發(fā)布時(shí)間：2018-11-16 18:54

【摘要】：本文采用溶膠-凝膠法以氧化釔為穩(wěn)定劑,通過(guò)乙酸與堿式碳酸鋯反應(yīng),制備出了乙酸聚鋯前驅(qū)體溶膠和氧化鋯前驅(qū)體凝膠纖維。通過(guò)研究加入H+/Zr4+的比例可知,當(dāng)加入的比例為1.8～1.9時(shí),可以得到穩(wěn)定性較好并具有可紡性的溶膠,通過(guò)粘度測(cè)試確定最佳的甩絲粘度為20～30Pa-S；采用FT-IR和TG-DTA測(cè)試分析,推斷出前驅(qū)體凝膠纖維中存在乙酸聚鋯的鏈?zhǔn)浇Y(jié)構(gòu),并以此為根據(jù)制定出了合理的熱處理制度。采用XRD、 SEM等測(cè)試手段對(duì)不同煅燒溫度得到的TZP陶瓷纖維和10wt%氧化鋁摻雜的AL2O3-3Y-TZP陶瓷纖維的纖維直徑、晶粒大小以及纖維強(qiáng)度進(jìn)行了研究,結(jié)果發(fā)現(xiàn)纖維直徑大約為10～12μm,晶粒大小大約為80～300nm,同時(shí)表明Al2O3的加入有抑制ZrO2晶粒長(zhǎng)大的作用,可增加其纖維的抗拉強(qiáng)度,并且最大抗拉強(qiáng)度可以達(dá)到1.2GPa。采用濕法成型制備氧化鋯基陶瓷纖維板,研究采用真空吸濾和加壓整平的工藝方法,將自制的Al2O3-3Y-TZP陶瓷連續(xù)纖維切成短纖維后加入成型劑,通過(guò)施加不同壓力制備出密度不同的纖維板濕坯,再經(jīng)烘干和1600℃高溫煅燒得到厚度均勻、表面平整的陶瓷纖維板。研究陶瓷纖維板1600℃下重?zé)臒峋�收縮,厚度方向永久線收縮較大,大約為10～12%,長(zhǎng)度方向和寬度方向較小,大約為2～4%；陶瓷纖維板的抗彎強(qiáng)度和抗壓強(qiáng)度隨密度升高而提高,當(dāng)密度達(dá)到0.55g/cm3時(shí),抗彎強(qiáng)度可以達(dá)到2.386MPa,抗壓強(qiáng)度可以達(dá)到0.353MPa。通過(guò)測(cè)試不同密度陶瓷纖維板1000℃下的導(dǎo)熱系數(shù),發(fā)現(xiàn)當(dāng)纖維板密度較低孔隙率較大時(shí),熱對(duì)流占主導(dǎo)地位,此時(shí)隨孔隙率增大,導(dǎo)熱系數(shù)增大；當(dāng)密度增大孔隙率降低時(shí),熱傳導(dǎo)占主導(dǎo)地位,此時(shí)隨密度增大,導(dǎo)熱系數(shù)增大；.最佳的密度范圍為0.4-0.8g/cm3。此時(shí)1000℃下的陶瓷纖維板導(dǎo)熱系數(shù)最低,大約為0.20～0.25W/m·K。通過(guò)添加不同比例的Al2O3-3Y-TZP陶瓷短纖維到氧化鋯泡沫陶瓷中,發(fā)現(xiàn)添加的纖維含量越高,其泡沫陶瓷的抗彎強(qiáng)度也越高；當(dāng)添加的短纖維含量為30wt%時(shí),抗彎強(qiáng)度為37.95MPa。
[Abstract]:In this paper, polyzirconium acetate precursor sol and zirconia precursor gel fiber were prepared by using yttrium oxide as stabilizer and acetic acid reacted with basic zirconium carbonate by sol-gel method. By studying the ratio of H / Zr4, the sol with good stability and spinnability can be obtained when the proportion of H / Zr4 is 1.8-1.9, and the optimum viscosity of the spun wire is 20 ~ 30Pa-S by viscosity test. The chain structure of polyzirconium acetate in the precursor gel fiber was inferred by means of FT-IR and TG-DTA, and a reasonable heat treatment system was worked out on the basis of it. The diameter, grain size and strength of TZP ceramic fibers and AL2O3-3Y-TZP ceramic fibers doped with 10 wt% alumina at different calcination temperatures were studied by means of XRD, SEM. The results show that the diameter of the fiber is about 10 ~ 12 渭 m and the grain size is about 80 ~ 300 nm. It is also shown that the addition of Al2O3 can inhibit the growth of ZrO2 grain and increase the tensile strength of the fiber, and the maximum tensile strength can reach 1.2 GPA. Zirconia based ceramic fiberboard was prepared by wet molding. Vacuum filtration and pressure leveling were used to cut the Al2O3-3Y-TZP ceramic continuous fiber into short fibers and then to add molding agent. The wetted board with different density and density was prepared by applying different pressure. Then the ceramic fiberboard with uniform thickness and flat surface was obtained by drying and calcining at 1600 鈩，

本文編號(hào)：2336351