Current situation of research on test methods for elastic modulus and Poisson’s ratio of single crystal superalloys

Abstract

In view of the anisotropic characteristics of elastic constants of single crystal superalloys and other materials, this paper summarizes two main existing testing methods for measuring elastic moduli and Poisson’s ratio of single crystal superalloys: static method and dynamic method, and analyses the research status of elastic moduli and Poisson’s ratio of single crystal superalloys both at home and aboard. Also, the main problems and feasible solutions in current research both at home and abroad are summarized. And it is pointed out that there is no special testing standard for the elastic moduli and Poisson's ratio of single crystal superalloys. Compared with foreign countries, there is still an obvious gap in the testing and characterization technology in China, and effect of crystal orientation on elastic moduli and Poisson's ratio is often neglected in engineering applications. So it is necessary to estimate the influence of errors in measuring elastic constants of single crystal alloys by exiting testing standards. Meanwhile, this paper describes how to establish the quantitative relationship between crystal elastic moduli and arbitrary crystal orientation for single crystal superalloy DD6 through linear regression analysis of crystal orientation index and elastic moduli.

Keywords

• single crystal superalloys
• elastic modulus and poisson’s ratio
• static method
• dynamic method
• crystal orientation