METHOD FOR PRODUCING AN ARTICLE BY SUPERPLASTIC SHAPING AND DIFFUSION WELDING

摘要

The invention relates to plastic metal forming, particularly to methods of manufacturing articles of titanium alloys by superplastic forming and diffusion welding. The method is particularly applicable to aircraft engine building for manufacturing articles, e.g. fan blades, A method of manufacturing an article by superplastic forming and diffusion welding from at least two workpieces of a titanium alloy, including: marking areas to be and not to be bonded on a surface of at least one of the workpieces; assembling the workpieces into a stack; heating the stack to a predetermined temperature T and applying a pressure of a predetermined value p from a press for diffusion welding of the workpieces together to produce a semifinished article; heating and supplying a pressurized working fluid into the interior of the semifinished article to superplastically form at least one of the workpieces to produce an article of a predetermined shape, characterized in that the diffusion welding is carried out through pads of a titanium alloy having a smaller flow stress than that in the workpieces, wherein mainly in the case when the article is made from three or more workpieces a bond preventing material is applied to at least a part of a surface of at least one of the workpieces at the areas not to be bonded.