Numerical simulation of solidification process and microstructure evolution of single crystal investment castings

被引：0

作者：

Liang, ZJ ^{[1
]}

Li, JR ^{[1
]}

Liu, BC ^{[1
]}

Xu, QY ^{[1
]}

Yuan, HL ^{[1
]}

Liu, SH ^{[1
]}

机构：

[1] Tsing Hua Univ, Dept Mech Engn, Beijing 100084, Peoples R China

来源：

MULTIPHASE PHENOMENA AND CFD MODELING AND SIMULATION IN MATERIALS PROCESSES | 2004年

关键词：

single crystal; investment casting; microstructure evolution; solidification; numerical simulation;

D O I：

暂无

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Single crystal solidification of turbine blades is a key technology for the production of reliable and high efficiency gas turbines. The solidification process of single crystal investment castings causes a number of problems that have to be solved such as the increase of casting defects and complexity of production process. Computer modeling and simulation is helpful to predict the defects and improve the process design. In the paper, a mathematical model for three dimensional simulation of solidification and single crystal growth of investment castings was developed based on CA, mechanism of crystal growth and basic transfer equations such as heat, mass transfer equations. Many factors including constitutional undercooling, curvature undercooling and anisotropy, which had vital influences on microstructure evolution, were considered in the model. Temperature, crystal growth interface and structure defects of investment castings of single crystal superalloy were investigated at withdrawal rates of 4.5mm/min and 7mm/min. Simulated results showed that microstructure evolution and structure defects were predicted reasonably and calculated results were coincident with experimental ones. The study indicated that three dimensional solidification simulation technique is a powerful tool for understanding the fundamental of solidification and the formation of structure defects in single crystal investment castings and finally for optimizing process design.

引用

页码：227 / 234

页数：8