Open AccessStudy on the electrical parameter variation during microarc oxidation of alumini um alloys
Author(s) -
Huibin Wu,
Long Bei-hong,
Lyu Xian-Yi,
Jianbo Wang,
Jin Zeng-Sun
Publication year - 2005
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.54.1697
Subject(s) - materials science , scanning electron microscope , electrical resistance and conductance , aluminium , composite material , analytical chemistry (journal) , chemistry , chromatography
The variation of electrical parameters during microarc oxidation(MAO) of aluminium alloys at constant voltage has been studied by means of a laboratory-made data acquisition system. Experimental results show that the variations of the cath odic and anodic current amplitude and effective working current in an electrical loop with the duration of treatment show obviously five stages, and the variati ons of dynamic positive resistance and the rate of change of resistance in coati ngs also show different stages, while the variations of dynamic negative resista nce and the rate of change of resistance with oxidation time are not evident. Du ring the MAO process, the dynamic positive resistance is always not equal to the negative resistance, and the former is generally greater than the latter in gen eral. Scanning electron microscopy analysis shows that the surface morphology of MAO coatings is macro-porous and its variations with treatment time are in ste ps.