评述了Ag与RE金属相互作用与合金化行为.随着镧系元素原子序数增大,RE在Ag中固溶度增大;RE与Ag原子半径差(Δr/rAg)是影响RE在Ag中固溶度的主要因素:当Δr/rAg>26%时,Cmax很小或为零;当Δr/rAg<26%时,Cmax=A-B(logΔr/rAg-1).在Ag-RE系中出现(RE∶Ag)1∶5、2∶9、1∶4、14∶51、2∶7、1∶3、1∶2、1∶1、3∶2和5∶2十种化学计量化合物和19种晶体结构,4个共晶系10种共晶反应和8种包晶反应.根据简约温度图,评述了简约共晶温度和中间相简约转变温度与RE原子序数的关系:随着RE原子序数增大,简约温度有规律下降,但在Ce、Eu和Yb上出现反常高值.简约共晶温度(Teu/TAg)与RE原子半径的关系符合由Au-RE系建立的判据:Teu/TAg随RE原子半径增大而线性降低,但当rRE大于0.175nm(原子半径差大于21%)后Teu/TAg基本保持不变.在Ag-RE系中,Eu和Yb取2价态,其它RE取3价态.
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