scope:

This specification covers iron-chromium-nickel alloy, stainless steel castings intended for particularly severe corrosive applications.

This specification requires postweld heat-treatment of all weld repairs affecting surfaces intended to be wetted by the corrosive medium. For applications for which postweld heat-treatment is not considered mandatory for retention of acceptable corrosion resistance, refer to M 163M/M 163.

Note 1-For general corrosion-resistant alloy castings, reference should be made to M 163M/M 163. For general heat-resistant alloy castings, reference should be made to ASTM A 297/A 297M. For nickel-base alloy castings, refer to ASTM A 494/A 494M.

The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the inch-pound units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. SI units are applicable for material ordered to M 285M and inch-pound units for material ordered to M 285.