Steel 100CrMnSi6-4 +AR vs 100CrMnSi6-4 BG (bainite hardened)
Steel · 100CrMnSi6-4 temper comparison
100CrMnSi6-4 +AR and 100CrMnSi6-4 BG (bainite hardened) are two conditions of the same steel grade, 100CrMnSi6-4: +AR (hot rolled) versus BG (bainite hardened) (bainite hardened). The chemistry is identical, so every difference below comes from the condition. 100CrMnSi6-4 BG (bainite hardened) is the stronger of the two: yield strength 1,750 MPa (254 ksi) against 520 MPa (75.4 ksi) for 100CrMnSi6-4 +AR, about 3.4 times as much; tensile strength follows at 2,050 MPa (297 ksi) vs 950 MPa (138 ksi). In exchange, 100CrMnSi6-4 +AR is the more ductile: elongation 12% versus 3% for 100CrMnSi6-4 BG (bainite hardened), and 100CrMnSi6-4 +AR is harder (280 HB vs 195 HB). 100CrMnSi6-4 +AR runs hotter in service (200°C vs 180°C continuous). On the shop floor, 100CrMnSi6-4 +AR machines more easily (poor vs not recommended).
100CrMnSi6-4 +ARChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
100CrMnSi6-4 BG (bainite hardened)Choose it when strength drives the design.
100CrMnSi6-4 +AR vs 100CrMnSi6-4 BG (bainite hardened): 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.
100CrMnSi6-4 +AR100CrMnSi6-4 BG (bainite hardened)
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)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 166 GPa24.1 Msi · Poisson's Ratio 0.29 · Charpy V-Notch Impact (RT) 10 J7.4 ft·lbf
Physical
Density and transition temperatures.
Same in both: Density 7.81 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 460 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 250 J/g107 BTU/lb · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Same in both: Electrical Conductivity 7 % IACS
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
Formability (cold)
Same in both: Brazeability / Solderability 40 / 100 · Polishability 85 / 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.
100CrMnSi6-4 +AR vs 100CrMnSi6-4 BG (bainite hardened) — frequently asked
Is 100CrMnSi6-4 BG (bainite hardened) stronger than 100CrMnSi6-4 +AR?
Yes. 100CrMnSi6-4 BG (bainite hardened) has a typical yield strength of 1,750 MPa (254 ksi) against 520 MPa (75.4 ksi) for 100CrMnSi6-4 +AR — about 3.4 times as much. Tensile strength is 2,050 MPa (297 ksi) vs 950 MPa (138 ksi).
Which condition does FabDigit quote by default, +AR or BG (bainite hardened)?
+AC is the default 100CrMnSi6-4 condition in the FabDigit quote flow (neither +AR nor BG (bainite hardened)). 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, 100CrMnSi6-4 +AR or 100CrMnSi6-4 BG (bainite hardened)?
100CrMnSi6-4 +AR. Its machinability rates poor (30/100) against not recommended (9/100) for 100CrMnSi6-4 BG (bainite hardened).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 100CrMnSi6-4 +AR and 100CrMnSi6-4 BG (bainite hardened) 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.