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Steel 25CrMoS4 +AC vs 25CrMoS4 +H

Steel · 25CrMoS4 temper comparison

25CrMoS4 +AC and 25CrMoS4 +H are two conditions of the same steel grade, 25CrMoS4: +AC (spheroidize annealed) versus +H (hardenability guaranteed). The chemistry is identical, so every difference below comes from the condition. 25CrMoS4 +H is the stronger of the two: yield strength 1,150 MPa (167 ksi) against 340 MPa (49.3 ksi) for 25CrMoS4 +AC, about 3.4 times as much; tensile strength follows at 1,450 MPa (210 ksi) vs 570 MPa (82.7 ksi). In exchange, 25CrMoS4 +AC is the more ductile: elongation 26% versus 9% for 25CrMoS4 +H, and 25CrMoS4 +H is harder (190 HB vs 170 HB).

25CrMoS4 +ACChoose it when the part is bent, formed or impact-loaded.

25CrMoS4 +HChoose it when strength drives the design.

25CrMoS4 +AC vs 25CrMoS4 +H: properties

25CrMoS4 +AC25CrMoS4 +H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

570 MPa82.7 ksi
1,450 MPa210 ksi

Yield Strength (0.2% offset)

340 MPa49.3 ksi
1,150 MPa167 ksi

Elongation at Break

26%
9%

Reduction in Area

64%
38%

Compressive Strength

350 MPa50.8 ksi
1,180 MPa171 ksi

Shear Strength

345 MPa50 ksi
870 MPa126 ksi

Fatigue Strength (Endurance Limit)

260 MPa37.7 ksi
600 MPa87 ksi

Fracture Toughness (K_IC)

125 MPa·√m114 ksi·√in
55 MPa·√m50.1 ksi·√in

Charpy V-Notch Impact (RT)

65 J47.9 ft·lbf
18 J13.3 ft·lbf

Hardness, Brinell

170 HB
190 HB

Hardness, Rockwell C

8 HRC
45 HRC

Hardness, Vickers

180 HV
446 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 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) 1,420°C2,588 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.3 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -40°C-40 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.3 % IACS
7.6 % IACS

Electrical Resistivity

2.08×10⁻⁷ Ω·m8.19 µΩ·in
2.25×10⁻⁷ Ω·m8.86 µΩ·in

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

72 / 100
67 / 100

Machinability Rating (AISI 1212 = 100 %)

80%
76%

Weldability

35 / 100
30 / 100

Formability (cold)

55 / 100
45 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 35 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2.1 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 scale25CrMoS4

25CrMoS4 +AC vs 25CrMoS4 +H — frequently asked

Is 25CrMoS4 +H stronger than 25CrMoS4 +AC?

Yes. 25CrMoS4 +H has a typical yield strength of 1,150 MPa (167 ksi) against 340 MPa (49.3 ksi) for 25CrMoS4 +AC — about 3.4 times as much. Tensile strength is 1,450 MPa (210 ksi) vs 570 MPa (82.7 ksi).

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

+QT is the default 25CrMoS4 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, 25CrMoS4 +AC or 25CrMoS4 +H?

25CrMoS4 +AC. Its machinability rates very good (72/100) against good (67/100) for 25CrMoS4 +H; for welding the order is 25CrMoS4 +AC first (fair, 35/100) then 25CrMoS4 +H (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 25CrMoS4 +AC and 25CrMoS4 +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.