Study Of Heat-insulated Hollow Ceramic Fibers Derive From Plant Templates(Pampas Grass Fibers)

Ceramic fiber materials have the advantages of light weight,high temperature resistance,good thermal stability,low thermal conductivity,and low specific heat.They are widely used in aviation,aerospace,metallurgy,and thermal insulation materials area.Common thermal insulation ceramic fibers are mainly zirconia fibers and alumina fibers.However,ceramic fibers which fabricated by traditional method are solid.The heat insulation resistance of traditional fibers is not as good as hollow fibers due to their poor porosity and large aperture.There are many plant fibers with hollow structure in nature,such as reed,pampas grass and imperata spend fibers.Their hollow structure lock the air in a long and thin fiber tube,hinders the heat convection,and improves the heat insulation performance.This enlightens us that we have prepared ceramic fiber with similar structure by using the plant fiber with micron level hollow structure as the template.Compared with the traditional solid fiber,the thermal insulation performance is significantly improved.In this study,natural hollow plant fiber pampas as a template is adopted.The natural template fibers were immersed in precursor solution and later desiccated in vacuum drying chamber to obtain precursor fibers.Then the precursor fibers were finally placed in a muffle furnace and sintered at high temperature.We finally achieve YSZ fibers,Al₂O₃-ZrO₂(Ce O₂)fibers and aluminum borate fibers,which are heat insulation and stable with similar structure as template fibers.The solution system and sintering temperature of YSZ fibers derived from pampas grass are investigated.We explored the differences in thermal insulation properties of two common aluminum borate fibers prepared using pampas grass as a template.The differences in phase composition and thermal insulation properties of pampas grass relic Al₂O₃-ZrO₂(Ce O₂)fibers prepared with different Al₂O₃ and ZrO₂ ratios were explored.SEM,XRD,EDS,FITR,mercury porosimetry and thermal conductivity measuring apparatus are used to characterize ceramic fibers.The result confirms that ceramic fibers inherit the hollow structure from templates and this structure endows fibers excellent thermal resistance.