改性双基推进剂高应变率Ⅱ型断裂力学行为

Fracture mechanics behavior of modified double-base propellant in mode Ⅱ and high strain rate

使用紧密剪切试件,借助霍普金森压杆、万能材料实验机和高速摄影设备,研究了改性双基推进剂材料在高应变率条件下的断裂能、断裂韧性及裂纹传播路径。实验结果表明,改性双基推进剂材料在准静态条件下表现出明显的粘弹性,而在高应变率条件下表现出脆性。通过分析计算得到了紧密剪切试件在不同应变率下剪切面应力应变关系的变化规律、裂纹传播路径,以及1 000 s-1应变率下材料的断裂能、断裂韧性等力学参数。

Using compact shear specimen,the fracture energy, fracture toughness and crack propagation path of modified double-base propellant under a series of high strain rates were studied.Experiment was conducted with split Hopkinson pressure bar,universal material test machine and high-speed digital photographic equipments. The results show that modified double-base propellant materials exhibit obvious viscoelasticity under quasi-static conditions,but brittleness under high strain rates.At last,compact shear specimen’ s mechanical parameters like the rules of stress-strain relationship and crack propagation path under different strain rates, and the fracture energy,fracture toughness in 1 000 s-1 are obtained through analysis and calculation.