Research on Parameters of Wire-Filling Laser Welding and Quenching Process for Joints Microstructure and Mechanical Property of BR1500HS Steel

With the aim to investigate effect of parameters and quenching process on joint microstructure mechanical properties hot stamping steel by laser welding, BR1500HS boron was welded wire-filling welding with ER70-G wire under different parameters. The specimens were heated 900 °C held for 5 min before water quenching. A universal material test machine, optical microscope, Vickers hardness tester, scanning electron backscatter diffraction (EBSD) used characterize. results show that heat input should be greater than 1040 J/cm optimal wire-feeding speed is between 160 cm/min 180 cm/min. tensile strength quenched can reach 1601.9 MPa at compatible More retained austenite distributes in fusion zone (FZ) fine grain (FGZ) coarse (CGZ) However, FZ heat-affected (HAZ) decreases clearly uniformly after diameter not uniform there are some grains 40 μm. After quenching, refined more joint. increase input, microhardness HAZ from 500 HV 450 HV. if increases, increases all samples 550 fracture morphology consists a large number dimples little river patterns. amount patterns cleavage facets due generation martensite.