Stainless Steel Grade 309S - High Temp Alloy Steel Grade

309/309S Stainless Steel Chemical Composition

The only significant difference between 309 and 309S is the carbon content. Alloy 309S has a much less carbon composition (0.08% max) which minimizes carbide precipitation and improves weldability 309H has carbon content range from 0.04 to 0.10%. 309/309S Stainless Steel is a chromium-nickel stainless grade, 22-24% chromium, with Min. 12% Nickel content, this gives Alloy 309/309S good corrosion resistance at elevated temperatures.

	C	Mn	Si	P	S	Cr	Ni	Fe
309	0.20 Max	2.0 Max	0.75 Max	0.045 Max	0.03 Max	Min: 22.0 Max: 24.0	Min: 12.0 Max: 15.0	Balance
309S	0.08 Max	2.0 Max	0.75 Max	0.045 Max	0.03 Max	Min: 22.0 Max: 24.0	Min: 12.0 Max: 15.0	Balance
309H	Min: 0.04 Max: 0.10	2.0 Max	0.75 Max	0.045 Max	0.03 Max	Min: 22.0 Max: 24.0	Min: 12.0 Max: 15.0	Balance

* Maximum, unless range is indicated

309/309S Stainless Steel Mechanical Properties

Grade	Tensile Strength Mpa(Min)	Yield Strength 0.2% Mpa (Min)	Elongation %	Hardness (Brinell) MAX
309/H	515	205	40	217

309/309S Stainless Steel Physical Properties

Density Lbm/In^3	Thermal Conductivity (BTU/H Ft. °F)	Electrical Resistivity (In X 10^-6)	Modulus Of Elasticity (Psi X 10^6)	Coefficient Of Thermal Expansion (In/In)/ °F X 10^-6	Specific Heat (BTU/Lb/ °F)	Melting Range (°F)
At 68°F: 0.285	9.0 At 32- 212°F	30.7 At 68°F	28.5	8.28 At 32 – 212°F	0.1200 At 68°F To 212°F	2500-2590