Novel microstructures from severely deformed Al–Ti alloys created by chip formation in machining

摘要

We present some consequences of Severe Plastic Deformation (SPD) of Al–Ti alloys by chip formation in machining that can enable opportunities for creating novel microstructures. Chips cut from Al-6wt%Ti are composed of a refined dispersion of the fragmented remains of a hitherto coarse Al₃Ti embedded in a nanostructured matrix. This multi-phase nanostructured chip material demonstrates considerable resistance to coarsening owing to the thermally stable dispersion of ultra-fine Al₃Ti dispersions and thus has promise in structural alloy applications. Furthermore, the Al–Ti machining chips are shown to possess excellent grain refining characteristics, leading to microstructurally refined and homogeneous Al alloy castings. This realization enables a low-cost route for enhancing the efficiency of the grain refiner master alloy systems by exploiting SPD during chip formation.