Significance of in-situ dry-ice blasting on the microstructure, crystallinity and bonding strength of plasma-sprayed hydroxyapatite coatings
Significance of in-situ dry-ice blasting on the microstructure, crystallinity and bonding strength of plasma-sprayed hydroxyapatite coatings
复制标题
原位干冰喷射对等离子喷涂羟基磷灰石涂层微观结构、结晶度和结合强度的意义
DOI：
10.1016/j.jmbbm.2017.03.003
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发表时间：
2017
影响因子：
3.9
通讯作者：
Hanlin Liao
中科院分区：
文献类型：
--
作者：
Shujuan Dong;Jinyan Zeng;Lifen Li;Junbin Sun;Xiong Yang;Hanlin Liao
为了获得长期稳定的高结晶度羟基磷灰石（HA）涂层，在临床应用中，通常将粗粉注入低能量等离子体中。然而，部分熔融颗粒堆积的HA涂层通常具有较高的孔隙率和较差的力学性能，尤其是较差的结合强度。本文利用干冰喷射的淬火和机械冲击作用，在等离子喷涂过程中原位加入干冰喷射，以改善HA涂层的微观结构和结合强度。此外，原位干冰喷射对等离子喷涂HA涂层的相组成和结晶度的影响进行了研究。结果表明，干冰喷射对未熔颗粒和飞溅碎片的清理作用使等离子喷涂HA涂层的孔隙率显著降低，结合强度明显提高。采用等离子喷涂和干冰喷射相结合的方法制备的HA涂层具有球状孔隙最少但微裂纹明显的折衷结构。CaO相的消失和结晶度的增加也源于干冰喷射的应用。
To obtain hydroxyapatite (HA) coatings with high crystallinity which have long-term stability in clinical applications, coarse powders were usually injected to less energetic plasma. However, the HA coatings accumulated by partly melted particles usually have high porosity and poor mechanical properties, especially poor bonding strength. In this work, by profiting its quenching and mechanical impact, dry-ice blasting was in-situ employed during plasma spray process to improve the microstructure characterization and bonding strength of HA coatings. In addition, the influence of in-situ dry-ice blasting on the phase composition and crystallinity of plasma-sprayed HA coatings was investigated. The results show that a significant reduction of porosity and an apparent increase in bonding strength are revealed in plasma-sprayed HA coatings due to the cleaning effect of dry-ice blasting on the convex unmelted particles and splashing fragments. HA coatings prepared by the combination process of plasma spraying and dry-ice blasting have a compromise structure with minimum globular pores but with pronounced microcracks. The disappearance of CaO phase and the increase in crystallinity also derive from the application of dry-ice blasting.