SX 309 Technical Data

Summary

SX 309 is a highly alloyed austenitic stainless steel used for its excellent oxidation resistance, high temperature strength and creep resistance. The lower nickel content of SX309 improves resistance to sulphur attack at high temperatures. It is tough and ductile, and can be readily fabricated and machined. SX 309S is the low-carbon version of SX 309, and is recommended for applications where sensitisation, and subsequent corrosion by high temperature gases or condensates during shutdown may pose a problem.

Typical Applications
SX 309 / 309S is used exclusively for its high temperature oxidation resistance. It is common for SX 309, 310 and 321 to be used in the same piece of equipment in the various temperature regions.

Typical Properties in the Annealed Condition
The properties quoted in this publication are typical of mill production and unless indicated should not be regarded as guaranteed minimum values for specification purposes.

Mechanical Properties at Room Temperature
Tensile Stength MPa min515

Proof Stress (0.2% Offset) MPa min205

Elongation (Percent in 50 mm) longitudinal 35% transverse 25%