309S is a free cutting stainless steel containing sulfur, which is mainly used for occasions requiring high degree of free cutting and surface smoothness.
309S Equivalent to GB 0Cr23Ni13, and American standard S30908 (AISI, ASTM).
309S is a variant of low carbon 309 stainless steel, used in welding applications. The lower carbon content minimizes the amount of carbide precipitated in the heat-affected zone near the weld seams, which may lead to intergranular corrosion (weld erosion) of stainless steel in some environments.
Chemical Composition
Element | Content (%) |
Iron, Fe | 60 |
Chromium, Cr | 23 |
Nickel, Ni | 14 |
Manganese, Mn | 2 |
Silicon, Si | 1 |
Carbon, C | 0.080 |
Phosphorous, P | 0.045 |
Sulfur, S | 0.030 |
Physical Properties
Density | 8 g/cm3 | 0.289 lb/in³ |
Melting point | 1454°C | 2650°F |
Mechanical Properties
Tensile strength, ultimate | 620 MPa | 89900 psi |
Tensile strength, yield (0.2%) | 310 MPa | 45000 psi |
Izod impact | 120 - 165 J | 88.5 - 122 ft-lb |
Modulus of elasticity | 200 GPa | 29000 ksi |
Shear modulus | 77 GPa | 11200 ksi |
Poissons ratio | 0.3 | 0.3 |
Elongation at break (in 50 mm) | 45% | 45% |
Hardness, Brinell (converted from Rockwell B hardness) | 147 | 147 |
Hardness, Knoop (converted from Rockwell B hardness) | 164 | 164 |
Hardness, Rockwell B | 85 | 85 |
Hardness, Vickers (converted from Rockwell B hardness) | 169 | 169 |
Thermal Properties
Thermal expansion co-efficient (@ 0-100°C/32-212°F) | 14.9 µm/m°C | 8.28 µin/in°F |
Thermal conductivity (@0-100°C/32-212°F) | 15.6 W/mK | 108 BTU in/hr.ft².°F |