固体推进剂拉剪复合加载夹具设计及试验验证

In order to investigate the mechanical properties of solid propellant under tension-shear combined loading,the tension-shear combined loading fixture and specimen for solid propellant were designed based on the uniaxial tensile testing machine.This fixture improved based on the Arcan fixture adopts a modular design and is compatible with different tensile testing machines,which is suitable for loading at various loading angles.The tensile shear specimen can be directly clamped without opening holes according to the designed fixture and specimen,the uniaxial tensile,pure shear and tensile-shear tests were carried out,and the test results were compared with the finite element simulation results.The results show that there are clear differences in the ultimate loads of specimens under different loading conditions. The ultimate load of uniaxial tensile specimen is the largest,followed by the ultimate load of 45° tension-shear specimen,and the ultimate load of pure shear specimen is the smallest. The fracture initiation directions of specimens under different loading conditions are also different.The fracture initiation direction of the uniaxial tensile specimen is perpendicular to the axial direction of the specimen.The fracture initiation directions of pure shear specimen and tension-shear specimen are about 45° and 24.5° with the axial direction of specimen,respectively.The fixture designed in this paper can effectively complete the tension-shear test at different loading angles,and the experimental results agree well with the simulation results.