This specification covers the chemical and mechanical requirements for style 1 stainless steel metric nuts. Groups and property classes of austenitic, ferritic, martensitic, and precipitation hardening stainless steel alloys are covered. Materials shall be cold-formed, hot-formed, or machined form, and shall conform to chemical, mechanical, dimensional and surface finish properties. Stainless steel shall also conform to heat treatment requirements depending on material grade. The material shall be capable of passing chemical, mechanical, and corrosion resistance tests in accordance to the specification. Product marking and packaging shall conform to the requirements of the specification.

1.1 This specification covers the chemical and mechanical requirements for stainless steel metric nuts with nominal thread diameters M1.6 through M36 and intended for use in engineering applications requiring general corrosion resistance.

1.2 Eight groups of stainless steel alloys are covered, including three austenitic (Grades A1, A2, and A4), one ferritic (Grade F1), three martensitic (Grades C1, C3, and C4), and one precipitation hardening (Grade P1).