Steel 20Kh-CH vs 20Kh-QT200
Steel · 20Kh temper comparison
20Kh-CH and 20Kh-QT200 are two conditions of the same steel grade, 20Kh: CH (carburized and hardened) versus QT200 (Q&T). The chemistry is identical, so every difference below comes from the condition. 20Kh-CH is the stronger of the two: tensile strength 900 MPa (131 ksi) against 850 MPa (123 ksi) for 20Kh-QT200, about 6% more. In exchange, 20Kh-QT200 is the more ductile: elongation 13% versus 10% for 20Kh-CH, and 20Kh-CH is harder (600 HB vs 255 HB). On the shop floor, 20Kh-QT200 machines more easily (fair vs not recommended) and 20Kh-QT200 welds better (fair vs poor).
20Kh-CHChoose it when strength drives the design.
20Kh-QT200Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
20Kh-CH vs 20Kh-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
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 211 GPa30.6 Msi · Shear Modulus 82 GPa11.9 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Hardness, Rockwell B 82 HRB
Physical
Density and transition temperatures.
Same in both: Density 7.82 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,460°C2,660 °F · Liquidus Temperature 1,510°C2,750 °F
Thermal
How each material carries heat and how hot it can run.
Same in both: Thermal Conductivity 43 W/m·K24.8 BTU/hr·ft·°F · Specific Heat Capacity 466 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.6 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 270 J/g116 BTU/lb · Max Service Temperature (continuous) 180°C356 °F · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 8.2 % IACS · Electrical Resistivity 2.1×10⁻⁷ Ω·m8.27 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 11 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Polishability
Same in both: Formability (cold) 65 / 100 · Castability 30 / 100 · Brazeability / Solderability 65 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 25%
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.
20Kh-CH vs 20Kh-QT200 — frequently asked
Is 20Kh-CH stronger than 20Kh-QT200?
Yes. 20Kh-CH has a typical tensile strength of 900 MPa (131 ksi) against 850 MPa (123 ksi) for 20Kh-QT200 — about 6% more.
Which condition does FabDigit quote by default, CH or QT200?
A is the default 20Kh condition in the FabDigit quote flow (neither CH nor QT200). 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, 20Kh-CH or 20Kh-QT200?
20Kh-QT200. Its machinability rates fair (42/100) against not recommended (12/100) for 20Kh-CH; for welding the order is 20Kh-QT200 first (fair, 35/100) then 20Kh-CH (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 20Kh-CH and 20Kh-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.