Effects of heat treatment on degradation, mechanical properties and cytocompatibility of Mg-1.5Zn-0.5Y-0.5Zr alloy

Abstract

ABSTRACT Effects of solution treatment (T4), solution and ageing treatment (T6) on the degradation behaviours, mechanical properties and cytocompatibility of the extruded Mg-1.5Zn-0.5Y-0.5Zr alloy were studied in this work. Microstructural characterisation including SEM and TEM observation, degradation behaviours, tensile experiment and cytocompatibility tests was carried out. It showed that the alloy after 500°C × 2 h and 12 h ageing treatment exhibited the best degradation resistance with the degradation rate of 0.11 ± 0.01 mm/y in Hank’s solution. Moreover, the fine and uniform distributed second phases after 12 h ageing treatment could effectively improve the ultimate tensile strength (UTS) of the alloy. Due to the low degradation rate, the alloy after 500°C solution and 12 h ageing treatment also exhibited good cytocompatibility with cell viability value of more than 90%. In essence, 500°C × 2 h and 12 h ageing was the best heat treatment practice for Mg-1.5Zn-0.5Y-0.5Zr alloy.