Grades of Stainless Steel for UHV

05/06/2015 - 04:42

The best grade of stainless steel is type 316LN (1.4429). It has  the lowest magnetic permeability, the best stability after machining and good TIG welding characteristics. It also has good corrosion resistance particularly against Chloride compounds. This material is expensive and tubes are generally not available.

The best compromise between price, performance and availability is grade 316L (1.4404). This material has very similar properties to 316LN. Good welding characteristics, corrosion resistance and mechanical hardness are very similar. The magnetic permeability can be as low as 1.005.

Summary of Composition and Vacuum Properties of Stainless Steels used for UHV.