Abstract
The industry’s pursuit of clean technologies and materials amidst growing concerns about climate change underscores the significance of innovative welding processes. The utilization of TRIP 800 steel, renowned for its transformation-induced plasticity, highlights the endeavor towards enhancing energy efficiency and safety in the automotive sector. Nevertheless, welding this material poses significant challenges, particularly in the formation of martensitic regions in the weld zone, potentially resulting in reduced ductility and increased brittleness. Additionally, the thermal cycle involved in the welding process may induce unfavorable microstructural changes, affecting the overall integrity of the welded joint. Despite these challenges, FSSW emerges as a promising alternative to traditional welding processes, offering advantages such as reduced energy consumption and enhanced mechanical properties. This study aimed to investigate welds in TRIP 800 steel sheets through the Friction Stir Spot Welding (FSSW) process after deformation, thereby reflecting broader applications beyond vehicle manufacturing. The interaction of factors, including time and rotation speed, was examined at various levels for microstructural characterization, tensile and microhardness tests, showcasing the versatility and potential of the FSSW process. The analysis of welded joints revealed distinct regions such as the stir zone, thermomechanically affected zone, thermally affected zone, and base metal, illustrating the complexity and precision of modern welding techniques. Notably, the study delved into the microstructures of the affected zones, elucidating their pivotal role in influencing mechanical behavior under load conditions until failure. This investigation contributes to the ongoing quest for innovative solutions in vehicle manufacturing, emphasizing the importance of understanding welding processes and material properties in achieving sustainability and performance goals.