Estudo da viabilidade técnica da soldagem por fricção de barras cilíndricas de titânio em um torno convencional

Abstract

Conventional friction welding, invented in 1939 by the Soviet Union, has been applied in various scopes and is an important tool when it is desired to weld bodies at temperatures below melting. The work in question was based on applying this technique in a conventional adapted lathe, using Ti-Al-4V titanium alloy as raw material. The imported raw material was supplied by a medical equipment partner company that is looking for a way to establish a permanent joint of this biocompatible material. Based on technical literature, the study addresses the welding application methodology, covering from applied forces, lathe rotation, set up used and process particularities. To define the rotation of 2500 rpm used in the final tests, preliminary welds performed at different rotations were submitted to tensile tests and their results were compared. With the process and parameters defined, seven welded specimens were analyzed for tensile strength, metallography and microhardness. Despite some disagreement as to the coaxiality of the parts, in general, the welds presented satisfactory results, supporting on average a traction of 908 Mpa and presenting a 100 HVN increase in the central region of the weld, according to foreign studies with specific equipment application of titanium friction welding. As the main objective was to join cylindrical parts through grade 5 titanium friction welding, increasing their mechanical strength, we consider that the work was successful in its purpose.