A Succinct Method to Recycle WE43 Mg Alloys—From Wasted Chips to Consolidated Billets

Spark plasma sinteringSpark Plasma Sintering (SPS) and friction stir processingFriction Stir Processing (FSP) (FSP) were used to recycle waste WE43 Mg alloyMagnesium alloys (Mg alloys) turning them into consolidated billets. Billets were firstly produced from machining chips using SPS. Metallurgical bonding between chips was achieved during the process, yet large second phase network and pores were observed. Then FSPFriction Stir Processing (FSP) was further applied to refine microstructuresMicrostructure and remove pores confirmed by using electron backscattered diffractionElectron Backscatter Diffraction (EBSD) (EBSD) and 3D X-ray computed tomography (3D XCT). Most of the large second phases were refined to 100 nm. The average grain size was reduced from around 30 μm to around 1–3 μm. The hardness of FSPed material reached HV0.2 = 83.5, which is comparable against commercial extruded bar (T5, HV0.2 = 90.2).