Comparison of Mechanical Properties and Microstructure of Hot-Rolled Mg-Gd Alloys Between 95% Reduction and 80% Reduction as Degradable Implants

Mg-Gd alloy as a dissolvable implantable material is of interest to many researchers. However, mechanical properties will continue to be improved to obtain optimum results such as good strength, ductility, and hardness. This paper aims, to present a comparison of the mechanical properties of two different treatments between hot rolling with 95% reduction and 80% reduction, so that to find optimized results for Mg-Gd alloy as a soluble implant material. Rolling temperatures varied from 400, 450, 500 and 550°C. Hot rolling of the Mg-Gd alloy was performed unidirectionally, with the reduction varied. The results of these two tests show that hot rolling with 95% reduction exhibits better mechanical properties than hot rolling with 80% reduction. These results are closely related to the microstructure results, where hot rolling with 95% reduction produces a finer grain size than hot rolling with 80% reduction, which is an average of 50 µm, while 80% reduction is above 100 µm on average. While the hardness obtained is around 40-60 HVN for a reduction of 95 % is almost the same as a reduction of 80 %. For the highest strength reached 195 MPa for a reduction of 95 %, while the 80% reduction only reached 165 MPa. Overall, Mg-Gd alloy with hot rolling through higher reduction can improve the mechanical properties and hardness of Mg-Gd alloy as an easy implant material.