FabDigitFabDigit

Steel A204-HR vs A204 Q&T

Steel · A204 temper comparison

A204-HR and A204 Q&T are two conditions of the same steel grade, A204: HR (hot rolled) versus Q&T (quenched and tempered). The chemistry is identical, so every difference below comes from the condition. A204 Q&T is the stronger of the two: yield strength 405 MPa (58.7 ksi) against 315 MPa (45.7 ksi) for A204-HR, about 29% more; tensile strength follows at 570 MPa (82.7 ksi) vs 520 MPa (75.4 ksi). A204 Q&T is harder — 180 HB against 160 HB for A204-HR — which matters for wear surfaces and threads.

A204 Q&TChoose it when strength drives the design, or when surface hardness matters.

A204-HR vs A204 Q&T: properties

A204-HRA204 Q&T

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

520 MPa75.4 ksi
570 MPa82.7 ksi

Yield Strength (0.2% offset)

315 MPa45.7 ksi
405 MPa58.7 ksi

Elongation at Break

24%
22%

Reduction in Area

48%
58%

Compressive Strength

315 MPa45.7 ksi
405 MPa58.7 ksi

Shear Strength

320 MPa46.4 ksi
350 MPa50.8 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

85 MPa·√m77.4 ksi·√in
120 MPa·√m109 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
75 J55.3 ft·lbf

Hardness, Brinell

160 HB
180 HB

Hardness, Rockwell B

84 HRB
89 HRB

Hardness, Vickers

168 HV
190 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 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) 1,460°C2,660 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

44 W/m·K25.4 BTU/hr·ft·°F
43 W/m·K24.8 BTU/hr·ft·°F

Max Service Temperature (continuous)

480°C896 °F
455°C851 °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 · Min Service Temperature -29°C-20 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8.2 % IACS
8 % IACS

Electrical Resistivity

2.1×10⁻⁷ Ω·m8.27 µΩ·in
2.15×10⁻⁷ Ω·m8.46 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

58 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
52%

Weldability

70 / 100
65 / 100

Formability (cold)

60 / 100
52 / 100

Same in both: Castability 40 / 100 · Brazeability / Solderability 55 / 100 · Polishability 50 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 55 L/kg6.6 gal/lb · Typical Recycled Content 25%

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 scaleA204

A204-HR vs A204 Q&T — frequently asked

Is A204 Q&T stronger than A204-HR?

Yes. A204 Q&T has a typical yield strength of 405 MPa (58.7 ksi) against 315 MPa (45.7 ksi) for A204-HR — about 29% more. Tensile strength is 570 MPa (82.7 ksi) vs 520 MPa (75.4 ksi).

Which condition does FabDigit quote by default, HR or Q&T?

HR is the default A204 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, A204-HR or A204 Q&T?

A204-HR. Its machinability rates good (58/100) against fair (52/100) for A204 Q&T; for welding the order is A204-HR first (very good, 70/100) then A204 Q&T (good, 65/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A204-HR and A204 Q&T 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.