Do stainless steel fasteners need heat treatment

Whether stainless steel fasteners need heat treatment depends on their type and specific application scenarios

Classification of stainless steel fasteners and their heat treatment needs
Stainless steel fasteners are mainly divided into the following categories:

Austenitic stainless steels: such as 304 and 316, etc., these stainless steels cannot be hardened by heat treatment, and are mainly hardened by cold work forming. Heat treatment is mainly used to restore corrosion resistance and stress removal, such as solution treatment and stress relief treatment after welding

Ferritic stainless steels: such as 430, this type of stainless steel cannot be increased by heat treatment, but it can be annealed to restore ductility

Martensitic stainless steels, such as 410 and 431, are heat-treated in a manner similar to carbon and alloy steels, including austenitization and tempering

Effect of heat treatment on stainless steel fasteners
The influence of heat treatment on stainless steel fasteners is mainly reflected in the following aspects:

Solution treatment: improve corrosion resistance and eliminate cold work hardening, suitable for all components and grades of austenitic stainless steel, the heating temperature is generally 950 °C ~ 1050 °C, rapid cooling

Stabilization treatment: used for stainless steel containing titanium or niobium to obtain stable corrosion resistance, the heating temperature is generally between 750~860 °C

Sensitization treatment: used for specific occasions, heated to 650 °C, kept warm for 5~6 hours, and air-cooled, in order to assess the anti-intergranular corrosion ability of the material

Stress relief treatment: eliminate the stress generated during machining, heat to 1010~1120 °C, and cool slowly after heat preservation

Differences in heat treatment processes for different types of stainless steel fasteners
Austenitic stainless steels: Mainly hardened by cold work forming, heat treatment is mainly used to restore corrosion resistance and stress removal. Solution treatment and stress relief treatment are commonly used methods

Ferritic stainless steel: mainly hardened by cold work forming, heat treatment is mainly used to restore ductility, usually annealed

Martensitic stainless steels: Similar to carbon and alloy steels, including austenitization and tempering treatments for strength and ductility