CN111807811A - 多孔陶瓷及其制备方法 - Google Patents

多孔陶瓷及其制备方法 Download PDF

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CN111807811A
CN111807811A CN202010557083.XA CN202010557083A CN111807811A CN 111807811 A CN111807811 A CN 111807811A CN 202010557083 A CN202010557083 A CN 202010557083A CN 111807811 A CN111807811 A CN 111807811A
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chopped fibers
porous ceramic
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许小静
邱永斌
汪永清
李平
董国强
武振飞
张弘毅
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JIANGSU PROVINCE CERAMICS RESEARCH INSTITUTE CO LTD
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Abstract

本发明涉及一种陶瓷,尤其是多孔陶瓷,包括陶瓷短切纤维和陶瓷微珠,所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结形成多孔结构。本发明提供的多孔陶瓷由陶瓷短切纤维和陶瓷微珠形成三维构架,具有高孔隙率,成型速度快,制备工艺简单,成本低,性能稳定,较好的断裂韧性。

Description

多孔陶瓷及其制备方法
技术领域
本发明涉及一种陶瓷,尤其是多孔陶瓷及其制备方法。
背景技术
多孔陶瓷是一种拥有较多孔隙的无机非金属材料,通过利用材料中孔隙结构和表面积特点,与材料本身特质相结合,来达到所需要的力、热、磁、电等物理以及化学性能。多孔陶瓷不但具有陶瓷材料具有的耐热、耐高温、耐腐蚀等特点,而且,相较于致密材料,还具有小体积密度、大比表面积、轻重量等特点,同时还具有多孔材料的隔音、隔热、渗透性好等优点。由于多孔陶瓷兼具陶瓷与多孔材料的一些优点,因而具有广泛的使用前景,可以应用于化工、环保、冶金、能源、电子等领域。多孔陶瓷的孔隙成因主要是:直接成型制造孔隙和去除造孔物质形成孔隙。因此,根据不同的使用条件,也发展出针对使用其特点的制备工艺。其中应用比较成功,研究比较成熟的工艺有:挤出成型法、添加造孔剂法、生物模板法、有机泡沫浸渍法、冷冻干燥法、溶胶-凝胶法、发泡法等。
但是现有的多孔陶瓷的气孔率较低,并且材料具有各向异性,导致结构不稳定。
发明内容
为解决上述问题,本发明提供一种通过纤维和球体形成结构稳定、气孔率高的多孔陶瓷,具体技术方案为:
多孔陶瓷,包括陶瓷短切纤维和陶瓷微珠,所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结形成多孔结构。
通过采用上述技术方案,陶瓷微珠之间、陶瓷微珠与陶瓷短切纤维之间以及陶瓷短切纤维之间均能够形成气孔,因此能有效保证气孔率。
而陶瓷短切纤维实现连杆的作用,将陶瓷短切纤维和陶瓷微珠烧结在一起,形成稳固的结构。
进一步的,所述陶瓷短切纤维和所述陶瓷微珠形成层状具有同向性的网格层,所述多孔陶瓷由不少于两层的网格层叠加烧结而成,且所述网格层与网格层之间的所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结在一起。
通过采用上述技术方案,每一层均有同向性,有效保证了结构的稳定性。
多孔陶瓷,由以下材料按照质量份数制备而成:陶瓷短切纤维15~32份,陶瓷微珠1~3份,烧结助剂0~2份,光敏树脂40~80份,消泡剂0.05~0.1份,分散剂1~3份。
