Machinability of cupola slag incorporated LM11 matrix composites in turning: Surface roughness and MRR analysis

Abstract

This study explores the potential of using cupola slag, a byproduct of cast iron production, as reinforcement in Al-4.5-Cu (LM11) matrix composites. The composites were fabricated using a low-cost stir casting method, with varying percentages of cupola slag (0 %, 3 %, 5 %, and 7 %) added to the matrix. The cast composites were then evaluated based on their microstructure, microhardness density and machinability indices, including material removal rate, surface roughness, chip thickness and chip analysis during dry turning. A full factorial design of experimentation was employed to determine the effects of different process inputs on machinability, with feed, spindle speed, and weight percentage of cupola slag as the variables. The results showed that 7 wt% cupola slag incorporation improved machinability, but beyond this percentage, the casting became unstable due to reduced wettability. This study offers valuable insights into the machinability of cupola slag embedded cast composites and the influence of different process inputs on their machinability by using a low-cost stir casting method and an unwanted byproduct as reinforcement, this approach offers a novel and sustainable alternative for the reinforcement of metal matrix composites.