International Research Journal of Education and Technology

Double Pass Friction Stir Processing (DP-FSP) is a novel solid-state method utilized to improve microstructural and mechanical properties of material. The investigation in this article explores the influence of DP-FSP on Lead-Tin Bronze alloy, an extensively utilized bearing and sliding application material owing to its superior load-carrying capacity and wear resistance. The technique entails two successive friction stir processing passes in order to attain enhanced microstructure homogeneity, finer grain size, and enhanced mechanical properties. Effects of process parameters like tool rotation rate, traverse rate, and tool shape on the microstructure, hardness, and wear response of the alloy are evaluated systematically. Microstructural characterization by optical microscopy (OM) and scanning electron microscopy (SEM) indicates substantial grain refinement and uniform dispersion of lead particles post DP-FSP. The mechanical properties such as microhardness and tensile strength are measured, showing considerable improvement over the as-cast state. Wear resistance is also measured in pin-on-disk tests, exhibiting improved performance as a result of the fine-grained microstructure and homogeneous lead distribution. The findings show that DP-FSP is a reliable process for enhancing the overall performance of Lead-Tin Bronze alloys for better utilization in demanding industrial processes. The current research presents important information for the optimization of DP-FSP parameters for comparable copper-based alloys.

Keywords: Double Pass Friction Stir Processing, Lead-Tin Bronze, microstructure refinement, mechanical properties, wear resistance, grain refinement.