The Research And Application Of ZrO₂ Hollow Heat-insulating Fibers Derived From Plant Template（Cebia Fiber）

Heat-insulting fibers,a kind of functional insulting material,possess high temperature resistence and low thermal conductivity,which mainly constituted by oxide ceramics.Among all oxide ceramics fibers,ZrO₂ fibers has the lowest thermal conductivity and hightest useage temperature and has extensively applied to the the areas of high temperature annealing furnace,crystal growth furnace,and chemical metallurgy,etc.The presently available ZrO₂fibers are solid structure and have the identical mechanism to heat-insulting.So,it is difficult to distinctly improve the heat insulting property of ZrO₂ solid fibers in this situation.It lack enough attentions to optimize the heat-insulting property of the ZrO₂ fibers from its structure.Compared with solid fibers,the hollow fibers are effective in suppressing the heat transfer,which belong to an advantaged structure to heat-insulting.Ceiba fibers own subtle hollow structure（20-35μm in diameter）,which give it innate advantage on thermal insulation.In this study,we apply“learn from nature”,take natural cebia fibers as a plant template,make ZrO₂materials inherite its hollow structure and fluffy morphology through the process of immersion,drying and sintering,etc.Thus,the ZrO₂ ceramics with inheriting the hollow structure of ceiba will obtain the structural advantage to heat-insulting.We also try to apply ZrO₂ hollow fibers as raw material to fabricate lightweight ZrO₂ fiberboards.The phase compositions,morphology,sintering process,pore size distribution,thermal conductivity and compressive strength of samples will be analysised by the tools of XRD,SEM,thermal weight loss analyzer,mercury porosimeter,plate thermal conductivity meter and universal test machine,respectively.The results show that ZrO₂fibers are hollow just as ceiba fibers,and its structure still maintain inner the lightweight ZrO₂ fiberboards.The thermal conductivity of ZrO₂hollow fibers are 25～48%lower than traditional ZrO₂solid fibers and the density and thermal conductivity of lightweight ZrO₂ fiberboard are 34～44%and 41～48%lower than the traditional samples,respectively.