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Steel 1108-A vs 1108-HR

Steel · 1108 temper comparison

1108-A and 1108-HR are two conditions of the same steel grade, 1108: A (solution annealed) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. 1108-HR is the stronger of the two: yield strength 190 MPa (27.6 ksi) against 180 MPa (26.1 ksi) for 1108-A, about 6% more. 1108-HR is harder — 95 HB against 90 HB for 1108-A — which matters for wear surfaces and threads. On the shop floor, 1108-A forms better (very good vs good).

1108-HRChoose it when strength drives the design, or when surface hardness matters.

1108-A vs 1108-HR: properties

1108-A1108-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

325 MPa47.1 ksi
340 MPa49.3 ksi

Yield Strength (0.2% offset)

180 MPa26.1 ksi
190 MPa27.6 ksi

Elongation at Break

33%
30%

Reduction in Area

55%
50%

Compressive Strength

180 MPa26.1 ksi
190 MPa27.6 ksi

Shear Strength

215 MPa31.2 ksi
220 MPa31.9 ksi

Fatigue Strength (Endurance Limit)

160 MPa23.2 ksi
170 MPa24.7 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

90 HB
95 HB

Hardness, Rockwell B

50 HRB
55 HRB

Same in both: Elastic (Young's) Modulus 200 GPa29 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) 1,425°C2,597 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

52 W/m·K30 BTU/hr·ft·°F
51 W/m·K29.5 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 472 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.9 µm/m·K6.6 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10.8 % IACS
10.5 % IACS

Same in both: Electrical Resistivity 1.6×10⁻⁷ Ω·m6.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 8 / 100

Manufacturability

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

Machinability

64 / 100
70 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
70%

Weldability

55 / 100
52 / 100

Formability (cold)

75 / 100
65 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 65 / 100 · Polishability 45 / 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 45 L/kg5.4 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 scale1108

1108-A vs 1108-HR — frequently asked

Is 1108-HR stronger than 1108-A?

Yes. 1108-HR has a typical yield strength of 190 MPa (27.6 ksi) against 180 MPa (26.1 ksi) for 1108-A — about 6% more. Tensile strength is 340 MPa (49.3 ksi) vs 325 MPa (47.1 ksi).

Which condition does FabDigit quote by default, A or HR?

CD is the default 1108 condition in the FabDigit quote flow (neither A nor HR). 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, 1108-A or 1108-HR?

1108-HR. Its machinability rates very good (70/100) against good (64/100) for 1108-A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1108-A and 1108-HR 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.