A Critical Study of Input Process Parameter on Weld Geometry and Characterizations of Cobalt-Based Super Alloy L605 Sheets

The Cobalt-based L605 super alloy have been considered for the laser welding purpose due its wide application in defence technology, aerospace, gas turbine and industrial furnace and liners in high-temperature kilns. So, this chapter focus on the similar laser welding of L605—Co-based super alloy sheets. The process parameter like laser power and scanning speed on weld top and bottom width, micro hardness, HAZ and welding strength of the weld joints were investigated. As the scanning speed increases, the top and bottom width reduces to minimum and power of 1600 W and 400 mm/min are the near optimum process parameter for the fabrication of sound quality of weld. The hard phase like CrCo are observed at the weld zone which enhance the micro hardness, which is found to be maximum of ~ 320 HV0.1. The ductile failure of the welded specimen are confirmed from the FESEM analysis, which indicate the presence of dimples, inter-granular cleavage, and micro voids in the fracture zone. The average grain size of the phase formed at the HAZ are 21.52 (µm), it has been observed. The maximum tensile strength (~ 1000 MPa) are found.