Stainless Steel 303
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Material Data Sheet
The machineable nature of Grade 303 stainless steel is due to the presence of Sulphur in the steels composition. Whilst the Sulphur improves machining, it also causes a decrease in the corrosion resistance and a slight lowering of the toughness. The corrosion resistance of grade 303 stainless steel is lower than that for 304. The toughness is still excellent as with other austenitic grades.
Element | Content(%) |
---|---|
Iron, Fe | 69.00 |
Chromium, Cr | 18.00 |
Nickel, Ni | 9.00 |
Manganese, Mn | ≤2.00 |
Silicon, Si | ≤1.00 |
Carbon, C | ≤0.15 |
Phosphorus, P | ≤0.20 |
Sulfur, S | ≤0.35 |
Properties | Metric | Imperial |
---|---|---|
Density | 7.89 g/cc | 0.290 lb/in3 |
Melting Point | 1400 – 1420 °C | 2550 – 2590 °F |
Properties | Metric | Imperial |
---|---|---|
Hardness, Brinell | 228 | 228 |
Hardness, Knoop | 251 | 251 |
Hardness, Rockwell B | 96 | 96 |
Hardness, Rockwell C | 19 | 19 |
Hardness, Vickers | 240 | 240 |
Tensile Strength, Ultimate | 690 MPa | 100000 psi |
Tensile Strength, Yield | 415 MPa | 60200 psi |
Elongation at Break | 40% | 40% |
Modulus of Elasticity | 193 GPa | 28000 ksi |
Poisson’s Ratio | 0.25 | 0.25 |
Fatigue Strength | 240 MPa | 34800 psi |
Shear Modulus | 77.2 GPa | 11200 ksi |
Properties | Metric | Imperial |
---|---|---|
CTE, linear 20°C | 17.2 µm/m-°C | 9.56 µin/in-°F |
Specific Heat Capacity | 0.5 J/g-°C | 0.12 BTU/lb-°F |
Thermal Conductivity | 16.2 W/m-K | 112 BTU-in/hr-ft²-°F |
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Stainless Steel 303 is used in the following application areas:
- Aircraft applications including fittings, shafts and spindles
- Automatic screw machine applications
- Medical devices with screw threads, drilled or tapped holes
- Pump and valve parts
- Architectural applications
- Nuts and bolts
Key Words: T303, T 303, 303SS, 303 SS, AFNOR Z 10 CNF 18.09 (Fr), UNI X 10 CrNiS 18 09, SUS 303, SS14 2346 (Sweden), B.S. 303 S 21, UNS S30300, AMS 5640 (1), ASME SA194, ASME SA320, ASTM A194, ASTM A314, ASTM A320, ASTM A320, ASTM A473, ASTM A581, ASTM A582, MIL SPEC MIL-S-862, SAE J405 (30303), DIN 1.4305, X12CrNiS188, EN 58M, austenitic, ISO 683/13 17, 18-8