Effect Of Coating Modification On The Performance Of Hydrogen Storage Materials And Their Mixed Explosives

Hydrogen storage materials have good application prospects in the field of energetic materials,with the characteristics of high activity,high energy,low environmental harm and so on.However,there are also some limitations:high activity,poor environmental adaptability,etc.The composite hydrogen storage materials X1 and X2 were selected as the research object in this thesis to explore the effects of before and after coating modification on the performances of the mixed explosives by analyzing their performances.The performances included combustion heat,moisture absorption,compatibility,mechanical sensitivity and explosive energy output characteristics of mixed explosives.The results of combustion heat study showed that the heat of combustion of the coated hydrogen storage material X2 was the highest,reaching 30.5633 MJ·kg^-1;the results of the moisture absorption test showed that X2 gained the least weight within 48 h in the air.The results suggested the coating modification process can effectively improve the environmental adaptability and long-term storage safety of hydrogen storage materials.In the minimum ignition energy experiment,the minimum ignition energy of the composite hydrogen storage material X1 ranged from 50 m J to 60 m J,which is only 1/2 of the minimum ignition energy of aluminum powder（100 m J～150 m J）.The minimum ignition energy of the coated composite hydrogen storage material X2 was greatly increased,between700 m J and 750 m J,indicating that the coated composite hydrogen storage material is more insensitive to external energy stimulation.The experimental results of flame propagation rate and dust explosion parameters all showed the law of Mg H₂>X1>X2>Al,indicating that the coating modification will not have much impact on the explosive performance of the composite hydrogen storage material.Compatibility test results showed that X1 had an average outgassing volume of 2.86 m L per gram of sample,which is unqualified for vacuum stability.And X2 had an outgassing volume of 0.79 m L per gram,which is qualified for vacuum stability.The outgassing volume of the mixture of X1 and RDX was as high as 11.48 m L per gram,and the two substances were incompatible;The outgassing volume of the mixture of X2 and RDX was 2.98 m L per gram,and the two substances were compatible.The results showed that coating modification can improve the stability of composite hydrogen storage materials.The results of friction sensitivity and impact sensitivity test show that compared with X1-based explosives,the friction sensitivity of X2-based explosives was reduced by 47.4%,the impact sensitivity was reduced by 42.9%,and X2-based explosives were more insensitive.The results showed that the coating modification of hydrogen storage materials can improve the safety of mixed explosives.The detonation heat test results of X1-based explosives and X2-based explosives were close.The underwater explosion results showed that the total energy released by the two explosives under each formula is close.The results show that the coating modification of the composite hydrogen storage material will not affect the energy output of the mixed explosive.