Bending properties and failure mechanism of fiber rare earth magnesium alloy super hybrid laminates

Abstract

The fiber metal laminate is mainly used in the fuselage wall board, wing skin and other key parts of the aircraft. The structural parts mentioned above bear a large bending moment during the service, which requires that the fiber metal laminate should have the ability to resist bending deformation. In this study, fiber rare earth magnesium alloy super hybrid laminate, a new type of fuselage structure material was used as the research object. Three-point bending was used to test the bending strength of unidirectional and cross-ply rare earth magnesium alloy super hybrid laminates under different span-to-thickness ratios (L/h). SEM was used to observe the bending failure morphology of the laminate, and the progressive damage behavior of the laminate during the bending process was analyzed with finite element simulation. The research results show that the different L/h values have a certain effect on the bending strength of rare earth magnesium alloy super hybrid laminates. The effective bending failure L/h values of unidirectional and orthogonal rare earth magnesium alloy super hybrid laminates are 16-22 and 16-20 respectively. Through SEM observation and finite element analysis, it is concluded that the bending failure modes of laminate include elastic stage, plastic stage, fiber and epoxy resin matrix fracture stage, rare earth magnesium alloy fracture stage and laminate delamination stage.

Keywords

• rare earth magnesium alloy
• fmls
• bending properties
• failure mechanism
• finite element analysis