Abstract
The formation of solidification cracks during fusion welding of high strength and highly alloyed wrought aluminum alloys has been a significant challenge over the years. Recently, using TiC-nanoparticle enhanced filler metals was found to be an effective way for solidification crack elimination during TIG welding of Al7075 sheets. However, the impact of welding parameters on weldability in the presence of nanoparticles is still not completely understood. Therefore, the present research investigates the weldability of 3-mm thick Al7075 sheets with TiC-nanoparticle enhanced filler metal (Al7075) during TIG welding. Two sets of welding parameters, leading to two different heat input levels, are studied. The experimental results show that the filler metal effectively eliminates solidification cracks in both joints. Microstructure evaluations show an equiaxed grain morphology in fusion zones with an average grain size of 19.6 ± 2.6 and 26.2 ± 1.5 μm for joints welded with low and high heat input, respectively. However, statistically similar microhardness values are measured on both joints, suggesting no significant impact of the grain size.