镁合金微弧氧化过程中熄弧方式对膜层性能的影响

Study of Flameout in the Course of Micro-arc Oxidation of Magnesium Alloy

在镁合金微弧氧化过程中存在一种气体持续燃烧,造成工件失效、报废的现象。为了解决这一问题进行了氧化过程中电弧控制的研究。自然熄弧和强制熄弧是电弧熄灭的两种方式,比较了两种电弧的现象,并讨论了两种熄弧状态下得到的微弧氧化陶瓷层的性能。结果表明:自然熄弧状态下得到的陶瓷膜粗糙,表面有孔洞,导致工件失效;强制熄弧状态得到的膜层表面光滑,陶瓷膜与基体结合紧密。

Persistent gas combustion in the course of micro-arc oxidation on magnesium caused work pieces lapse or scraps. To settle this problem, we study the arc control method during the micro-arc oxidation. There are two flameout modes, one is nature, the other is force flameout. Nature flameout and force flameout are characterized by arc shape, physical model, circuit, pulse waveform. The results show that the film is coarseness, such as ＂holes＂ and ＂canyons＂ under nature flameout while the film is smooth, and oxide film combined tightly with ceramic film. Force flameout has the advantage of controlling film destroyed compared with nature flameout.