进一步的,所述陶瓷短切纤维为氧化铝纤维、莫来石纤维、氧化铈纤维、氧化锆纤维、硅酸铝纤维中的一种或多种。
进一步的,所述烧结助剂为氧化硅、氧化铝、氧化钇、氧化铈、氧化锆、氧化镁、氧化钙中的一种或多种;所述消泡剂为聚二甲基硅氧烷、脂肪醇、聚醚改性硅油中的一种或多种;所述分散剂为聚丙烯酸铵、聚乙二醇中的一种或两种。
多孔陶瓷的制备方法,由以下步骤制备而成:
制备陶瓷微珠;陶瓷短切纤维预处理:将陶瓷短切纤维进行分散、除渣和酸洗;光固化陶瓷浆料的制备:将预处理后陶瓷短切纤维、陶瓷微珠、光敏树脂、消泡剂、分散剂加入到搅拌机中搅拌,分散均匀后得到光固化陶瓷浆料;多孔陶瓷材料生坯的制备:将光固化陶瓷浆料均匀刷涂在平板上,然后用刮板向同一个方向刮1~3次形成多孔陶瓷层,刮完后用紫外光照射多孔陶瓷层,直到多孔陶瓷层固化;重复光固化陶瓷浆料刷涂的操作,使多孔陶瓷层达到所的层数或厚度;多孔陶瓷材料的烧结:取下制备好的多孔陶瓷材料生坯,并将多孔陶瓷材料生坯放置在窑炉中烧结,窑炉按照1~3℃/分钟的升温速度升高到1200~1500℃的最高烧成温度,并且在最高烧成温度保温1~3小时,然后随炉冷却,得到具有纤维交错排布的层状结构的多孔陶瓷材料。
进一步的,所述多孔陶瓷层的厚度在0.1~0.15mm,相邻的陶瓷层的纤维刷涂方向夹角为30~90°。
进一步的,所述陶瓷短切纤维的预处理包括以下步骤:在搅拌下,将陶瓷短切纤维加入含有分散剂的酸性水溶液中,其中,陶瓷短切纤维:水:分散剂为1:5~10:0.01~0.02;加完后继续搅拌5~10min,然后过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
进一步的,所述陶瓷微珠的制备方法包括以下步骤:取石英粉、长石粉、方解石粉、滑石粉、高岭土粉中不少于两种的粉体;将取好的粉体与烧结助剂、粘结剂、分散剂和水加入到球磨机中进行球磨粉碎和混合,其中,原料:球:水=1:1.5:0.6~0.8;球磨后通过250目筛选得到泥浆;将筛选后的泥浆进行喷雾造粒,得到粒径≤0.08mm的细粉;将细粉放置于窑炉中,按照0.5~1℃/分钟的升温速度将窑炉温度升高到最高1000~1100℃,并在最高温度恒温0.5~2小时,随炉冷却后得到陶瓷微珠。
进一步的,刷涂光固化陶瓷浆料前在平板上均匀刷涂一层热熔树脂;取下多孔陶瓷材料生坯时加热平板使热熔树脂融化。
与现有技术相比本发明具有以下有益效果:
本发明提供的多孔陶瓷由陶瓷短切纤维和陶瓷微珠形成三维构架,具有高孔隙率,成型速度快,制备工艺简单,成本低,性能稳定,较好的断裂韧性。
具体实施方式
现结合实施例对本发明作进一步说明。
实施例一
多孔陶瓷,包括陶瓷短切纤维和陶瓷微珠,所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结形成多孔结构。
陶瓷微珠之间、陶瓷微珠与陶瓷短切纤维之间以及陶瓷短切纤维之间均能够形成气孔,因此能有效保证气孔率。
而陶瓷短切纤维实现连杆的作用,将陶瓷短切纤维和陶瓷微珠烧结在一起,形成稳固的结构。
陶瓷微珠的直径不大于0.08mm。
多孔陶瓷的气孔率为40~80%。
实施例二
在上述实施例一的基础上,所述陶瓷短切纤维和所述陶瓷微珠形成层状具有同向性的网格层,所述多孔陶瓷由不少于两层的网格层叠加烧结而成,且所述网格层与网格层之间的所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结在一起。
每一层均有同向性,有效保证了结构的稳定性。
层装置结构通过刷涂形成,并且在刷涂时每层沿同一个方向刷涂,从而保证每层的陶瓷短切纤维和陶瓷微珠能够具有同向性。
网格层之间具有夹角,夹角的角度为30~90°,网格层具有夹角能形成交错结构,较粗结构能够有效保证网格层之间的陶瓷短切纤维与陶瓷微珠烧结在一起,从而保证网格层之间不会形成明显的分层现象,保证整体结构的稳定。
本发明在通过将陶瓷短切纤维、陶瓷微珠、光敏树脂、粘结剂等混合成浆料,进行人工搭建网格状孔道,通过紫外光照射光敏树脂实现快速固化,然后通过排胶烧成制得的多孔陶瓷材料孔隙率高,韧性大,过滤阻力小,过滤性能好,操作简单,成本低。
