显微组织和腐蚀行为的影响
(1. 湖南城市学院 物理与电信工程系，益阳 413000；2. 湘潭大学 材料与光电物理学院，湘潭411105)
摘 要: 采用电弧熔炼铜模吸铸法制备La62.0Al15.7(Cu, Ni)22.3非晶合金，在室温下对该非晶合金进行高压处理(压力为3~5 GPa)，研究高压处理对非晶合金显微组织的影响；并对非晶合金在3.5%NaCl溶液中的电化学性能进行测试。结果表明：室温下的高压处理使该非晶合金发生结构驰豫，从而导致其玻璃转变温度、第一晶化温度及驰豫激活体积发生改变；高压处理后，非晶合金的自腐蚀电位增加，自腐蚀电流密度减小，临界点蚀电位下降，因此，高压处理提高该了非晶合金的抗均匀腐蚀能力，但降低了其抗点蚀的能力。
关键字: 非晶合金；高压处理；电化学腐蚀
corrosion behavior of La62.0Al15.7(Cu, Ni)22.3 amorphous alloy
（1. Department of Physics and Telecommunication Engineering, Hunan City University, Yiyang 413000, China;
2. Faculty of Material and Photoelectronic Physics, Xiangtan University, Xiangtan 411105, China）
Abstract:The La62.0Al15.7(Cu, Ni)22.3 amorphous alloy was prepared by the injection of liquid alloy into a copper mould. The alloy was treated under high pressures in the range of 3.0−5.0 GPa at room temperature, and the effects of the high pressure treatment on the microstructure of alloys were investigated. The corrosion behavior of the alloy electrolyte was measured in 3.5% NaCl by the electrochemical method. The results indicate that the high pressure treatment at room temperature causes the structural relaxation of alloy, which results in the changes of the glass transition temperature, the first crystallization temperature and the relaxation activation volume of the alloy. Compared with the as-cast alloy, the alloy treated by high pressure exhibits high self-corrosion potential, low self-corrosion current and low critical pitting potential. This implies that high pressure treatment promotes the uniform corrosion resistance, but deteriorates the pitting resistance of the alloy.
Key words: amorphous alloy; high pressure treatment; electrochemical corrosion
