US 309/309S (UNS S30900/S30908) steel

TYPES 309 AND 309S are austenitic chromium-nickel stainless steels that provide excellent corrosion resistance and heat resistance plus good strength at room and elevated temperatures. Type 309S is identical to Type 309 except for a lower carbon content that minimizes carbide precipitation and improves weldability.

Alloy 309 and 309S is best known for high temperature service. This alloy works well up to 2000 °F, especially if oxidation resistance is required. 309 and 310 stainless steel are premier high temperature performers among the common stainless grades available from our stock. High nickel and chromium content and a coarse grain structure result in:

• Improved resistance to cyclic oxidation
• Increased resistance to sulfidation
• Better high temperature strength
• Improved resistance to intergranular corrosion

309S (UNS S30908) stainless steel is the low carbon version of the alloy. It is utilized for ease of fabrication.

309H (UNS S30909) is a high carbon modification developed for enhanced creep resistance. It most instances the grain size and carbon content of the plate can meet both the 309S and 309H requirements. When heated between 1202 – 1742°F (650 – 950°C) the alloy is subject to sigma phase precipitation. A solution annealing treatment at 2012 – 2102°F (1100 – 1150°C) will restore a degree of toughness. Alloy 309 can be easily welded and processed by standard shop fabrication practices.

Chemical Composition

Grade	C	Si	P	S	Cr	Mn	Ni	Fe
309	0.20 max	1.0 max	0.045 max	0.030 max	22.0 - 24.0	2.0 max	12.0 - 15.0	Remainder
309S	0.08 max	1.0 max	0.045 max	0.030 max	22.0 - 24.0	2.0 max	12.0 - 15.0	Remainder

Mechanical Properties

Grade	Tensile Strength (ksi)	0.2% Yield Strength (ksi)	Elongation% in 2 inches
309	75	30	40
309S	70	25	40

Physical Properties

	309	309S	Temperature in °C
Density	7.9 g/cm³	8.03 g/cm³	Room
Specific Heat	0.12 Kcal/kg.C	0.12 Kcal/kg.C	22°
Melting Range	1399 - 1454 °C	1399 - 1454 °C	-
Modulus of Elasticity	200 KN/mm²	200 KN/mm²	22°
Electrical Resistivity	78 µΩ.cm	78 µΩ.cm	Room
Coefficient of Expansion	14.9 µm/m °C	14.9 µm/m °C	20 - 100°
Thermal Conductivity	15.6 W/m -°K	15.6 W/m -°K	20°

FAQ
Q. Can I have a sample order for stainless steel sheet plate products?
A: Yes, we welcome sample order to test and check quality. Mixed samples are acceptable.

Q. What about the lead time?
A:Sample needs 3-5 days;

Q. Do you have any MOQ limit for stainless steel sheet plate products order?
A: Low MOQ, 1pcs for sample checking is available

Q. How do you ship the goods and how long does it take to arrive?
A: We usually ship by DHL, UPS, FedEx or TNT. It usually takes 3-5 days to arrive. Airline and sea shipping also optional. For mass products, ship freight is prefered.

Q. Is it OK to print my logo on products?
A: Yes. OEM and ODM are available for us.

Q: How to ensure the quality?
A:Mill Test Certificate is supplied with shipment. If needed, a Third Party Inspection is acceptable