采用电化学方法、化学分析和表面分析技术,系统研究了Cu-20Zr双相铸态合金和磁控溅射Cu-20Zr纳米薄膜在HCl溶液中的脱合金腐蚀规律.对Cu-20Zr双相铸态合金的研究表明,铸态Cu-20Zr合金中的双相为富Zr的Cu51Zr14相,及Cu与CugZr2的共晶组织;在低阳极极化电位条件下,Cu51Z14相因富含活性组元Zr而优先溶解,说明双相合金的溶解行为首先决定于合金的相及其本身的活性.对溅射Cu-20Zr纳米薄膜腐蚀规律的研究表明,在不同电极电位下,薄膜中各元素的溶解规律不同.当电极电位低于Cu的标准电极电位时,材料的腐蚀以富Zr相中Zr组元的优先溶解为主;但当电极电位高于Cu的标准电极电位后,薄膜中Cu、Zr元素同时溶解;随后,由于Cu2^+与溶液中的Cl-反应,生成氯化铜或氯化亚铜腐蚀产物覆盖于薄膜表面,使Cu的溶解过程受到抑制,但Zr元素却仍然随电极电位的增加而快速溶解.
The dealloying mechanism of the duplex - phase Cu - 20Zr cast alloy and sputtered Cu - 20Zr film in hydrochloric acid solution was investigated using the electrochemical methods, chemical and surface analysis techniques. Results showed the duplex - phase in cast Cu - 20Zr alloy is composed by two phases, one is the Zr - rich Cu51Zr14 phase, the another is the eutectoid of the Cu and Cu9Zr2 phase. The rich - Zr Cu51Zr14 phase selectively dissolves owing to its more reactivity at the low anodic potential, which illustrates the dissolution mechanism of the Cu - 20Zr alloy is decided by the stability of the microstructure. The study of the corrosion rules of the sputtered Cu - 20Zr film shows further that the dissolution process of each element is different at the different polarized potential. When the potential is lower than the redox of Cu/Cu^2+, the dissolution of Zr atoms is the main process;when the potential is higher than the redox of Cu/ Cu^2+, Zr and Cu atoms in the film simultaneously dissolve, and the dissolution rate of Cu atoms is higher than that of Zr atoms. Subsequently, Cu ions react with CI ions in the electrolyte, and form the corrosion products of Cu ( Ⅰ ) and Cu ( Ⅱ ) complex compounds. These corrosion products covered the surface of the film, retarded the dissolution of Cu atoms. Zr atoms still dissolve continually with increasing the potential.