Alloy 310 (UNS S31000) is an austenitic stainless steel for use in high temperature corrosion resistant applications. This alloy resists oxidation up to 2010 oF (1100 oC) under mildly cyclic conditions.
As a result of its high chromium and moderate nickel content, Alloy 310 is resistant to sulfidation and can also be utilized in moderate carburized atmospheres. The more severe carburizing atmospheres of thermal process equipment usually require nickel alloys such as 330 (UNS N08330). Alloy 310 can be used in slightly oxidizing, nitriding, cementing and thermal cycling applications, although the maximum service temperature must be lowered. Alloy 310 also finds usage in cryogenic applications with low magnetic permeability and toughness down to -450 oF. When heated between 1202 oF – 1742 oF, the alloy is subject to sigma phase precipitation. A solution annealing treatment at 2012 oF – 2102 oF (1100 oC – 1150 oC) will restore a degree of toughness.
Like most of the austenitic stainless steels, this alloy can be readily welded using fusion or resistance methods. Oxyacetylene welding should not be used. Filler metal should be AWS E/ER 310.
310S (UNS S31008) is the low carbon version of the alloy. It is utilized for ease of fabrication. 310H (UNS S31009) is a high carbon modification developed for enhanced creep resistance. In most instances the grain size and carbon content of the plate can meet both the 310S and 310H requirements. Alloy 310 can be easily welded and processed by standard shop fabrication practices. This alloy does not respond to heat treatment. Cold work will effect an increase in both hardness and strength.