The keyhole welds are produced by the use of highconstrictedarcof plasma arc joining operation. Although, keyhole stability is one the major issue which will determine overall stability of the joining process and weld integrity. In the current article, a 3D model is developed to examine the effect of process parameters and investigate the flow behavior in the melt pool during joining operation. In the present analysis, ANSYS-WORKBENCH environment is utilized to develop a 3D physical model of the specimen.