An Integrated Analysis Method of Service Life Based on the 3D Heterogeneous Material Model with Casting Defects

Based on the heterogeneous material model, an integrated analysis method was introduced to predict the service life of propeller. The morphology and distribution characteristic of non-continuous defects (porosity & inclusion) were calculated and mapped into the finite element model by 3D-mapping algorithm, and the fatigue life was predicted based on the heterogeneous material model. In this paper, the coupling analysis of casting process and fatigue prediction of marine propeller was done. The results show that porosity and mass inclusions in blade roots of propeller form serious heterogeneous characteristics in those parts, which increased the maximum stress of the propeller and decreased its theoretical fatigue life by 1/2, indicating that the effect of non-continuous defects on the service performance of casting is notable and cannot be ignored. Based on the integrated analysis method, the inference of the pouring temperature and gating system on the service life of propeller was studied further. The integrated analysis method brings the influence of the casting defects into structural analysis and fatigue analysis, which can improve the accuracy of the fatigue life prediction significantly.