To obtained the influence of high temperature and mechanical stress on the mechanical behaviors of polymer bonded explosive(PBX),the response of HMX-based PBX-1 and TATB-based PBX-2 under the action of different high temperature and mechanical stress were obtaitned based on the results of matrerial testing machine,and their change mechanism of mechanical properties are analyzed by dynamic mechanical analyzer (DMA) and scanning electron microscopy (SEM).Results show that the tensile strength and compressive strength of the two PBXs decrease with temperature increasing under coupled high temperature-mechanical stress loading at 25-90 ℃,but the failure strain undergos sahation at some temperature point,which is about 65 ℃ for PBX-1 and 35 ℃,about 55 ℃ and 75 ℃ for PBX-2.The response rule of PBX-1 subjected to sequence high temperature-mechanical stress loading contains two temperature ranges,25-150 ℃ for the first stage,the compressive strength and failure strain of materials under the action of the high temperature in the range almost do not change,150-200 ℃ for second stage,the failure strain increases with the increase of temperature,the compressive strength first decreases and then increases,which is lowest at 180 ℃.Under coupled high temperature-mechanical stress action,the phase change of binder and its change of viscoelastic characteristics is the main reason affecting the high temperature softening and deterioration of machanical properties of PBX.The deformation behaviors of PBX,especially its saltation of tensile failure strain and compressive failure strain are caused by softening-flow-viscous flow.At the same time,the failure mode of PBX changes from brittle fracture to debonding failure and the saltation temperature of PBX corresponds to the transition temperature of the state of matter for binder.For sequence high temperature-mechanical stress loading,the elastic recovery of binder and explosive crystal without damage is the main reason for no change of the mechanical properties of PBX-1 at 25-150 ℃.The crushing of explosive crystals occurs at high temperature around 180 ℃,leading to the compressive strength of PBX-1 reaches the minimum at around 180 ℃.%为了获得高温和机械应力对高聚物粘接炸药(PBX)力学行为的影响规律,基于材料试验机的结果获得了以HMX为基的PBX-1及以TATB为基的PBX-2在不同高温和机械应力作用下的力学响应规律,用动态热机械分析仪(DMA)和扫描电子显微镜(SEM)分析了它们的力学性能的变化机理.结果表明,在25～90 ℃高温-力耦合加载下,两种PBX的拉伸、压缩强度随温度升高而降低,但破坏应变在一些温度点产生突变,PBX-1的应变突变温度点约为65 ℃,PBX-2分别约为35、55 ℃和75 ℃;PBX-1的高温-力顺序加载响应规律包含两个温度段,25～150 ℃为第一阶段,该范围的高温作用下材料压缩强度和破坏应变几乎不会变化,150～200 ℃为第二阶段,破坏应变随温度升高而增大,压缩强度先减小后增大,在180 ℃最低.高温-力耦合作用下,粘结剂相态变化和粘弹特性改变是影响PBX高温软化和力学性能劣化的主要原因,其软化-流动-粘流化将引起PBX的变形行为特别是拉伸及压缩破坏应变的突变,同时导致PBX破坏模式由脆断向脱粘失效转变,PBX的突变温度与粘结剂的物态转变温度相对应.对于高温-力顺序加载,粘结剂弹性回复和炸药晶体无损伤是PBX-1在25～150 ℃力学性能不变的主要原因,炸药晶体在180 ℃附近会发生高温破碎,导致PBX-1的压缩强度在180 ℃附近达到最低值.
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