 MPa (72.5 ksi) for 18KhGT-HR — about 96% more. Tensile strength is 1,150 MPa (167 ksi) vs 760 MPa (110 ksi).
Which condition does FabDigit quote by default, HR or QT200?
HR is the default 18KhGT 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, 18KhGT-HR or 18KhGT-QT200?
18KhGT-HR. Its machinability rates good (55/100) against fair (35/100) for 18KhGT-QT200; for welding the order is 18KhGT-HR first (fair, 40/100) then 18KhGT-QT200 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 18KhGT-HR and 18KhGT-QT200 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.