Production manner null of the cold-rolled board of the titanium or titanium alloy where the surface

摘要

PURPOSE: To obtain a Ti (alloy) cold-rolled sheet small in surface flaws by subjecting the hot rolled sheet of Ti (alloy) to shot blasting treatment, thereafter executing pickling and annealing and dispering oxygen in an oxygen-enriched layer therein. ;CONSTITUTION: The hot-rolled sheet of Ti (alloy) is subjected to shot blasting treatment to destroy an oxidized scale film on the surface, then is pickled by nitric-hydrofluoric acid to remove the film by 5 to 30μm total sheet thickness in both faces. The Ti (alloy) sheet after being subjected to the pickling is annealed at 600 to 850°C for 2hr or a longer time in a nonoxidizing atmosphere to diffuse oxygen in the oxygen-enriched layer into the inside of the Ti sheet. Then, it is subjected to cold rolling to obtain the Ti (alloy) cold-rolled sheet small in surface flaws.;COPYRIGHT: (C)1994,JPO&Japio