Steel SCM822-A vs SCM822-CH
Steel · SCM822 temper comparison
SCM822-A and SCM822-CH are two conditions of the same steel grade, SCM822: A (solution annealed) versus CH (carburized and hardened). The chemistry is identical, so every difference below comes from the condition. SCM822-CH is the stronger of the two: yield strength 1,000 MPa (145 ksi) against 460 MPa (66.7 ksi) for SCM822-A, about 117% more; tensile strength follows at 1,250 MPa (181 ksi) vs 720 MPa (104 ksi). In exchange, SCM822-A is the more ductile: elongation 21% versus 11% for SCM822-CH, and SCM822-CH is harder (60 HRC vs 14 HRC). SCM822-A runs hotter in service (350°C vs 180°C continuous). On the shop floor, SCM822-A machines more easily (good vs not recommended) and SCM822-A welds better (poor vs not recommended).
SCM822-AChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
SCM822-CHChoose it when strength drives the design.
SCM822-A vs SCM822-CH: 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
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 206 GPa29.9 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Shear Strength 435 MPa63.1 ksi · Hardness, Brinell 200 HB · Hardness, Rockwell B 93 HRB
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 1,500°C2,732 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 42 W/m·K24.3 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 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) -0.61 V · Corrosion Resistance 10 / 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) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.2 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.
SCM822-A vs SCM822-CH — frequently asked
Is SCM822-CH stronger than SCM822-A?
Yes. SCM822-CH has a typical yield strength of 1,000 MPa (145 ksi) against 460 MPa (66.7 ksi) for SCM822-A — about 117% more. Tensile strength is 1,250 MPa (181 ksi) vs 720 MPa (104 ksi).
Which condition does FabDigit quote by default, A or CH?
A is the default SCM822 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, SCM822-A or SCM822-CH?
SCM822-A. Its machinability rates good (55/100) against not recommended (10/100) for SCM822-CH; for welding the order is SCM822-A first (poor, 30/100) then SCM822-CH (not recommended, 5/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in SCM822-A and SCM822-CH 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.