Abstract
The morphology of MAX phase powders significantly influences their microwave absorption properties.However,the traditional synthesis via solid-state reactions produces irregular powders,and the prepa-ration of MAX phase powders with specific morphology remains a challenge.Herein,(V0.8Ti0.1Cr0.1)2AlC MAX phase microrods were fabricated for the first time in NaCl/KCl molten salts using vanadium,tita-nium,chromium,aluminum,and short carbon fibers as precursors.It was found that despite acting as a carbon source,carbon fibers also acted as sacrificial templates.By adjusting the molar ratio of metal powders and short carbon fibers,a series of carbon fiber@(V0.8Ti0.1Cr0.1)2AIC microrods with core-sheath structure were also obtained.Carbon fiber@(V0.8Ti0.1Cr0.1)2AlC microrods with a molar ratio of 8:2 showed the optimum microwave absorption performance.The reflection loss(RL)value reached up to-63.26 dB at 2.40 mm,and the effective absorption bandwidth(EAB)was about 5.28 GHz with a thickness of 2.02 mm.Based on the electromagnetic parameter analysis and theoretical simulation,the enhanced mi-crowave absorption performance was attributed to the synergistic effect of different factors like dielectric loss,magnetic loss,multiple reflection,and scattering.This work offers a facile route to modulate the morphology of MAX phase powders and may accelerate its application as microwave absorbers.
基金项目
国家自然科学基金(51602184)
Natural Science Founda-tion of Shaanxi Province(2020JM-505)
Academic Talent Introduction Program of SUST(134080056)
NETL
NSTL
万方数据