金属间化合物强动力学效应对非晶转变的作用机制研究

项目名称： 金属间化合物强动力学效应对非晶转变的作用机制研究

项目编号： No.51271149

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 一般工业技术

项目作者： 王楠

作者单位： 西北工业大学

项目金额： 80万元

中文摘要： 含有金属间化合物相的合金易发生非晶转变，说明金属间化合物对非晶转变有其内在的作用机理。同固溶体相比，金属间化合物生长以二维形核或螺旋位错方式进行，动力学过冷度相对较大，所以含金属间化合物的共晶组织易获得深过冷，有可能导致非晶形成，但相关作用机制并不清楚。已有研究主要集中在金属间化合物熔体结构等对非晶转变的影响方面，而鲜有从动力学效应入手，因此无法揭示其对非晶转变的内在机理，亟待深入研究。本项目选用共晶相均为金属间化合物的Ni-Nb共晶合金和在毫米/秒速度条件下就发生"共晶-非晶"直接转变的Pd-Cu-Si合金，实现共晶到其它晶体形貌或非晶的转变，对于前者测量共晶转变的层片间距及生长速度，对于后者直接测量总过冷度，由此确定动力学过冷度，阐明其对扩散系数的影响规律，结合非晶合金体系扩散系数随过冷度增大显著减小的脆性特点，揭示强动力学效应对非晶相形成的作用机理，为设计新型的非晶合金提供理论依据。

中文关键词： 金属间化合物；动力学效应；扩散系数；非晶转变；

英文摘要： The alloys which can form glass phase or experience glass phase transition usually contain intermetallic compound, indicating that the intermetallic compound has its specific effect. Comapred with solid solution, the intermetallic compound grows in a manner of two-demension nucleation or screw dislocation. In this case, a high kinetic undercooling can be obtained, thus the total undercooling increases drastically. This maybe the reason why amorphourization occurs easily. The previous investigations on this aspect mainly focused on the effect of the complex liquid structure of the intermetallic compound melt on the glass formation and glass phase transition. However, few works consider the contribution of the kinetic undercooling. This project will investigate the intrinsic mechanisms of the effect of the intermetallic compound from the point of view of the kinetic effect. For this purpose, Ni-Nb and Pd-Cu-Si systems will be selected as the research objects. The former alloy, both of the two eutetic phases are intermetallic compounds, has been reported to form glass phase during solidification. While the later alloy, which also contain the intermetallic compound phases, can experience a "eutectic-glass" direct transition at a velocity in the order of magnitue of mm/s. By using these two alloys, eutectic to othe

英文关键词： Intermetallic compound；Kinetic effect；Diffusion coefficient；Glass transition；