Study On Milling Refinement And Safety Performance Of High Energy Explosive

The microcosmic configuration and particle size of explosives play an important role in their macroscopic performance.At present,mechanical ball milling is a safe,controllable,simple and effective method for refining energetic materials.Based on the research of domestic and foreign scholars,this thesis uses the original and simple refinement method to carry out experimental research.In this thesis,the mechanical ball milling method was used to refine the TKX-50 and the perovskite based on ammonium perchlorate from two aspects of different ball milling time and ball changing type.The micro nano and even nano explosives were prepared,and their thermal decomposition characteristics and mechanical sensitivity were analyzed and discussed.The main research contents are as follows:?1?TKX-50 micro nano explosive was prepared by setting the mechanical milling time of 6h,12h,24h and h,and only suitable for single size ball milling.The results of grain size refinement are weak after 6 hours of ball milling and 20-90?m after 12 hours of ball milling.However,when the milling time is doubled for 24 hours,the particles will be agglomerated and crystallized again in the process of filtration and drying after milling.The peak temperature of thermal decomposition of TKX-50 nanoparticles decreased by 5.1?after ball milling for 12hours,and the apparent activation energy and pre exponential factor of TKX-50 nanoparticles decreased a little,indicating that the samples have good thermal stability.The rebound phenomenon of samples with ball milling time of 24 hours is caused by the agglomeration of particles caused by long-time ball milling.Under the same conditions,the explosion probability of impact sensitivity is 28%,12%and 10%respectively,and the friction sensitivity is 48%,28%and 31%respectively.Compared with TKX-50?impact explosion probability of 25%,friction explosion probability of 64%?,there is a certain trend of decline.?2?The sensitized TKX-50 with nanostructure was successfully prepared by ball milling and heating drying.The product shows obvious layer by layer stacking phenomenon,and forms a network structure.The particle size range is 100³00nm,and it has good stability.The initial temperature of thermal decomposition of nano sensitized TKX-50 was 10.3?and2.2?lower than that of raw material.Its impact sensitivity(H₅₀:15.0cm,explosion probability100%)is higher than that of TKX-50(H₅₀:65cm,explosion probability 25%),and its friction sensitivity?100%?is 36%higher than that of TKX-50?64%?.Based on the mechanism of self-assembly process of agglomeration induced by heating and evaporation in liquid medium,the formation mechanism of micro nano layered structure is proposed.?3?The micro/nano samples were prepared by ball milling of ammonium perchlorate based perovskite with three particle sizes of mixed proportion.It has been proved to have good crystal stability by various characterization methods.Thermal analysis shows that the peak heat release temperature of micro nano DAP is 14.8?earlier than that of DAP raw materials,while the impact sensitivity?56%?and friction sensitivity?28%?of micro nano DAP are significantly improved compared with those of raw materials by using explosion probability method,and the friction sensitivity is also improved?from 78%to 63%?.