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Steel 30MoB1 +AC vs 30MoB1 +H

Steel · 30MoB1 temper comparison

30MoB1 +AC and 30MoB1 +H are two conditions of the same steel grade, 30MoB1: +AC (spheroidize annealed) versus +H (guaranteed hardenability, supplied/used in the hardened (quenched +…). The chemistry is identical, so every difference below comes from the condition. 30MoB1 +H is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 320 MPa (46.4 ksi) for 30MoB1 +AC, about 3.9 times as much; tensile strength follows at 1,550 MPa (225 ksi) vs 520 MPa (75.4 ksi). In exchange, 30MoB1 +AC is the more ductile: elongation 23% versus 8% for 30MoB1 +H, and 30MoB1 +H is harder (430 HB vs 152 HB). 30MoB1 +AC runs hotter in service (400°C vs 180°C continuous). On the shop floor, 30MoB1 +AC machines more easily (fair vs poor) and 30MoB1 +AC welds better (good vs poor).

30MoB1 +ACChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

30MoB1 +HChoose it when strength drives the design.

30MoB1 +AC vs 30MoB1 +H: properties

30MoB1 +AC30MoB1 +H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

520 MPa75.4 ksi
1,550 MPa225 ksi

Yield Strength (0.2% offset)

320 MPa46.4 ksi
1,250 MPa181 ksi

Elongation at Break

23%
8%

Reduction in Area

66%
35%

Compressive Strength

330 MPa47.9 ksi
540 MPa78.3 ksi

Shear Strength

320 MPa46.4 ksi
930 MPa135 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
600 MPa87 ksi

Charpy V-Notch Impact (RT)

85 J62.7 ft·lbf
20 J14.8 ft·lbf

Hardness, Brinell

152 HB
430 HB

Hardness, Rockwell B

80 HRB
90 HRB

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

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,430°C2,606 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

How each material carries heat and how hot it can run.

Max Service Temperature (continuous)

400°C752 °F
180°C356 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 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 270 J/g116 BTU/lb · Min Service Temperature -30°C-22 °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 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

52 / 100
25 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
30%

Weldability

55 / 100
25 / 100

Formability (cold)

90 / 100
5 / 100

Same in both: Brazeability / Solderability 60 / 100 · Polishability 55 / 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 55 L/kg6.6 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 scale30MoB1

30MoB1 +AC vs 30MoB1 +H — frequently asked

Is 30MoB1 +H stronger than 30MoB1 +AC?

Yes. 30MoB1 +H has a typical yield strength of 1,250 MPa (181 ksi) against 320 MPa (46.4 ksi) for 30MoB1 +AC — about 3.9 times as much. Tensile strength is 1,550 MPa (225 ksi) vs 520 MPa (75.4 ksi).

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

+AC+C is the default 30MoB1 condition in the FabDigit quote flow (neither +AC nor +H). 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, 30MoB1 +AC or 30MoB1 +H?

30MoB1 +AC. Its machinability rates fair (52/100) against poor (25/100) for 30MoB1 +H; for welding the order is 30MoB1 +AC first (good, 55/100) then 30MoB1 +H (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 30MoB1 +AC and 30MoB1 +H 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.