Crack initiation life prediction method and crack initiation life prediction apparatus

摘要

PPROBLEM TO BE SOLVED: To provide an apparatus and method for predicting a crack initiation life to predict a crack initiation life in a short time in response to an element size when a distortion due to an applied load is analyzed by using a finite element method. PSOLUTION: An analysis model of a solder bonding section 8 in a vehicle connector 1 is divided by a mesh having the first predetermined element size (50 μm), and analyzed by using the finite element method. An average distortion εSBa50/SBdue to the applied load is obtained. With regard to the average distortion εSBa50/SB, a decrease constant αSB12.5/SBis calculated based on the second element size (12.5 μm) different from the first element size and obtained by previous and actual measurement and analysis. A decrease rate βSB50/SBis calculated by causing a predetermined correction parameter k corresponding to the first element size to act. The crack initiation life N is calculated by an expression for predicting lifetime using the decrease rate βSB50/SB. PCOPYRIGHT: (C)2011,JPO&INPIT