ATOMIC SCALE STUDY ON STRUCTURE AND BEHAVIOR OF ELEMENTS IN AMORPHOUS ALLOYS

点击翻译按钮获取中文摘要

In order to made clear the true picture of amorphous structure and the structure of nuclei of crystalline a study in an atomic scale has been made by atom-probe field-ion microscope. Alloys used in the present study are Pd-16at%Si and Pd-16at%Si-9at%Cu alloys whose electron diffraction patterns show halo ring in their solidified state.First, methods for statistical analyses of aton-probe data have been established. Next, the structure has been analyzed using the above methods. It is found that concentration fluctuation exists in the both alloys. It extends in the range of 8-24at%Si in the Pd-Si alloy and of 8-40at% Si in the Pd-Si-Cu alloy. Cu addition forces a range of concentration fluctuation to extend. The periodicity in the concentration fluctuation is found in the Pd-Si alloy, but not in the Pd-Si-Cu alloy. In the Pd-Si-Cu alloy Cu atoms form clusters with Pd and Si atoms of one to three. Such clusters may stabilize amorphous structure in the alloy that Cu atoms are added.The above analysis methods are quite effective to solve the atomic scale structure in alloy.