微流控制备HNS/F2604复合微球及其力学性能研究OA

To address the problems of irregular morphology and poor mechanical properties of conventional hexanitrostilbene(HNS)crystals,HNS/F2604 microspheres were fabricated via microfluidic technology.By combining Brazilian splitting tests with fi-nite element simulations,the mechanical properties and enhancement mechanism of the as-prepared microspheres were systemat-ically investigated.The results show that HNS/F2604 microspheres with good sphericity and smooth surfaces can be obtained when the dispersed phase flow rate is 0.05 mL·min-1,the continuous phase flow rate is 2.0 mL·min-1(flow rate ratio of 1∶40),and the collection temperature is 60℃.The microspheres retain the original crystalline structure of HNS,while their peak thermal decom-position temperature is 4.6℃lower than that of pure HNS.Brazilian splitting tests indicate that the pure HNS pellet has a peak load of 0.0065 kN and exhibits brittle fracture characteristics;in contrast,the peak load of the HNS/F2604 microsphere pellet increases to 0.072 kN,and its post-peak stress-displacement curve shows multi-stage attenuation,reflecting a transition to ductile fracture.The crack propagation morphology obtained from finite element simulations is in good agreement with the experimental fracture fea-tures.The HNS/F2604 composite microspheres prepared by microfluidic technology exhibit a remarkable toughening effect.