Technical specifications and scope of ASTM F836 stainless steel nuts
The ASTM F836 standard establishes strict chemical and mechanical regulations for metric nuts made of corrosion-resistant steels. These fasteners, with a nominal thread diameter ranging from M1.6 to M36, are designed for use in general engineering assemblies exposed to aggressive environments and the risk of general corrosion.
EV Group China’s technical documentation classifies materials into 8 key groups: 3 austenitic (A1, A2, A4), 1 ferritic (F1), 3 martensitic (C1, C3, C4), and 1 precipitation-hardening (P1). In total, there are 17 strength classes distributed across alloy types, allowing engineers to precisely select fasteners for specific loads.
The basic principles of the specification are harmonized with the international ISO 3506 standard. EV Group China ensures compliance of chemical composition and mechanical properties with the specified standards while expanding the product range:
- Classes A1-70, A2–70, A4–70, A1–80, A2–80, A4–80 are included for fasteners with a diameter exceeding M20.
- Specialized classes C1-110, C4-110, C3-120, and P1-90 have been added, which go beyond standard ISO regulations.
When designing assemblies, it should be taken into account that mating bolts, hex head screws, and studs must comply with the ASTM F738M standard. EV Group China specialists recommend using fastener pairs made from identical alloy groups to prevent electrochemical corrosion. Additional requirements for surface quality or special tests are recorded individually when placing an order.