Two types of experiments were designed and performed to evaluate the adhesive bond in metal foam composite sandwich structures. The tensile bond strength of face/core was determined through the flatwise tensile test ...Two types of experiments were designed and performed to evaluate the adhesive bond in metal foam composite sandwich structures. The tensile bond strength of face/core was determined through the flatwise tensile test （FWT）. The test results show that the interfacial peel strength is lower than the interlaminar peel strength in FWT test. The mode I interracial fracture toughness （GIC） of sandwich structures containing a pre-crack on the upper face/core interface is determined by modified cracked sandwich beam （MCSB） experiment. It is found that the crack propagates unsynchronously on the two side of the specimen and the propagation of interfacial debonding always stays on the face/core interface during the MCSB tests. In order to simulate the failure of metal foam composite sandwich structures, a computational model based on the Tsai-Hill failure criterion and cohesive zone model is used. By comparing with experiment results, it can be concluded that the computational model can validly simulate the interracial failure of metal foam composite sandwich structures with reasonable accuracy.展开更多
Shell structure is widely used in industrial applications, such as in machinery, aerospace, ship and building fields, as well as containers of pressurized chemicals or liquefied natural gas. Graphite/epoxy composites ...Shell structure is widely used in industrial applications, such as in machinery, aerospace, ship and building fields, as well as containers of pressurized chemicals or liquefied natural gas. Graphite/epoxy composites has advantages of light weight, high strength, corrosion resistance, low expansion, low shrin kage and are often used in the form of composite pressure vessel for various engineering applications. In this study, the stress distributions of composite pressure vessel were analyzed. The finite element code ANSYS was used in analysis, in which the eight-node element SHELL 281 was adopted. The internal pressure 20 MPa, as in container of compressed natural gas, was applied inside the symmetrical cross-ply graphite/epoxy composite pressure vessel. The finite element model was established with suitable mesh size and boundary conditions. The stress distributions are discussed for the composite pressure vessel, especially for the inner two layers at the junction of semis pherical part. The Tsai-Hill criterion was used to assess the failure of composite pressure vessel.展开更多
基金supported by the Major State Basic Research Development Program of China(973Program)under the contract No.2006CB601206
文摘Two types of experiments were designed and performed to evaluate the adhesive bond in metal foam composite sandwich structures. The tensile bond strength of face/core was determined through the flatwise tensile test （FWT）. The test results show that the interfacial peel strength is lower than the interlaminar peel strength in FWT test. The mode I interracial fracture toughness （GIC） of sandwich structures containing a pre-crack on the upper face/core interface is determined by modified cracked sandwich beam （MCSB） experiment. It is found that the crack propagates unsynchronously on the two side of the specimen and the propagation of interfacial debonding always stays on the face/core interface during the MCSB tests. In order to simulate the failure of metal foam composite sandwich structures, a computational model based on the Tsai-Hill failure criterion and cohesive zone model is used. By comparing with experiment results, it can be concluded that the computational model can validly simulate the interracial failure of metal foam composite sandwich structures with reasonable accuracy.
文摘Shell structure is widely used in industrial applications, such as in machinery, aerospace, ship and building fields, as well as containers of pressurized chemicals or liquefied natural gas. Graphite/epoxy composites has advantages of light weight, high strength, corrosion resistance, low expansion, low shrin kage and are often used in the form of composite pressure vessel for various engineering applications. In this study, the stress distributions of composite pressure vessel were analyzed. The finite element code ANSYS was used in analysis, in which the eight-node element SHELL 281 was adopted. The internal pressure 20 MPa, as in container of compressed natural gas, was applied inside the symmetrical cross-ply graphite/epoxy composite pressure vessel. The finite element model was established with suitable mesh size and boundary conditions. The stress distributions are discussed for the composite pressure vessel, especially for the inner two layers at the junction of semis pherical part. The Tsai-Hill criterion was used to assess the failure of composite pressure vessel.
