Electron Beam Welding of Carbon Steel and Titanium Sheets Using Ag Insert Metal

概要

論文の詳細を見る
Electron-beam welding between low carbon steel and commercially pure titanium of 3mm thick sheets has been investigated using Ag insert metal. The effects of the thickness of Ag insert metal and the location of electron beam displaced onto either base metal on tensile strength of welded joint were investigated. Moreover, metallurgical investigations in weld metals such as distributions of Ti, Fe and Ag by means of EPMA and hardness distribution were discussed from the viewpoint of soundness in welded joint. As a result, there were cleared, in order to make the sound joint of steel-titanium using Ag insert metal, that little melting of titanium base metal was one of the most important factor during welding and less than 15wt.% of Ti concentration should be kept in Fe-Ti rich layer of boundary between Ag-and Fe-rich zones in weld metal, and that for practical purpose the location of electron beam impinged was displaced by about the radius of electron beam onto the steel side from the edge of titanium base metal. The strength of steel-titanium joint using Ag insert metal showed about 30kg/mm^2 in tensile test by an adoption of the optimum welding condition.