Studies on phase transformation and mechanical properties in heat affected zone of quenched and tempered steel weldments

This study examines the mechanical characteristics and microstructural alterations in the Heat Affected Zone (HAZ) of quenched and tempered steel, a high-strength low alloy that is well-known for its remarkable toughness and yield strength. Elements like Cr and V are added to the alloy to improve hardenability and provide resistance to oxidation, corrosion, and wear. With applications in vital domains such as aerospace, motorsports, and rocket motor casings, comprehension of the weldment behavior is essential to guaranteeing structural integrity. A thorough analysis of the mechanical characteristics and microstructure of the quenched and tempered steel weldments is part of the methodology. While Cr and C help to improve elasticity, the presence of Cr and V affects the steel’s ability to harden. The study emphasizes the value of weld quality in high-stakes situations while concentrating on possible defense uses. The microstructure and hardness of the quenched and tempered steel weld are demonstrated by the study’s conclusions. It finds a localized area of brittleness in HAZ III, which is linked to a rise in carbide formation. The least hard zone in this area indicates a zone that is prone to failure. The study also identifies problems with porosity in the weld zone and suggests ways to address them, including better shielding gas and careful wire brush cleaning during interpass welding. These results help to improve the structural reliability of quenched and tempered steel in critical applications by optimizing the welding processes.