Experimental Investigation and Weld Characterization Analysis on Carbon Steel by using Nd:Yag Laser Welding

Abstract

Laser welding is a compulsion in attaining certain structures and in situations demanding high-temperature resistance in one area and corrosion resistance in another. The objective of this study is to increase the efficiency of the weld joints and to study their properties. This study is aimed at optimizing the fastening method parameters to improve the life and efficiency of C45 carbon steel joint. Laser welding of C45 carbon steel plates is done without any prior heat treatment with a Nd:YAG laser pumped by a flash lamp that produces a pulsed output. Laser welding is carried out by varying parameters like Laser Power, Pulse Width, and Frequency thereby varying the laser penetration power and the bead formation that occurs in the weld area. Optimum laser welding parameters that yield maximum weld strength and minimum heat affect zone are found experimentally. The focal diameter was fixed at 1.8mm and the other three parameters: Power, Pulse Width, and Frequency were varied to evaluate the best combination. Experimental parameters were selected through Taguchi design using the L9 orthogonal array. The welded joints have also been subjected to microstructure test, tensile strength, and hardness to evaluate its metallurgical and mechanical properties.