Chapter 1 - An introduction to welding of metallic materials

Abstract

In this chapter, a short history of the welding process is given, in addition to the stages that welding processes were developed in the last century until now. A brief introduction of the principles of different types of welding processes based on the used source of energy is shown. Different types of welding processes are explained briefly. More details about manual metal arc welding are given as an example of arc welding. The metallurgical aspects and weldability of the metals, steel-based alloys, in particular, are explained, especially in fusion welding processes, with or without using filler metals, considering the effect of the chemical composition and microstructures of the fusion zone and heat-affected zone on the whole behavior of the weldments. General welding defects in metallic alloys are shown either in the fusion or solid-state welding methods. Moreover, pre and/or postheat treatments, to minimize the defects and residual stresses are shown. Appropriate testing methods to evaluate the mechanical and corrosion behavior of the weldments are explained. At the end of the chapter, the general advantages and disadvantages of welding processes are listed.