The general term for metal and non-metal products and accessories installed in buildings or structures. Generally, the utility model has double effects of utility and decoration. Door hardware refers to all kinds of metal and non-metal accessories installed on the building door. There are building lock, handle, support, hinge, door closer, handle, bolt, anti-theft chain, door closing device, etc.

IntroductionAustenitic stainless steels are generally non-magnetic with magnetic permeabilities of around 1.0. Permeabilities above 1.0 are associated with the amount of either ferrite or martensite phases present in the 'austenitic' steel and so depend on:chemical composition cold work and heat tr