Effects of SiC nanoparticles on the dissimilar friction stir weldability of low-density polyethylene (LDPE) and AA7075 aluminum alloy

Abstract

Abstract Linear dissimilar friction stir welding (FSW) of metals and polymers displayed some attractive applications for crucial lightweight industries such as automotive. The substantial dissimilarity between these, unlike materials in terms of physical and mechanical properties, can affect the feasibility of this solid-state joining in an exceptionally challenging manner. In this article, an interesting approach is proposed to reduce such a tricky significant difference by strengthening the polymer during FSW treatment as the dissimilar weldment's weakest counterpart. A very soft polymer as low-density polyethylene (LDPE) and a relatively hard aluminum alloy as AA7075 were assessed under investigation for shifting the situation in terms of complexity toward the most critical state. Then, by pre-placing SiC nanoparticles inside the polymer side and afterward, they were introduced into the weld nugget during dissimilar materials mixing. The FSW processing parameters were optimized to reach a sound state of nanocomposite weld formation with superior mechanical performance. The cross-sectional investigation results announced the impact of SiC nanoparticles dispersion through the polymer matrix on dissimilar weldments' subsequent mechanical performance. The distribution of these reinforcing agents and their influence were considerably varied depending on the FSW processing parameters.