第二相对Al-Zn-Sn-Ga-Mg合金腐蚀行为的影响  

Influence of second phase on corrosion behavior of Al-Zn-Sn-Ga-Mg alloy

作　　者：贺俊光[1] 文九巴[1] 周旭东[1] 

机构地区：[1]河南科技大学材料科学与工程学院,洛阳471003

出　　处：《中国有色金属学报》2013年第3期628-634,共7页The Chinese Journal of Nonferrous Metals

基　　金：河南省科技创新杰出人才计划资助项目(094200510019);河南省自然科学基金资助项目(092300410132)

摘　　要：通过分析Al-7Zn-0.1Sn-0.015Ga-2Mg阳极合金中的第二相及其腐蚀特性,研究第二相对该合金腐蚀行为的影响。结果表明:Al-7Zn-0.1Sn-0.015Ga-2Mg阳极合金中的第二相主要为球状和棒状的MgZn2相。MgZn2相的腐蚀电位较α(Al)基体的负,腐蚀电流密度较高且极化电阻较小。MgZn2相对于α(Al)基体为阳极相,其在3.5%NaCl溶液中与α(Al)基体组成腐蚀微电池,引起MgZn2相自身优先溶解,进而引发合金全面溶解。Influence of the second phase on the corrosion behavior of AI-7Zn-0.1 Sn-0.015Ga-2Mg alloy was investigated through the analysis of the second phase and its corrosion characteristics in A1-7Zn-0.1Sn-0.015Ga-2Mg alloy. The results show that the second phases in A1-7Zn-0.1Sn-0.015Ga-2Mg alloy mainly are MgZn2 particles with spherical and rod-like. MgZn2 has a more negative corrosion potential, a higher corrosion current density and a smaller polarization resistance than a（A1） matrix. The MgZn2 particles are the anodic phase relative to a（Al） matrix, they form many micro-corrosion cells with a（A1） matrix in 3.5% NaC1 solution, which lead to the anodic self-dissolution of MgZn2 particles preferential, and resulting in the whole dissolution process of the aluminum sacrificial anode.

关 键 词：铝合金 牺牲阳极 第二相 腐蚀行为 

分 类 号：TG174.41[金属学及工艺—金属表面处理]