顯微組織和腐蝕行為的影響
(1. 湖南城市學(xué)院 物理與電信工程系,益陽 413000;2. 湘潭大學(xué) 材料與光電物理學(xué)院,湘潭411105)
摘 要: 采用電弧熔煉銅模吸鑄法制備La62.0Al15.7(Cu, Ni)22.3非晶合金,在室溫下對該非晶合金進(jìn)行高壓處理(壓力為3~5 GPa),研究高壓處理對非晶合金顯微組織的影響;并對非晶合金在3.5%NaCl溶液中的電化學(xué)性能進(jìn)行測試。結(jié)果表明:室溫下的高壓處理使該非晶合金發(fā)生結(jié)構(gòu)馳豫,從而導(dǎo)致其玻璃轉(zhuǎn)變溫度、第一晶化溫度及馳豫激活體積發(fā)生改變;高壓處理后,非晶合金的自腐蝕電位增加,自腐蝕電流密度減小,臨界點蝕電位下降,因此,高壓處理提高該了非晶合金的抗均勻腐蝕能力,但降低了其抗點蝕的能力。
關(guān)鍵字: 非晶合金;高壓處理;電化學(xué)腐蝕
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


