Low nickel@ content steel alloy for jewellery, etc - comprises silicon@, manganese@, nitrogen@, chromium@, phosphorus@, sulphur@, copper@ and molybdenum@

摘要

Iron-based alloy is used to make objects in constant contact with human skin and contains in wt.%: less than 0.015 C; less than 0.5 Si; 21-35 Mn, 0.3-0.7 N; 9-20 Cr; less than 0.02 P; less than 0.02 S; 0-4 Cu; 0-7 Mu; balance Fe plus usual impurities. The alloy is used in wire form which is soft annealed before being cold drawn by 10-20%. This provides it with the elasticity required during its working life. USE/ADVANTAGE - The alloy is used for making glasses' frames (claimed), earrings, jewellery (e.g. chains, rings) watch casings and studs for jeans. Does not give off unacceptable amounts of Ni to the human skin. Is workable and has good corrosion resistance. In an example, an alloy has the following compsn. (wt.%): 0.007 C, 0.18 Si, 24.8 Mn, 0.42 N, 14.7 Cr, 0.01 Ni, 0.005 P, 0.007 S, 0.02 Cu and balance Fe.