Friction stir-assisted cladding: Solid-state recycling of machine shop scrap for sustainable metal production

Abstract

The manufacturing industry, a cornerstone of modern economies, generates a substantial amount of waste in the form of manufacturing chips, which often end up as discarded byproducts. This waste not only poses environmental hazards but also represents a missed opportunity for resource efficiency and cost savings. This article explores the innovative use of friction stirassisted cladding (FS-AC) as a sustainable and cost-effective solution for repurposing aluminum chips on a steel substrate without melting the material. The study investigates the mechanism of the FS-AC process, highlighting the conversion of metallic swarf into a feedstock material for cladding without entailing costly clad materials. Metallographic analysis demonstrates a uniformly clad layer with an average thickness of 0.95 mm. The study addresses challenges related to bonding at the clad layer-substrate interface and proposes further advanced characterization studies for diffusion analysis and coating-substrate bond strength. In conclusion, the FS-AC process presents a valuable method for recycling machine shop floor scrap, transforming it into useful feedstock material for cladding purposes, and that too in an energy-efficient manner. This proposed approach has promising potential for processing different material combinations for additive manufacturing and exploring functionally graded material development using metallic swarf.