Electron beam welding of SiCp/Al composite to Ti-6Al-4V

Abstract

In this paper, the weld appearance, microstructures and mechanical properties of electron beam welding-welded joints of SiCp/Al composite and Ti-6Al-4V were studied. The results showed that the weld appearance and mechanical properties were poor when the heat source was located at the middle of the butt joint. The weld was mainly composed of Ti₃Al intermetallic compounds, but large amounts of Al₄C₃ brittle phase appeared at the fusion line close to the SiCp/Al composite. The weld appearance was improved by deviating the heat source towards the Ti-6Al-4V side. The microstructures of the weld changed into an α(α')+β dual-phase structures and the amounts of Al₄C₃ brittle phase decreased. A well-formed joint with a tensile strength of 108·9 MPa, 60% that of the base metal, was obtained when the heat source was deviated by 0·3 mm towards the Ti-6Al-4V side.

Keywords:

• SiCp/Al composite
• Ti-6Al-4V
• Electron beam welding
• Deflection electron beam welding
• Brittle phase