Temperature and displacement fields measurements to assist the numerical simulation of the welding-brazing process of thin automotive parts

摘要

This study is dedicated to a laser welding-brazing process used to assemble thin automotive thin sheets. ABAQUS general-purpose finite element code is used to simulate this assembly process. The welding-brazing heat source is modelled as the combination of a 3D volumetric source corresponding to the welding-brazing joint, and a 2D surface source corresponding to the heat flux emitted by the laser beam onto the sheets in the vicinity of the joint. The thermal contact between the assembled sheets is modelled as a thermal resistance that depends on the pressure between the sheets when they are in contact, or the distance between them when they are apart. Identification of heat source and contact models is derived from the results of welding-brazing tests instrumented with thermocouples and InfraRed (IR) cameras. Micrographic observations in the vicinity of the welding-brazing joint are used to (partially) validate the numerical predictions of the Heat Affected Zone (HAZ).