材料期刊网

在Ge或Si和杂质元素组成的二元系中,及Au-Bi,Au-Tl,Ag-Bi,Ag-Pb,Ag-Tl(后一元素表示杂质)中,发现杂质元素分布系数K_B的对数和液相线上组分A的开方浓度。x_(A,L)~(1/2)间有直线关系。据此外推求得的Ge或Si(IV族)中熔点下分布系数K_B~o和实验结果相当符合,也求得了Au,Ag,Cu(Ⅰ族),Mg(Ⅱ族),Al(Ⅲ族)中某些杂质的K_B~o。在这些系统中,发现如Fischler在Ge或Si中所指出的那样,K_B~o和杂质元素的最大固溶度之间也有简单的经验关系。

A linear relation has been obtained between the logarithm of the distribution co-efficient of impurities logK_B and the square root of liquidus composition for componentA x_(A, L)~(1/2). in binary systems of Ge or Si with impurities. This relationship hasbeen found to be also applicable to Au-Bi, Au-Tl, Ag-Bi, Ag-Pb and Ag-Tl systems,where the second element represents the impurity. The distribution coefficients at themelting point (K_B~o) of impurities in Ge or Si obtained by extrapolating to zero concentra-tion are in reasonable agreement with the experimental values. Besides, the values K_B~oof certain impurities in Au, Ag, Cu (from group I), Mg (from group II) and Al (fromgroup III) have been calculated. It is shown that in these systems a simple correlationexists between K_B~o and the maximum molar solid solubility of impurities, just like thatfound earlier by Fischler in the binary systems of Ge or Si.