Crack self-healing of phytic acid conversion coating on AZ31 magnesium alloy by heat treatment and the corrosion resistance
Crack self-healing of phytic acid conversion coating on AZ31 magnesium alloy by heat treatment and the corrosion resistance
复制标题
AZ31镁合金植酸转化膜热处理裂纹自修复及耐腐蚀性能
DOI：
10.1016/j.apsusc.2014.06.104
复制
发表时间：
2014-09-15
影响因子：
6.7
通讯作者：
Wu, Xiaodong
中科院分区：
文献类型：
--
作者：
Zhang, Ruiyue;Cai, Shu;Wu, Xiaodong
以AZ 31镁合金为基体，采用植酸溶液浸渍法制备了植酸转化膜。研究了150 ℃ ~ 400 ℃热处理对涂层化学成分和裂纹愈合的影响，并通过电化学测试研究了涂层在模拟体液中的耐蚀性。结果表明，随着热处理温度的升高，转化膜表面裂纹逐渐愈合，提高了镁合金的耐蚀性。在热处理过程中，由无定形植酸镁组成的转化膜转化为结晶Mg 2 P2 O 7。同时，大分子复合物转变为小分子有机结构，并伴随着体积的增加，导致表面裂纹自愈合。在400 ℃热处理的涂层表现出优越的上级的表面完整性和耐腐蚀性，由于大量的Mg 2 P2 O 7结晶和裂纹愈合。由爱思唯尔公司出版
A phytic acid conversion coating was developed on AZ31 magnesium alloy by dipping the magnesium alloy into the phytic acid solution. The effects of heat treatment in the temperature range of 150 degrees C-400 degrees C on the chemical composition of the coatings and the crack healing were investigated, and the corrosion resistance of the coatings in simulated body fluid was studied by electrochemical measurements. The results showed that with the increase of the heat treatment temperature, the cracks on the surface of the conversion coating gradually healed up, that subsequently improved the corrosion resistance of these coated magnesium alloy. During the heat treatment process, the conversion coating composed of amorphous magnesium phytate was transformed to crystalline Mg2P2O7. Meanwhile, the macromolecular complex changed into small organic structure, and accompanied the increase of the volume, leading to the surface crack self-healing. The coating heat-treated at 400 degrees C exhibited superior surface integrity and corrosion resistance due to the great crystallization of Mg2P2O7 and crack healing. Published by Elsevier B.V.