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Steel 100CrMnSi6-4 +AC vs 100CrMnSi6-4 +AR

Steel · 100CrMnSi6-4 temper comparison

100CrMnSi6-4 +AC and 100CrMnSi6-4 +AR are two conditions of the same steel grade, 100CrMnSi6-4: +AC (spheroidize annealed) versus +AR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 100CrMnSi6-4 +AR is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 430 MPa (62.4 ksi) for 100CrMnSi6-4 +AC, about 21% more; tensile strength follows at 950 MPa (138 ksi) vs 700 MPa (102 ksi). In exchange, 100CrMnSi6-4 +AC is the more ductile: elongation 18% versus 12% for 100CrMnSi6-4 +AR, and 100CrMnSi6-4 +AR is harder (280 HB vs 195 HB). On the shop floor, 100CrMnSi6-4 +AC machines more easily (fair vs poor).

100CrMnSi6-4 +ACChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

100CrMnSi6-4 +ARChoose it when strength drives the design.

100CrMnSi6-4 +AC vs 100CrMnSi6-4 +AR: properties

100CrMnSi6-4 +AC100CrMnSi6-4 +AR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

700 MPa102 ksi
950 MPa138 ksi

Yield Strength (0.2% offset)

430 MPa62.4 ksi
520 MPa75.4 ksi

Elongation at Break

18%
12%

Reduction in Area

40%
25%

Compressive Strength

450 MPa65.3 ksi
560 MPa81.2 ksi

Shear Strength

470 MPa68.2 ksi
600 MPa87 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
420 MPa60.9 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
10 J7.4 ft·lbf

Hardness, Brinell

195 HB
280 HB

Hardness, Rockwell B

92 HRB
105 HRB

Hardness, Vickers

205 HV
295 HV

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

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

43 W/m·K24.8 BTU/hr·ft·°F
41 W/m·K23.7 BTU/hr·ft·°F

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 · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

2.5×10⁻⁷ Ω·m9.84 µΩ·in
2.6×10⁻⁷ Ω·m10.2 µΩ·in

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

45 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
25%

Weldability

10 / 100
8 / 100

Formability (cold)

35 / 100
15 / 100

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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale100CrMnSi6-4

100CrMnSi6-4 +AC vs 100CrMnSi6-4 +AR — frequently asked

Is 100CrMnSi6-4 +AR stronger than 100CrMnSi6-4 +AC?

Yes. 100CrMnSi6-4 +AR has a typical yield strength of 520 MPa (75.4 ksi) against 430 MPa (62.4 ksi) for 100CrMnSi6-4 +AC — about 21% more. Tensile strength is 950 MPa (138 ksi) vs 700 MPa (102 ksi).

Which condition does FabDigit quote by default, +AC or +AR?

+AC is the default 100CrMnSi6-4 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, 100CrMnSi6-4 +AC or 100CrMnSi6-4 +AR?

100CrMnSi6-4 +AC. Its machinability rates fair (45/100) against poor (30/100) for 100CrMnSi6-4 +AR.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 100CrMnSi6-4 +AC and 100CrMnSi6-4 +AR 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.