The stainless steel fastener materials are
identified as the B8 class of alloys and are identified in the ASTM Specification A193/193M (Standard Specification for Alloy Steel and Stainless Steel Bolting Materials for High Temperature Service). The corresponding nut specification is ASTM Specification A194/194M.
ASTM Specification F593 (Standard Specification for Stainless Steel Bolts, Hex Cap Screws and Studs) covers the
broad range of commercial ferritic, martensitic and precipitation hardened grades of stainless steel, 0.25 to 1.5 inch nominal diameter.
These specifications cover the 300 series stainless steels and high man- ganese and high silicon austenitic grades, all of which are essentially 18-8 (18% chromium and 8% nickel) materials, with compositions very close to the nomi- nal composition for Type 304. Because they have similar corrosion resistance properties, these 18-8 materials are often interchanged in fastener applications. If an application calls for Type 304, the designer can generally specify an 18-8 (Grade 8) fastener material. Find out more at fasteners oklahoma city.
Most AISI stainless steels are identified by a system of numbers in either 200, 300, or 400 Series. In addition, all are identified by the Unified Numbering System (UNS). For example, Type 304 is Type S30400 in UNS. Special analysis and proprietary stainless steels are identified by trade names, some of which may resemble AISI numbers.
There are five primary classifications of stainless steel:
Austenitic Martensitic Ferritic
Precipitation hardening Duplex