论文期刊

A nanoplate-like -Al2O3 out-layered Al2O3-ZrO2 coating fabricated by micro-arc oxidation for hip joint prosthesis




作者: Lan Zhang, Yong Han
发表/完成日期: 2015-11-01
期刊名称: Applied Surface Science
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论文简介
A nanoplate-like a-Al2O3 out-layered Al2O3-ZrO2 coating was fabricated on Zr substrate by micro-arc oxidation (MAO). The structure, formation mechanism, anti-wear property and aging behavior of the coating were explored. The obtained results show that the coating is composed of Al2O3 and ZrO2; the amount and crystallinity of Al2O3 increase gradually from inner layer to the coating surface; monoclinic ZrO2 (m-ZrO2) and tetragonal ZrO2 (t-ZrO2) are both present in the coating, and the ratio of t-ZrO2/m-ZrO2 increases with closing to the coating surface by a “constraint” mechanism of Al2O3; the coating surface mainly consists of nanoplate-like a-Al2O3, and a small amount of nanocrystallized m- and t-ZrO2. The superimposition ofa-Al2O3 growth unit on {0001} face should be prohibited by PO43- during the MAO process, resulting in the formation of nanoplate-like a-Al2O3 on the coating surface. Compared with pure Zr, the coating shows noticeable improvement in wear-resistance. For aging behavior, although more t-ZrO2 in the coating is transformed to m-ZrO2 with increasing aging time, wear loss increases slightly. It indicates that the nanoplate-like a-Al2O3 out-layered Al2O3-ZrO2 is a potential coating for articular head replacement.