A method for the production of corrosion-resistant welded tubes made from titanium - alloy.

摘要

PURPOSE:To produce a welded Ti alloy tube excellent in crevice corrosion resistance by subjecting a slab of Ti alloy in which specific amounts of platinum group elements, Co, Ni, etc., are incorporated into Ti to heat treatment and to hot rolling under respectively specified conditions or further to cold rolling and then welding the resulting plate or sheet. CONSTITUTION:An ingot of a Ti alloy which has a composition consisting of, by weight, 0.01-0.14%, in total, of one or =2 kinds among platinum group elements, either or both of 0.1-2.0% each of Co and Ni, 0.35% O, 0.30% Fe, and the balance Ti or further containing one or more elements among 0.1-2.0% each of Mo, W, and V is heated at a temp. in the range between 750 deg.C and (beta-transformation point + 200 deg.C) and worked into slab state. This Ti alloy slab is heated up to a temp. between 550 deg.C and (beta-transformation point + 150 deg.C) and hot-rolled at =400 deg.C finishing temp. Subsequently, the resulting hot rolled plate is welded so as to be formed into a tube made of Ti alloy and this tube is subjected, if necessary, to annealing at a temp. between 400 deg.C and (beta-transformation point + 20 deg.C), or, the above hot rolled plate is cold-rolled and the resulting cold rolled sheet is annealed and welded into tubular shape.