Study on Tensile Mechanical Properties of TC4 Titanium Alloy Fiber Laser Welding Joint Based on Infrared Thermal Imaging
PENG Huan1,2, DUAN Aiqin2, DU Xueming1
(1. School of Material Science and Engineering, Wuhan University of Technology, Wuhan 430070, China;
2. AVIC Manufacturing Technology Institute, Beijing 100024, China)
Abstract：Studying on the tensile mechanical properties of butt joint of 2.5mm thick TC4 welded by fiber laser, of
which research method is applying synchronous infrared thermal imaging in conventional tensile experiment, real-time according
the change of temperature field of specimen in tensile experiment. Conventional tensile experiment results show
that the welded joint has similar strength but of which the elongation rate just reached 59.53% of base material. The specimen
temperature field test results show that: when the axial loads is below the load corresponds to the yield strength, larger
yield strength area appears in the heat affected zone of welded joint, but significant plastic strain did not appear. When the
load is equal to the load corresponding to yield strength, the micro plastic deformation appears before macroscopic yield
point. When the load is equal to the load corresponding to tensile strength, the length of severe plastic deformation zone
of joint reaches only 35% of the base metal, and the length of severe plastic deformation zone gradually increases with the
stretching process.
2017, 
