Research On Impact Damage And Residual Strength Under High Temperature Of Composite Structure

The advanced composite materials are used more widely in aeronautic and astronautic structuresbecause of its excellent material mechanical properties. The laminated composites are inevitably to beimpacted by low energy and low velocity during manufacture and in service, and impacted loadingcan cause extensive sub-surface damage which can’t be observed on the laminate surface. And thesedamage weaken the strength of laminated composite structures seriously. The spacecraft’s componentsusually work in high temperature conditions, and the properties of laminated composites reduced inhigh temperature conditions. Therefore, it’s very important to research the impact properties andresidual strength in high temperature conditions after impact of laminated composite structures.Research works in this paper can be summarized as follows:1. The model of predicting the residual strength of laminated composites under hightemperature condition is established, which is based on the virtual work principle of incremental formand the theory of unidirectional ply. The impact damage statues of laminated composites are set to theinitial status of residual strength prediction, and combined with the progressive damage analysistheory, a whole-process analysis method for research of the impact process under room temperatureand the residual strength of laminated composites under high temperature condition after impact isproposed.2. Based on ANSYS software platform, a progressive damage analysis program which is usedto predict the residual strength of laminated composites under temperature condition after impact isdeveloped by using ANSYS parameter design language. This program can predict the damage failureprocess and the residual strength of laminated composites under high temperature conditions afterimpact.3. The impact tests of T300/BMP350laminated composites with two different measures arecarried out, the influence of measures to laminated composites is analyzed by experimental results.The residual strength of laminated composites under room temperature and300℃after impact istested, the effect of temperature and impact energy to the residual strength of laminated compositeafter impact is researched.4. The influence rule of temperature to the residual tensile and compressive strength is studiedby the whole-process analysis method which is developed in this paper. The experimental results andnumerical simulation results show that the residual strength of laminated composites under the same temperature after impact is reduced while impact energy rises, and the residual strength of laminatedcomposites under300℃is lower than the residual strength of laminated composites under roomtemperature after the same energy impact.