Stainless steel I-beams are made of 201(1Cr17Ni5Mn6N), 202(2 Cr13Mn9Ni4), 301(1 Cr17Ni7), 303(Y1Cr18Ni9), 304(OCr18Ni9), 304L (03 Cr19Ni10), 316(0 Cr17Ni12Mo2), 316L(00 Cr17Ni14Mo2), 321 (1 Cr18Ni9Ti), 420( 2cr13), 310S(0 Cr25Ni20), etc. The chemical composition of stainless steel I-beams belongs to general structural rolled steel series, the main test indexes were C, Mn, P and S. According to different grades, the content varies, the approximate range is C<0.08%, Mn: 2.0, P<0.035%, S<0.03%. Materials are widely used in hardware products, medical machinery, food machinery, ships, automobiles, doors and windows, furniture, large machinery, etc.