价电子浓度对B2及其超结构相的晶体结构和性能的影响

The present project aims at revealing the structural and property characteristics of the B2-based approximants of quasicrystals in the Al-base alloy systems from the viewpoint of the electron concentration judgment. We pointed out that the surface energy, coefficient of friction, microhardness, and DOS at the Fermi level all are related with the electron concentration e/a of the B2-bsed phases, regardless of their specific structures. When the e/a ratios of the phases approach that of the quasicrystal, their performances also approach those of the latter. As the main guide line of our research, the formation rules of quasicrystals are further refined and have guided us to locate the controversy composition of the stable Al-Ni-Fe quasicrystal. These rules also apply in bulk metallic glass forming systems, from which we put forward more general composition rules for alloy phases in multi-component systems. This project has been listed as a key project of NSFC in this year's NSFC guidebook.

本项目提示价电子浓度对Ｂ２及其超结构相的结构的性能的影响，尤其注重与准晶有关的结构和性能特征。拟以Ａｌ－Ｃｕ－（Ｍｎ，Ｆｅ）为对象，以价电子浓度为线索，利用取向关系理论来提示与准晶间的原子结构联系，测试晶体结构相同而价电子浓度各异的合金相的性能，从晶体结构和性能两个方面研究具有不同价电子浓度的Ｂ２及其超结构类拟相的特性。