论文部分内容阅读
采用水热法在Mg-3Nd-Zn-Zr合金表面制备无铬化学转化膜,研究了乙酸钠对膜层的影响.用场发射扫描电镜、X射线衍射、电化学测试方法分别研究了转化膜的形貌、相组成和耐蚀性能.结果表明,转化膜主要由球形颗粒状和层片状的Mg(OH)_2相、以及少量含Si的非晶化合物组成;适量的乙酸钠能促进球形颗粒状和层片状Mg(OH)_2发生团聚,缩小层片间隙,且对转化膜的生长速率影响小;膜层厚度可以达到约25μm,与基体结合牢固,耐蚀性得到明显提高.
Chromium-free chemical conversion coating was prepared on the surface of Mg-3Nd-Zn-Zr alloy by hydrothermal method, and the effect of sodium acetate on the coating was studied. The effects of sodium acetate on the coating were investigated by field emission scanning electron microscopy, X-ray diffraction and electrochemical measurements. Morphology, phase composition and corrosion resistance.The results show that the conversion coating mainly consists of spherical granular and lamellar Mg (OH) _2 phase, and a small amount of Si-containing amorphous compounds; an appropriate amount of sodium acetate can promote spherical particles Like and lamellar Mg (OH) 2 agglomeration, shrinking the lamellar gap, and the growth rate of the conversion film has little effect; film thickness can reach about 25μm, with a solid substrate, corrosion resistance has been significantly improved.