ASTM 310S Stainless Steel: Ultra-High-Temperature Austenitic Grade for Severe Heat Environments

Properties of Grade 310/310S Stainless Steel

These grades contain 25% chromium and 20% nickel, making them highly resistant to oxidation and corrosion. Grade 310S is a lower carbon version, less prone to embrittlement and sensitisation in service. The high chromium and medium nickel content make these steels capable for applications in reducing sulphur atmospheres containing H2S. They are widely used in moderately carburising atmospheres, as encountered in petrochemical environments. For more severe carburising atmospheres other heat resisting alloys should be selected. Grade 310 is not recommended for frequent liquid quenching as it suffers from thermal shock. The grade is often used in cryogenic applications, due to its toughness and low magnetic permeability.

In common with other austenitic stainless steels, these grades cannot be hardened by heat treatment. They can be hardened by cold work, but this is rarely practiced.

Chemcial Composition of Grade 310/310S Stainless Steel

The chemical composition of grade 310 and grade 310S stainless steel are summarised in the following table.

Table 1. Chemical composition % of grade 310 and 310S stainless steel

Chemical Composition	310	310S
Carbon	0.25 max	0.08 max
Manganese	2.00 max	2.00 max
Silicon	1.50 max	1.50 max
Phosphorus	0.045 max	0.045 max
Sulphur	0.030 max	0.030 max
Chromium	24.00 - 26.00	24.00 - 26.00
Nickel	19.00 - 22.00	19.00 - 22.00