复杂受力环境下非均质炸药孔洞塌缩热点生成机理

Hot-spot Forming Mechanism of Holes Collapse in Heterogeneous Solid Explosives under Complicated Stress Environment

为探索非均质炸药在复杂冲击环境下的热点生成机理,在一维粘塑性孔洞塌缩热点模型中,考虑了外力为拉伸、压缩等不同作用模式,并引入了炸药力学性能随温度和损伤的影响,建立了炸药孔洞塌缩热点生成模型。模拟了孔洞在复杂冲击环境下的运动规律,对比分析了PBX9404炸药孔洞在持续压缩、拉伸与压缩交变两种不同外力作用下热点的产生模式。结果表明,持续压缩作用大于400 MPa下孔洞可产生热点,而拉伸与压缩交变作用250 MPa下孔洞可产生热点,因此,拉伸与压缩交变作用更容易产生热点。

To explore the hot-spot forming mechanism of heterogeneous solid explosives under the complicated impact environment, in the “hot-spot” model of one-dimensional viscoplastic holes collapse, different patterns of external forces, such as tension and compression were considered and the effects of temperature and damage on the mechanical performance of explosive were introduced. The “hot-spot” forming model of holes collapse for explosive was established. The movement regularity of holes under the complicated impact environment was simulated. The formation model of hot-spots of PBX9404 under two kinds of different external forces including continuous compression, and tension and compression alternate was compared and analyzed. Results show that under continuous compression action of greater than 400 MPa, the holes can produce hot spots, whereas under the alternating action of tension and compression of 250 MPa, the holes can produce hot spots. So the alternating action of tension and compression is easer to produce the hot spots.