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采用机械合金化 ,随后在 6 2 0℃ ,5 8MPa下热压制备了致密的块体亚稳态纳米晶Ag5 0Ni5 0合金 ,用X射线衍射仪、扫描电镜和透射电镜研究了其组织结构。晶格常数的精确测定结果表明 ,球磨 2 0 0h后Ag在Ni中固溶度为 4.96 %± 0 .2 1%(摩尔分数 ) ,Ni在Ag中固溶度为 0 .84%± 0 .30 %(摩尔分数 ) ,热压以后仍具有过饱和固溶度 ,Ag在Ni中为0 .45 %± 0 .11%(摩尔分数 ) ,在相近温度下稳定化处理后进一步脱溶。6 0 0～ 70 0℃时Ag在Ni中固溶度为 (0 .2 1～ 0 .2 4) %± 0 .11%(摩尔分数 ) ,Ni在Ag中固溶度小于 0 .1%(摩尔分数 )。机械合金化粉末的晶粒度约为 6nm ,热压后长大至 40～ 6 0nm ,退火后又长大至 10 0～ 110nm。探讨了晶粒度与内应力同时作用下X射线衍射峰的展宽问题和纳米晶结构对快速致密化的作用
The mechanical properties of Ag 5 O 5 Ni 5 O 5 alloy were investigated by mechanical alloying followed by hot pressing at 520 ℃ and 5 8MPa. The microstructure of the nanostructured Ag 5 0Ni 5 0 alloy was characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The accurate determination of the lattice constant shows that the solid solubility of Ag in Ni is 4.96% ± 0.21% (molar fraction) after 200 h milling, and the solid solubility of Ni in Ag is 0.84% ± 0. 30% (mole fraction), after supersaturation still supersaturated solid solubility, Ag in Ni 0.45% ± 0.11% (mole fraction), at similar temperatures after further stabilization of the desolventizing. The solid solubility of Ag in Ni is between (0 .21-0.24)% ± 0.11% (molar fraction) at 600 ~ 70 0 ℃. The solubility of Ni in Ag is less than 0.1% (Mole fraction). The mechanical alloying powder has a grain size of about 6 nm, grows to 40-600 nm after hot pressing, and grows to 100-110 nm after annealing. The broadening of the X-ray diffraction peaks and the effect of the nanocrystalline structure on the rapid densification are discussed under the simultaneous action of grain size and internal stress