Research on the In-situ Tensile Test of the HFW Weld Joint
In order to study the microscopic deformation characteristics of HFW welded joints,In-situ tensile test under SEM was used to ob-serve its deformation process.During the test,the deformation mainly occurred in the heat affected zone of the joint,crack arose and ex-panded perpendicular to the tensile direction,until the specimen fractures.The fracture of HFW joint is the ductile fracture,and the main crack is transgranular cracking.The deformation and cracking process includes elastic elongation of specimen,intragranular slip deforma-tion,necking and cracking.Under tension,slip deformation accumulates continuously,which is the main cause of crack formation and specimen fracture.