Ti6Al4V钛合金表面Al2O3颗粒改性微弧氧化涂层制备及性能

Preparation and property of a modified micro-arc oxidation coating using Al2O3 particles on Ti6Al4V

摘要:

微弧氧化技术是一门新的表面处理技术,在很多领域有着广泛的应用前景,但其结构受限于电解液成分。本文通过在磷酸盐电解液中加入Al2O3陶瓷颗粒,使得在Ti6Al4V钛合金表面的微弧氧化涂层结构和性能得到改性。涂层的结构和性能通过扫描电镜和XRD衍射仪进行表征和测试,涂层的抗高温氧化性能和热震性能通过高温热循环氧化试验和热震试验进行测试。结果表明,通过在电解液中添加Al2O3陶瓷颗粒,涂层由Al2TiO5 and TiO2组成,涂层更为致密,表现出更为优异的抗高温氧化和热震性能。电解液中游动的Al2O3陶瓷颗粒在微弧氧化过程中被吸入到样品表面并进入涂层,涂层的结构和性能得到改性。

Abstract:

Micro-arc oxidation is a new surface treatment method, but the structure of the micro-arc oxidation coating is limited to the electrolyte composition. In this paper the micro-arc oxidation coating on Ti6Al4V alloy was modified by addition of micro- Al₂O₃ particles to a sodium phosphate solution. The coating structure and phase was characterized by scanning electron microscopy and X-ray diffraction, and the oxidation resistance and thermal shock properties of the coating were investigated. Results showed that a coating denser than the original coating was produced. This new coating was composed of Al₂TiO₅ and TiO₂. The oxidation resistance and thermal shock property of the coating improved with addition of Al₂O₃ particles to the electrolyte relative to the sample prepared without the particles in the electrolyte. Moving Al₂O₃ particles were adsorbed on the coating surface and penetrated through it. As a result, the phase structure and properties of the original coating were modified.