PRODUCTION OF PURE TITANIUM OR LOW TITANIUM ALLOY ELONGATION MATERIAL

摘要

PURPOSE: To produce a titanium elongation material free from exposure of macrostructure after corrosion by subjecting a slab, composed of pure titanium or low titanium alloy, to plastic working in an α-region and then to reheating to β-region to perform inverse transformation from α-phase to β-phase. ;CONSTITUTION: A slab composed of pure titanium or low titanium alloy and composed essentially of α-phase in the α-region not higher than the β-transformation temp. is subjected to plastic working in the α-region and then to reheating to the β-region, by which inverse transformation from the α-phase to the β-phase is performed. Further, plastic working in the α-region is performed ordinarily in the temp. region (about 850°C) where hot working for titanium is made possible, at ≥ about 30% draft. Moreover, as heating conditions up to a temp. not lower than the β-transformation temp., a temp. of ≥ about 900°C suffices for the inverse transformation from the α-phase to the β-phase because β-transformation temp. is about 882°C. By this method, the titanium elongation material, free from exposure of macrostructure to the surface even if used under a sever corrosive environment, can be obtained.;COPYRIGHT: (C)1996,JPO