Mechanical properties and fracture behaviors in remote laser spot welding of quenching and partitioning 980 steel

Abstract Quenching and partitioning (QP (II) crack propagation along the thickness and circumference of the joint; (III) crack propagation along the circumference of the joint; and (IV) instantaneous fracture. Furthermore, it was found that the coarse grain heat affected zone (CG-HAZ) has a lowest fraction of high-angle grain boundaries (HAGBs), resulting in the crack propagated along the CG-HAZ during stage II. During crack propagation, the fracture took place as a ductile fracture, but the instantaneous fracture occurred in quasi-cleavage characteristic.