Microstructures and Mechanical Properties of Electron Beam Welds in Thick-Section Titanium Alloy Plates
The application of thick-section titanium alloy plates in aerospace industries usually requires electron beam welding. Welding parameters can be adjusted to acquire welds with different geometric and microstructural features, which may yield welds of different mechanical properties. Due to the large thickness the properties of different location in the same weld may manifest some differences. So it is of great importance to investigate the microstructures and mechanical properties of thick-section welds. TA15 alloy plates of 45mm and 78mm in thickness are welded with several welding velocities respectively. The macro and microstructures, hardness distributions and mechanical properties of these welds are evaluated. The tensile strength and ductility of 45-mm thick plate welds are slightly higher than those of 78-mm thick plates. Increasing welding velocity can improve the weld strength. The impact toughness and fracture toughness of the lower part is less than that of the upper part for the same weld and reducing welding velocity can improve weld toughness obviously. It is found that the weld toughness is in good correlation with the weld width. With the increase of weld width the weld impact toughness increase slightly, while the fracture toughness increases more significantly. Finally these phenomena are explained with the microstructural investigations. The welds are predominantly made up of parallel plates and small amount of martensite or. The morphology of plates and the nature of supersaturation determine the weld properties. The reduction of toughness is aggravated by the increase of the weld supersaturation extent.
laser lap welding sus301l austenitic stainless steel welding deformation orthogonal experiments
S.Q.Guo B.Zhou W.H.Liu W.Y.Zhang X.J.Zhang N.Li
Beijing Institute of Aeronautical Materials, Beijing, China, 100095
国际会议
北京
英文
90-97
2010-10-25（万方平台首次上网日期，不代表论文的发表时间）