| 摘要 |
PROBLEM TO BE SOLVED: To provide a life prediction device capable of accurately predicting a life of exhaust system component.SOLUTION: A constrained distortion &egr;r is obtained as a difference obtained by subtracting a thermal free distortion &egr;t which is a distortion of a free inflation by heat of a measurement object 5 from an actual distortion &egr;c which is the actual distortion of the measurement object 5. Next, a maximum value &egr;1max of a maximum main distortion and its generation angle &thetas; are obtained from the obtained constrained distortion &egr;r, and the maximum main distortion at the generation angle &thetas; is defined as a generation distortion &egr;&thetas;. Further, a generation stress &sgr; corresponding to the generation distortion &egr;&thetas; is obtained from the obtained generation distortion &egr;&thetas; and a temperature distribution T, and a relation between the generation distortion &egr;&thetas; and the generation stress &sgr; is prepared as a stress-distortion generation line diagram M2. In addition, a plastic distortion &egr;p is calculated from the prepared stress-distortion generation line diagram M2, and a fracture repetition frequency N1 is obtained from the plastic distortion &egr;p, and a life prediction is performed on the basis of the fracture repetition frequency N1. |
