Mechanical Properties of Plasma-Sprayed Hydroxyapatite Coating after Post Heat Treatment: Effect of Residual Stress

摘要

Through the measurement results of the residual strains of Hydroxyapatite coatings (HACs) and the values of Young’s moduli, the initial vacuum heating treatment (<600°C) can release the compressive residual strain of HAC after plasma spraying, so enabling HACs to obtain the optimal bond strength at the heating temperature of 500~600°C. Nonetheless, the post-vacuum heating temperature higher than 600°C led to the deterioration of the bond strength of HA/Tisubstrate. With the increasing temperature, the increased compressive residual strain will weaken the interfacial adhesive force of coating to substrate, resulting in the lower bond strength with higher temperature. The results of this paper demonstrated that the proper temperature of postvacuum heating treatment improved effectively the bonding strength between HAC and Ti-alloy substrate.