Hot-pressed 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)-based polymer bonded explosives (PBX) will show significant anisotropic and irreversible expansion properties, resulting in both the deterioration of their performance and weapon reliability issues. The anisotropic mechanical and irreversible expansion characteristics of TATB-based PBX have shown to be closely related to the crystal orientation. In this work, the orientations of TATB crystals in PBX under different thermal–mechanical coupling loading conditions were studied by neutron diffraction measurement technology. The microstructures were observed by computed tomography (CT) and scanning electron microscopy (SEM), and the effects of hot pressing parameters (temperature and pressure) on the TATB crystal orientation were systematically analyzed. Combining the density and compression strength of the formed samples, the optimal hot pressing parameters were determined. The results showed that during the in-situ compression process, the TATB crystals would be reoriented. The rotation angle of the (002) plane was mainly concentrated within a 35° angle from the perpendicular pressing direction. After hot compaction, the rotation angle moved from 35° to 52°, and the orientation of the TATB crystals had obvious rebound phenomenon. The (002) plane orientation degree was related to the deformation, fragmentation, and reorientation of the TATB crystals, as well as the phase transition, thermal softening, and gap filling of the binder, and the interfacial interactions. In order to obtain higher detonation energy, better mechanical properties and better shape stability of the formed samples, (120 °C, 140 MPa) was selected as the optimal hot pressing parameters for TATB-based PBX.

热压1,3,5-三氨基-2,4,6-三硝基苯（TATB）基聚合物粘结炸药（PBX）将表现出显着的各向异性和不可逆膨胀特性，导致其性能恶化和武器可靠性问题. 基于 TATB 的 PBX 的各向异性机械和不可逆膨胀特性已显示与晶体取向密切相关。在这项工作中，通过中子衍射测量技术研究了不同热机械耦合负载条件下 PBX 中 TATB 晶体的取向。通过计算机断层扫描（CT）和扫描电子显微镜（SEM）观察微观结构，系统分析了热压参数（温度和压力）对TATB晶体取向的影响。结合成型样品的密度和抗压强度，确定了最佳热压参数。结果表明，在原位压缩过程中，TATB晶体会发生重新取向。(002)面的旋转角度主要集中在与垂直压制方向成35°角内。热压后，旋转角度由35°变为52°，TATB晶体的取向出现明显的回弹现象。(002)面取向度与TATB晶体的变形、碎裂和重新取向以及粘结剂的相变、热软化和填隙以及界面相互作用有关。为了获得更高的爆轰能、更好的力学性能和成型样品更好的形状稳定性，（120 ℃，