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Steel 3J53-ST vs 3J53 ST+A

Steel · 3J53 temper comparison

3J53-ST and 3J53 ST+A are two conditions of the same steel grade, 3J53: ST (solution annealed) versus ST+A (solution treated and precipitation aged). The chemistry is identical, so every difference below comes from the condition. 3J53 ST+A is the stronger of the two: yield strength 830 MPa (120 ksi) against 330 MPa (47.9 ksi) for 3J53-ST, about 152% more; tensile strength follows at 1,180 MPa (171 ksi) vs 760 MPa (110 ksi). In exchange, 3J53-ST is the more ductile: elongation 35% versus 15% for 3J53 ST+A, and 3J53 ST+A is harder (355 HV vs 180 HV). 3J53 ST+A is stiffer (170 GPa vs 155 GPa) and 3J53 ST+A runs hotter in service (200°C vs 150°C continuous). On the shop floor, 3J53-ST machines more easily (fair vs poor).

3J53-STChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

3J53 ST+AChoose it when strength drives the design, or when the part sees heat.

3J53-ST vs 3J53 ST+A: properties

3J53-ST3J53 ST+A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

155 GPa22.5 Msi
170 GPa24.7 Msi

Tensile Strength (Ultimate)

760 MPa110 ksi
1,180 MPa171 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
830 MPa120 ksi

Elongation at Break

35%
15%

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
450 MPa65.3 ksi

Hardness, Vickers

180 HV
355 HV

Same in both: Shear Modulus 63 GPa9.1 Msi · Bulk Modulus 145 GPa21 Msi · Poisson's Ratio 0.31 · Reduction in Area 55% · Compressive Strength 340 MPa49.3 ksi · Shear Strength 480 MPa69.6 ksi · Charpy V-Notch Impact (RT) 90 J66.4 ft·lbf · Hardness, Brinell 172 HB · Hardness, Rockwell B 88 HRB

Physical

Density and transition temperatures.

Same in both: Density 8.14 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Max Service Temperature (continuous)

150°C302 °F
200°C392 °F

Same in both: Thermal Conductivity 12.6 W/m·K7.3 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 7.9 µm/m·K4.4 µin/in·°F · Min Service Temperature -50°C-58 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.2 % IACS · Electrical Resistivity 8×10⁻⁷ Ω·m31.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.35 V · Corrosion Resistance 40 / 100

Manufacturability

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

Machinability

35 / 100
22 / 100

Formability (cold)

75 / 100
25 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 30% · Weldability 50 / 100 · Brazeability / Solderability 55 / 100 · Polishability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 130 MJ/kg55,890 BTU/lb · Embodied Carbon (primary production) 9 kg CO₂/kg · Embodied Water 220 L/kg26.4 gal/lb · Typical Recycled Content 20%

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 scale3J53

3J53-ST vs 3J53 ST+A — frequently asked

Is 3J53 ST+A stronger than 3J53-ST?

Yes. 3J53 ST+A has a typical yield strength of 830 MPa (120 ksi) against 330 MPa (47.9 ksi) for 3J53-ST — about 152% more. Tensile strength is 1,180 MPa (171 ksi) vs 760 MPa (110 ksi).

Which condition does FabDigit quote by default, ST or ST+A?

ST is the default 3J53 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, 3J53-ST or 3J53 ST+A?

3J53-ST. Its machinability rates fair (35/100) against poor (22/100) for 3J53 ST+A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 3J53-ST and 3J53 ST+A 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.