Analysis of crystallographic orientation influence on thermal fatigue with delay of the single-crystal corset sample by means of thermo-elasto-visco-plastic finite-element modeling

A V Savikovskii ,А С Семенов ,Л Б Гецов

doi:10.1051/matecconf/201824510006

Abstract

The influence of a delay time at the maximum temperature on the number of cycles before the macrocrack initiation for two thermal loading programs was investigated for single-crystal nickel-based superalloy VZhM4. An analytic approximation of a delay time influence was proposed. Comparison of the computational results and analytic formula on the basis of constitutive equations with the experimental data was performed for various single-crystal nickel-based superalloys and showed a good accuracy. The influence of crystallographic orientation of the corset sample on the thermal fatigue durability with delay times was investigated for various thermal loading programs and single-crystal nickel-based superalloys.

Highlights

Single-crystal nickel based superalloys [1, 2] are promising used for production of gas turbine engines (GTE) [3]
Influence of crystallographic orientation (CGO) on thermal fatigue strength for superalloys VZhM4 for two temperature modes is presented in fig. 9
Further improvement of the accuracy of thermal fatigue durability calculations with delays can be achieved by considering more complex creep models [25, 26] and taking into account the rafting process [27] at high temperatures

Summary

Introduction

Single-crystal nickel based superalloys [1, 2] are promising used for production of gas turbine engines (GTE) [3]. These materials have a pronounced anisotropy and temperature dependence of properties. For the investigation of thermal fatigue durability under a wide range of temperatures with and without delay times the experiments are carried out on different types of samples, including corset (plane) specimen [4] on the installation developed in NPO CKTI [6] (see Fig. 1). The fixing of sample under heating leads to the high stress level and inelastic strain appearance. The FE simulation is required for the computation of inhomogeneous stress and inelastic strain fields

Objectives

Methods

Results

Conclusion