Performance and Prospects of Severe Plastic Deformation for Effective Biomedical Titanium Alloys

Abstract

A B S T R A C TApplication of severe plastic deformation (SPD) technology to process effective biomedical titanium alloys has shown promising results at laboratory scale. However, more research is still required before adopting this technology from laboratory scale to industrial scale production. This review presents performance and prospects of SPD for effective ultra-fine/nanograin structure-biomedical titanium alloys. Effective biomedical titanium alloys should have desired properties for the medical application. The properties include; high static and fatigue strengths, surface hardness for wear resistance, good ductility, corrosion resistance and biocompatibility. Based on current works reported in the literature, the review focused on; high-pressure torsion (HPT), equal channel angular pressing (ECAP), asymmetric rolling (AR), accumulative roll bonding (ARB) and repetitive corrugation and straightening (RCS). Overview of biomedical application of titanium alloys and desired material properties is presented. A detail discussion on the working principle, performance (e.g. induced strength, hardness, grain size and texture etc.) and material deformation homogeneity of each SPD method are presented. Also, prospects and challenges of each SPD method to be implemented at industrial scale for continuous and mass production are highlighted. The review concludes with the effectiveness of SPD processes, characteristics of processed samples and suggestion of future work for SPD to process effective biomedical titanium alloys at industrial scale.

Simulation of deformation behaviour of Aluminium 7075 during Equal Channel Angular Pressing (ECAP)

“…As alluded earlier, ECAP is used mostly for processing Al and its alloys, magnesium, copper and titanium and their alloys. Titanium materials are attractive for orthopaedic implants, and processing through ECAP enhances their strength as well as ductility for better performance [24], [25]. The flexibility of ECAP process makes it possible to process different shapes of specimens as compared to other SPD processes such as HPT.…”