粉状锈生成的电化学腐蚀及价电子结构分析

The Electro-Chemical Corroding of Powder-Corrosion and the Analvsis of Valent-Electron Structure

用XFS、XRD、SEM方法检测不同地点出土,染有粉状锈的古青铜残片,剖面照片表明,粉状锈生成的途径之一是晶间腐蚀。参照平衡相图,制备出几种铜锡合金单相样品。将各相分别制成电极并测定其电板电位。结果证明高锡相较易被腐蚀,而亚稳态β′相比相邻的δ相更易被腐蚀,验证了晶间腐蚀是电化学腐蚀的结果。利用价电子结构分析方法分别对α相及δ相中各原子共价键上的电子对数进行计算,并利用单键键能求出各相中各类原子的能级及各合金相的能量。结果表明,在各类Cu-Sn合金中,含Sn量越高的相越不稳定,因此当δ相与α相构成原电池时,δ相首先被腐蚀。

Three ancient pronic fragments casted in different ages were unearthed from different locations. Methods of XFS, XRD and SEM are emploved to determine the element-content of al oys. and the compos(?) and (?)ture of the corrosion (PC) The sectionat photograph show that one of the paths to form PC from Cu-Sn alloy is the crystal-gap-corroding, which destroys the bronze relic more senousiy. According to the (?) phase-diagram of Cu-Sn, several singgle-phase bronze alloy sampies are casted, and the (?) prepared The electricalk potentials of those samples indicate that (?)-content phase to be corroded, (?) he β' phase.which belongs to (?) nerghbourmg δ phase (?) is the result of electro (?) corrosion. The analytical method (?) the electron couple numbers (?) oms and the energy (?) that in Cu-Sn (?) when a electro (?) formed with α and δ phases (?) preferen(?)ly