Effect of Welding Parameters on Structure- Property Correlation

In the course of manufacturing and fabrication, including processes like welding, metals and alloys are exposed to varying temperature-time thermal cycles, both during their production and for their service conditions (e.g., in vessels or pressure reactors). It is essential to carefully monitor these fabrication processes because they can lead to changes in the material’s microstructure, potentially resulting in loss of mechanical and corrosion characteristics. Various ferrous and non-ferrous materials are employed in joining processes for various applications, with stainless steels being the most common materials used across different sectors. The microstructural, mechanical, and susceptibility to corrosion of welded materials are significantly impacted by heat input (HI), which is regulated by welding processes and parameters like, voltage, welding speed and current. For instance, in stainless steels, HI significantly influences the solidification mode of the weld zone, which can vary between fully austenitic to austenitic-ferritic, ferritic-austenitic, or fully ferritic, and the eventual microstructure defines the mechanical and corrosion characteristics of weldments. Therefore, the present chapter delves into how HI impacts the welding characteristics of stainless steels.