Cu-MOF/微米铝粉复合材料的制备与性能表征OA

To address the drawbacks of of micro-sized aluminum powder in traditional thermites,such as the low reaction rate,low energy release rate and high ignition temperature,a method of disrupting the aluminum surface passivation layer by liquid metal grain boundary penetration was adopted.On this basis,Cu-MOF with a high specific surface area was in-situ syn-thesized as a novel oxidant to prepare Cu-MOF/micro-aluminum powder composites with improved heat and mass transfer effi-ciency.The morphology and structure of the Cu-MOF/micro-aluminum powder composites were characterized by SEM,XRD,FTIR and XPS,and the thermal reaction performance of the composites was investigated by thermal analysis techniques.The re-sults showed that,cracks appear on the surface of liquid metal-modified aluminum(LM-Al),and the number and depth of cracks increased with the rise of liquid metal content.When the addition amount of liquid metal was 3％,the thermal reaction performance reached the optimum.Its exothermic onset temperature,exothermic peak temperature and exothermic termination temperature decreased to 883.9 ℃,936.1 ℃ and 985.2 ℃,respectively,and the oxidation weight gain up to 27.0％.Cu-MOF presented a regular octahedral morphology,and prolonging the synthesis time could effectively improve its loading capaci-ty on the Al surface and the thermal performance of the composites.Compared with Al@Cu-MOF1(11.15％and 10.83％)and LM-Al3@Cu-MOF1(2.71％and 15.28％)in terms of Cu-MOF loading capacity and oxidation weight gain,Al@Cu-MOF2(16.01％and 14.82％)and LM-Al3@Cu-MOF2(11.86％and 56.31％)are significantly improved.Both liquid metal modification and in-situ synthesis of Cu-MOF could improve the thermal reaction performance of Al,and the two treatments showed a synergistic effect.Among them,LM-Al3@Cu-MOF2 achieves the most remarkable performance improvement,its exothermic onset temperature was 50.05 ℃ lower than that of pure Al,and the oxidation weight gain at the high-temperature stage increased by 49.21％.