热处理对钛-生物玻璃涂层结合强度的影响

Effect of heat treatment on bonding strength of titantium-bioglass coatings

为了提高涂层与钛合金基体的结合强度,采用高速火焰喷涂方法,在Ti6Al4V钛合金基体表面喷涂不同比例的钛-生物玻璃复合涂层,喷涂后试样以5℃/min加热至700℃保温1h后随炉冷却。结果表明:高速火焰喷涂方法制备以钛为主粉,添加不同含量底釉生物玻璃(G),获得的涂层热处理前后结合强度范围在38～57MPa之间。涂层结合强度受喷涂粉体G添加量和热处理的影响。随着G添加量增加,结合强度升高,涂层经热处理后,结合强度略有下降。热处理释放了喷涂时产生的应力,使纯钛涂层裂纹加宽。而G的加入,与钛相互作用,发生浸润、扩散,涂层有再结晶和新相沿裂纹析出,起到修复裂纹的作用。

High velocity flame spraying technology was used to prepare titantium-bioglass composite coatings on the surface of Ti6Al4V substrate. The sprayed coatings were heated at 700℃ for lh, and then cooled in furnace. The effect of content of bottom glaze glass powder in the spraying powder and heat treatment on bonding strength of the coatings to substrate was studied. The results show that bonding strength of the coatings prepared using titantium powder and different proportion of glass powder ranges from 38MPa to 57MPa. The bonding strength of the coatings increases with the increase of the glass powder amount and decreases slightly after the coatings were heated due to cracking of the coatings by residual stress relieving. Cracks can be partly repaired in the titantium-bioglass coatings due to raction of glass with titantium to from new phases along cracks during heat treatment and thus the bonding strength of the coatings is improved.