采用环境扫描电镜(ESEM)技术对AP颗粒在低温（150～240℃）段进行快速和慢速升温试验，研究了整个形貌的变化历程。结果表明，ESEM能够直观地发现AP颗粒在低温下存在气相反应；在150～170℃，AP颗粒表面开始出现微孔；在170～190℃，微孔数量急剧增加；在190～210℃，表面形成多孔结构；在210℃～240℃，表面出现坍塌及体积皱缩。上述过程不受升温速率的快慢而显著改变，不同升温速率对AP颗粒的影响可能是快速升温容易导致整个颗粒受热不均并在较高的环境温度开始反应，最终在颗粒表面形成裂纹，但它不改变AP的整个反应历程。通过对AP的低温反应历程分析认为：170℃是AP颗粒气相反应的起始点；低温反应的极限失重率达到30%；环境压力可能是影响AP低温分解反应的主要因素。

The sub-micronε-CL-20 with average particle sizeof 721.9nm was prepared by gas anti-solvent(GAS) technique. Some of thetechnical conditions affecting the particle size and modes of crystallizationof CL-20 were studied. Small scale gap test and impact sensitivity of sub-micronCL-20 and its raw material were tested. Optimized parameters of preparing thesub-micronε-CL-20 are obtained: average pressure increasevelocity 4.0MPa/min, solution concentration 8.0g/100mL, system temperature 50℃ andsystem pressure 10.5MPa.It can be foundthat its gap thickness is decreased 58.6% and its characteristic droop heightis higher 84.1% than that of its raw materials.