Tribology behaviors of energetic crystals play critical roles in the friction-induced hotspot in high-energy explosive, however, the binder and energetic crystals are not distinguished properly in previous investigations. In this study, for the first time, the nanoscale friction of β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (β-HMX) crystal is studied with nanoscratch tests under the ramping load mode. The results show that the nanoscale friction and wear of β-HMX crystal, as a typical energetic material, is highly depended on the applied load. The friction coefficient of β-HMX crystal is initially high when no discernible wear is observed, and then it decreases to a stable value which varies from ∼0.2 to ∼0.7, depending on the applied load, scratch direction, and crystal planes. The β-HMX (011) surfaces show weakly friction and wear anisotropy behavior; in contrast, the β-HMX (110) surfaces show strongly friction and wear anisotropy behavior where the friction coefficient, critical load for the elastic—plastic deformation transition and plastic—cracking deformation transition, and deformation index at higher normal load are highly depended on the scratch directions. Further analyses indicate the slip system and direction of β-HMX surfaces play key roles in determining the nanoscale friction and wear of β-HMX surfaces. The obtained results can provide deeper insight into the friction and wear of energetic crystal materials.

含能晶体的摩擦学行为在高能炸药摩擦引起的热点中起着至关重要的作用，然而，在以前的研究中，粘合剂和含能晶体并没有正确区分。本研究首次通过纳米划痕试验研究了β-八氢-1,3,5,7-四硝基-1,3,5,7-四佐辛（β-HMX）晶体在升温条件下的纳米级摩擦。加载模式。结果表明，β-HMX晶体作为一种典型的含能材料，其纳米级摩擦磨损高度依赖于所施加的载荷。当没有观察到明显的磨损时，β-HMX 晶体的摩擦系数最初很高，然后降低到稳定值，该值在~0.2 到~0.7 之间变化，具体取决于所施加的载荷、划痕方向和晶面。β-HMX(011)表面表现出微弱的摩擦磨损各向异性行为；相反，β-HMX（110）表面表现出强烈的摩擦和磨损各向异性行为，其中摩擦系数、弹塑性变形转变和塑性开裂变形转变的临界载荷以及较高法向载荷下的变形指数高度依赖于划痕方向。进一步的分析表明，β-HMX 表面的滑移系统和方向在确定 β-HMX 表面的纳米级摩擦和磨损方面起着关键作用。获得的结果可以更深入地了解含能晶体材料的摩擦和磨损。弹塑性变形转变和塑性裂纹变形转变的临界载荷以及较高法向载荷下的变形指数高度依赖于划痕方向。进一步的分析表明，β-HMX 表面的滑移系统和方向在确定 β-HMX 表面的纳米级摩擦和磨损方面起着关键作用。获得的结果可以更深入地了解含能晶体材料的摩擦和磨损。弹塑性变形转变和塑性裂纹变形转变的临界载荷以及较高法向载荷下的变形指数高度依赖于划痕方向。进一步的分析表明，β-HMX 表面的滑移系统和方向在确定 β-HMX 表面的纳米级摩擦和磨损方面起着关键作用。获得的结果可以更深入地了解含能晶体材料的摩擦和磨损。