Preparation Of Magnesium Based Hydrogen Storage Catalytic Materials And Its Applied Research In The Propellant

Magnesium based hydrogen storage catalyzed material Mg₂NiH₄ and Mg₂CuH₃ were prepared with Replacement-Diffusion Method, MgH₂ with Direct-Hydrogenation Method, and their structure was determined by XRD,SEM,TEM,ICP,DSC,TG. The results show that Mg₂NiH₄ is singleness crystal and octahedron. The capacity of hydrogen is 3.588%, the hydrogen release temperature is 292.4℃. Mg₂CuH₃ is a mixture of MgCu₂ and MgH₂. The optimal conditions to prepare magnesium based hydrogen storage catalyzed material were also studied. The catalytic effects of these magnesium based hydrogen storage catalyzed material on the thermal decomposition of AP and AP/HTPB composite solid propellant were studied by thermal analysis(DSC-TG). 5wt% Mg-2NiH₄,Mg₂CuH₃ and MgH₂ decreased the second thermal decomposition temperature of AP by 84.4℃,110.4℃and 86.2℃. the DSC heat release of AP in the presence of Mg₂NiH₄,Mg₂CuH₃ and MgH₂ was obviously higher than that of pure AP. This reveals that magnesium based hydrogen storage catalyzed material have good catalytic effects on the second thermal decomposition of AE MgH₂ can also catalyze the first decomposition of AP, while Mg₂NiH₄ and Mg₂CuH₃ hinder it. The catalytic effect of Mg₂NiH₄,Mg₂CuH₃ and MgH₂ was enhanced with the increase of the proportional of their. Mg₂NiH₄,Mg₂CuH₃ and MgH₂ also decreased the thermal decomposition temperature of the AP/HTPB propellant, and its heat release in creased clearly, showing catalytic effects on the thermal decomposition of the AP/HTPB propellant. LiH also have catalytic effects to the thermal decomposition of AP and AP/HTPB composite solid propellant. The mechanism of catalyzing the thermal decomposition of AP is that hydrogen in material,metal and oxiders acts in the process of the decomposition of AR.At the same time, nanometer FeCu alloy was prepared by chemical reduction. The catalytic effects of nanometer FeCu alloy on the thermal decomposition of AP and AP/HTPB composite solid propellant were studied by thermal analysis(DSC-TG). The catalytic effects is good. Quantitative change is not too influence to the catalytic effects. The proportion of Fe and Cu is important; The catalytic effects of Fe0.5Cu0.5 is best.