To conduct a successful weld through MPW a threshold value of pressure must be exceeded. This pressure (-)-JQ1 given by the relation (Kore et al., 2010):equation(4)P=5×Hugoniot elastic limit(HEL)where HEL is given by the relation:equation(5)HEL=12(KG+43)Y0where K is the bulk modulus, G is the shear modulus and Y0 is the tensile yield stress.
Since the inception of the EXW process, an extensive study has been done in order to understand the process and its underlying principles and has led to the development of a number of weldability windows. Available information in the literature and experimental data on EXW has helped and guided researchers to work upon MPW. In both EXW and MPW processes, the same process parameters have influenced the resultant bond irrespective of whether a good weld is produced or otherwise. Researchers have thus relied upon the weldability windows developed for EXW to develop weldability windows specific to MPW. However, these weldability windows are specific to a general set of materials and geometries and can only be used to make a rough approximation of the parameter settings for MPW. Thus, development of a practical weldability window specific to MPW node of Ranvier can define accurate process parameters for producing a successful weld is the need of the hour.