Thermo-mechanical fatigue cracks on the turbine housing of turbochargers are often observed in currently developed gasoline engines for them to adopt lightness and higher performance levels. Maximum gas temperatures of gasoline engines usually exceed 950℃ under engine test conditions. In order to predict thermo-mechanical failures by simulation method, it is essential to consider temperature-dependent inelastic materials and inhomogeneous temperature distributions undergoing thermal cyclic loads. This paper presented the analytical methods to calculate thermal stresses and plastic strain ranges for the prediction of fatigue failures on the basis of motoring test mode, which is commonly used for accelerated engine endurance test. The analysis results showed that the localized critical regions with large plastic strains coincided well with crack locations from a thermal shock test.

Abstract
 1. 서론
 2. 주기하중 하의 재료의 거동
 3. 해석결과 및 고찰
  3.1 터빈하우징 유한요소모델
  3.2 터빈하우징의 온도분포
  3.3 열응력 해석
 4. 결론
 References

• 최복록(강릉원주대학교) | B. L. CHOI