摘要
The out-of-plane fold is a common defect of composite materials during the manufacturing process and will greatly affect the compressive strength as well as the service life.Making it of great importance to investigate the influence of out-of-plane defects to the compressive strength of laminate plates of composite materials,and to understand the patterns of defect evolution.Therefore,the strip method is applied in this article to create out-of-plane defects with different aspect ratios in laminated plates of composite materials,and a compressive performance test is conducted to quantify the influence of out-of-plane defects.The result shows that the compressive strength becomes weaker with a greater aspect ratio.When the highest aspect ratio is set to 0.12 in the experiment,the compressive strength reduces by 36.1%.Then we establish a 3-D progressive damage model based on continuum mechanics,and write it into the UMAT subroutine together with the 3-D Hashin criteria and the non-linear degradation criteria of materials.3-D solid modeling is performed for the samples with an out-of-plane fold based on ABAQUS,and progressive damage analysis is conducted to acquire the inplane evolution process of initial failure strength with different laminates.The experimental results agree well with the simulation results.
