Application of a novel finite element method to design of splices in a fiber metal subjected to coupled thermo-mechanical loading

摘要

The splice concept has been developed in fiber metal laminates (FMLs) due to the limited dimensions of pretreatment facility, the autoclave curing facility and C-scan facility. Failure always initiates in the splice opening between the metal splice edges before delamination occurs in the loading direction. In this paper, a novel finite element method for obtaining stress intensities is introduced in the estimation of the failure strength of splices in FMLs. A super wedge tip element for application to bi-material wedge is developed utilizing the numerical stress and displacement field solutions based on an ad hoc finite element eigenanalysis method, from which singular stress fields near apex of arbitrary bi-material wedges under coupled thermo-mechanical loading can be obtained. Failure of double spliced FMLs with varying spliced width and fiber-layer thickness were investigated, and fracture criterion based on stress intensity factors are presented to predict splice failure.