S. Arungalai Vendan works as Associate Professor in Industrial Automation and Instrumentation Division, Dayananda Sagar University, India.

Physics of welding involves terminologies that are confluence of concepts from materials science, metallurgy, arc physics, electromagnetics, mechanical, power electronics and mathematics. Advent of sophisticated materials for versatile applications in industrial sectors demands them to demonstrate key features such as easy machinability and weld feasibility. Joining of materials is important in structures that are complex.

 

Further, the hybrid components in aero parts, defence arms and ammunitions, electric vehicles, flexible electronics etc necessitates the fabrication of structures with dissimilar material joints. Welding processes are chosen based on the material properties and behaviours such as differential thermal coefficients, metallurgical phenomenon, mechanical properties, molecular diffusion patterns and ionization potentials.

 

The identification of a specific joining process is based on the governing process parameters, economic viability and the joining mechanism adopted which may be either through heat/ pressure or with both heat and pressure. The physics of heat generation that may be due to arcs, plasmas, ultrasonic, electric resistance, explosion typically dictates the strength and quality of the weldment along with their metallurgical integrity. The methodology espoused for simplifying the herculean task of process identification for 21st century materials from the insights of physics and governing mathematical equations is discussed.