界面结构对基底异质形核特性及形核点分布影响的研究

项目名称： 界面结构对基底异质形核特性及形核点分布影响的研究

项目编号： No.51271213

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： 王猛

作者单位： 西北工业大学

项目金额： 80万元

中文摘要： 异质形核是材料制备过程中的主要形核方式，形核基底界面结构对新相异质形核过程具有重要影响，然而现有理论无法为此提供可用描述。申请人承担的青年科学基金已在基底形貌对异质形核影响机制方面获得了突破。本项目拟进一步考察非理想界面成分分布、晶格缺陷对异质形核的影响机理，分析不同条件下各因素对异质形核的影响权重，建立包含界面结构效应的非均质形核理论模型。拟开展的研究包括：基于粗糙界面润湿理论，考察基底成分对异质形核的影响；基于原子键合能量分析，研究基底微区成分对界面异质形核的影响；参照晶体生长机制理论描述，发展晶格缺陷对界面异质形核影响的理论模型；基于分子动力学方法研究不同条件下界面结构对异质形核的影响权重，描述多因素耦合作用下的异质形核规律；采用气液相变凝聚实验、液固相变形核实验对非理想基底表面异质形核分析提供验证。通过本项目的研究，可获得异质形核的更深入认识，为形核及凝固组织控制提供理论依据。

中文关键词： 非均质形核；基底结构；成分分布；分子动力学模拟；增材制造

英文摘要： Heterogeneous nucleation is the main means of nucleation in the preparation of materials by solidification processing. Research results have shown that the surface structures have important affections on heterogeneous nucleation of a new phase, but the phenomenon observed cannot be explained by the theories for heterogeneous nucleation. This project intends to investigate the influence mechanisms of the morphological characteristics, composition distributions, and lattice defects of a non-ideal substrate surface on the heterogeneous nucleation behaviors, evaluate the impact weight of different factors on the nucleation process, thus by including the effects of surface structure, constructing a theoretical description model for heterogeneous nucleation. Research works to be carried out are composed by: investigation on the surface composition on heterogeneous nucleation based on wetting theories for rough surfaces; investigation on the micro-composition on heterogeneous nucleation based on the atomic bonding energy analysis; describing the influence of interface lattice defects on heterogeneous nucleation with reference to the correspondent crystal growth theories; evaluation on the impact weight of factors on heterogeneous nucleation by molecular dynamic simulation; validation of the theoretical results by vapor

英文关键词： Heterogenoues nucleation；substrate structure；composition distribution；molecular dynamical simulation；additive manufacturing