Study on the Microstructures and Properties of TC4 Alloy Joints Welded bythe Electron Beam

摘要

Study on the microstructures and properties of TC4 alloy joints welded by the electron beam arerninvestigated by room-temperature tensile test, room-temperature notch tension test, microhardnessrntest and metallographic analyse. The results show that the joints with good performance of TC4 alloyrnmay be obtained by means of electron beam welding (EBW in short). The tensile strength of weldedrnseam is not less than the base, and the notch sensitive coefficient of the welded seam is less than 1.rnThe hardness of the welded seam and the HAZ are also higher than that of the base metal. Thernmicrostructure of the welded seam is α'phase (needle martensite) which is transformed from thernprimary coarse β matrix, and that of the HAZ is the mixture of fine needle martensite and the primary αrnphase.