Study On The Stress Of Carbon Fiber Reinforced Polymer Matrix Compositeby X Ray Diffraction

Because of its mechanical properties, the composite materials are gradually used in aviation industry for bearing capacity. In the process of the use of composite material, the stress tends to fail, and the replacement parts often affect the cost. Therefore, the real-time detection of the stress change of the composite material in service has important significance for the aviation industry.The residual stress of the composite was not directly obtained by the X ra y stress detector. In the composite material surface paste a layer of medium, through the detection of the residual stress of the medium and stress of the the medium after the load, acquire the load process of the medium stress change value. According t o the relationship of the stress value of the medium and the composite surface, the stress change value of the composite is calculated.The stainless steel wire and the aluminum foil were selected as the medium, respectively, and the residual stress was detected. The results show that the main stress of the stainless steel wire is-69.64±13.63 MPa at the distance of 0.5mm. The stability of the residual stress of the stainless steel wire was verified by two times. However, when the stainless steel wire bonding resin adhesive, the distribution of the residual stress of stainless steel wire is from-240.4MPa~249.3MPa. Large differences in the outcome of the reason is due to the thinness of stainless steel wire diameter, resin in the curing process of the mechanical properties of stainless steel wire effect dramatically, affecting stainless steel wire stability.By the use of X ray tester for aluminum foil for residual stress measurement, found in ensuring the aluminum foil surface roughness at the same time, to the appropriate annealing process can get aluminum foil stable residual stress values. Under the vacuum condition of 10-1Pa, aluminum foil was raised to 250℃ in 1.5 hours, and then the aluminum foil was cooled by annealing furnace for ten hours. The main stress of the aluminum foil is-7.57MPa~-42.93 MPa and the results are stable.The load of 300 N, 600 N, 900 N, 1200 N and 1500 N were applied to the composite materials at the bottom of the composite. Detection of aluminum foil and the resin matrix composite surface stress can be calculated. According to the numerical relationship between composite material and aluminum foil stress variation, calculated composite surface under different loading stress change value.ANSYS software is used on the composite pasting aluminum foil on the surface, loading process of numerical simulation, the aluminum foil section numerical simulation results and the 10 point of aluminium foil should force change values in the experiment are compared. When the load of the composite material is larger, the difference of the stress test results between the exper iment and simulation is smaller. There are many factors in the loading of composite materials, and there are abnormal points. In the process of loading, the change of the stress value of the composite is simulated, which helps to eliminate the abnormal points during the stress detection.