新型钴基与Nb-Si基高温合金扩散动力学研究进展

Progress on the Diffusion Kinetics of Novel Co-based and Nb-Si-based Superalloys

扩散动力学信息是深入理解合金的相变机制、微观组织形成和演化机理的关键参数,也是实现新型钴基与Nb-Si基高温合金设计与研发必要的基础物性数据。首先,本文系统地归纳了高温合金中常见的合金化元素及其作用。随后,详细介绍了合金体系中自扩散系数与杂质扩散系数的机器学习计算方法、互扩散系数的实验测定方法以及示踪扩散系数的分子动力学计算方法,并介绍了本课题组在新型钴基与Nb-Si基高温合金多元扩散动力学数据库建立与完善方面的工作。最后,介绍了扩散动力学数据库在微观组织模拟、合金设计等领域的应用,并对扩散动力学数据库的完善及应用方面的发展进行了展望。

Data on diffusion kinetics of superalloys is crucial for gaining a thorough understanding of the mechanisms underlying the phase transition and microstructural evolution of superalloys.Further,it is the basis for the design and development of novel Co and Nb-Si-based superalloys.Herein,the common elements used in preparing superalloys and their corresponding functions are systematically summarized.In addition,the contribution of our research group in the establishment and improvement of databases on multicomponent diffusion kinetics of novel Co and Nb-Si-based superalloys is presented in detail.Furthermore,the machine learning method for self-diffusion coefficient and impurity diffusion coefficient,the experimental method for mutual diffusion coefficients,and the molecular dynamics method for tracer diffusion coefficients in the alloy systems are briefly discussed.In addition to providing a brief introduction of the applications of the databases in the simulation of microstructural evolution and alloy design,an outlook on the development of the databases on diffusion kinetics and related applications is presented.