Mechanical and metallurgical properties of pulsed neodymium-doped yttriurr aluminum garnet laser welding of dual phase steels

摘要

In this paper, the effect of energy input pattern in pulsed neodymium-doped yttrium aluminum garnet laser welding on mechanical and metallurgical characteristics of a 0.19% carbon dual phase steel is stud ied. The experimental results showed that the energy input pattern to the fusion zone had a significant effect on the ultimate tensile strength of the welded samples. The longitudinally and transversely tested weld specimens showed higher and lower strength than the base metal respectively. Increase in effective peak power density increased the volume of fusion zone which in turn caused an increase in the strength of the welded specimens. Microstructural studies showed coarse grains in the heat affected zone of welded samples especially at higher levels of pulse duration. Fracture studies showed presence of dim nles nn the frartnrpri surfaces nf the heat affected zone indicating that a ductile fracture had occurred.