实施例三
在上述实施例一或实施例二的基础上,多孔陶瓷,由以下材料按照质量份数制备而成:陶瓷短切纤维15~32份,陶瓷微珠1~3份,烧结助剂0~2份,光敏树脂40~80份,消泡剂0.05~0.1份,分散剂1~3份。
所述陶瓷短切纤维为氧化铝纤维、莫来石纤维、氧化铈纤维、氧化锆纤维、硅酸铝纤维中的一种或多种。
所述烧结助剂为氧化硅、氧化铝、氧化钇、氧化铈、氧化锆、氧化镁、氧化钙中的一种或多种;所述消泡剂为聚二甲基硅氧烷、脂肪醇、聚醚改性硅油中的一种或多种;所述分散剂为聚丙烯酸铵、聚乙二醇中的一种或两种。
实施例四
多孔陶瓷的制备方法,由以下步骤制备而成:
制备陶瓷微珠;
陶瓷短切纤维预处理:将陶瓷短切纤维进行分散、除渣和酸洗;
光固化陶瓷浆料的制备:将预处理后陶瓷短切纤维、陶瓷微珠、光敏树脂、消泡剂、分散剂加入到搅拌机中搅拌,分散均匀后得到光固化陶瓷浆料;
多孔陶瓷材料生坯的制备:将光固化陶瓷浆料均匀刷涂在平板上,然后用刮板向同一个方向刮1~3次形成多孔陶瓷层,刮完后用紫外光照射多孔陶瓷层,直到多孔陶瓷层固化;重复光固化陶瓷浆料刷涂的操作,使多孔陶瓷层达到所的层数或厚度;
多孔陶瓷材料的烧结:取下制备好的多孔陶瓷材料生坯,并将多孔陶瓷材料生坯放置在窑炉中烧结,窑炉按照1~3℃/分钟的升温速度升高到1200~1500℃的最高烧成温度,并且在最高烧成温度保温1~3小时,然后随炉冷却,得到具有纤维交错排布的层状结构的多孔陶瓷材料。
紫外光照射时间一般为20~60秒,直到固定完成即可。
所述多孔陶瓷层的厚度在0.1~0.15mm,相邻的陶瓷层的纤维刷涂方向夹角为30~90°。
所述陶瓷短切纤维的预处理包括以下步骤:在搅拌下,将陶瓷短切纤维加入含有分散剂的酸性水溶液中,其中,陶瓷短切纤维:水:分散剂为1:5~10:0.01~0.02;加完后继续搅拌5~10min,然后过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
陶瓷短切纤维预处理所使用的酸性水溶液中所用酸为盐酸、硝酸、柠檬酸、氢氟酸,硫酸中的一种或多种。分散剂为聚丙烯酸铵。
所述陶瓷微珠的制备方法包括以下步骤:取石英粉、长石粉、方解石粉、滑石粉、高岭土粉中不少于两种的粉体;将取好的粉体与烧结助剂、粘结剂、分散剂和水加入到球磨机中进行球磨粉碎和混合,其中,原料:球:水=1:1.5:0.6~0.8;球磨后通过250目筛选得到泥浆;将筛选后的泥浆进行喷雾造粒,得到粒径≤0.08mm的细粉;将细粉放置于窑炉中,按照0.5~1℃/分钟的升温速度将窑炉温度升高到最高1000~1100℃,并在最高温度恒温0.5~2小时,随炉冷却后得到陶瓷微珠。
陶瓷微珠为化学组成含有硅、铝、钙、镁、钾、钠的粉体经喷雾造粒制成。
刷涂光固化陶瓷浆料前在平板上均匀刷涂一层热熔树脂;取下多孔陶瓷材料生坯时加热平板使热熔树脂融化。
平板为陶瓷平板。
至少一个实施例中:
陶瓷微珠的制备:按质量份数,将25份高岭土、8份钾长石、10份滑石、1份氧化镁、2份氧化钙,8份硅溶胶,5份PVA,1份聚丙烯酸铵,水36.8份,加入球瓶中,进行球磨粉碎和混合,原料:球:水=1:1.5:0.8,球磨24小时后获得250目筛余≤0.1%的泥浆,用所获泥浆喷雾造粒并过筛得到粒径≤0.08mm的细粉,将细粉放置于窑炉中,按照0.5℃/分钟的升温速度将窑炉温度升高到最高1000℃,并在最高温度恒温0.5小时,随炉冷却后得到陶瓷微珠。
陶瓷短切纤维的预处理:在搅拌状态下,将陶瓷短切纤维加入含有聚丙烯酸铵的酸性水溶液中,陶瓷短切纤维:水:聚丙烯酸铵质量比为1:5:0.01;加完后继续搅拌5min,过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
光固化陶瓷浆料的制备:将15份陶瓷短切纤维、1陶瓷微珠、3份氧化钙,80份光敏树脂、0.05份聚二甲基硅氧烷、1份聚丙烯酸铵,在搅拌速度为300转/分钟下加到容器中,分散均匀,制得混合浆料。
多孔陶瓷材料生坯的制备:在陶瓷基材上均匀刷涂一层热熔树脂冷却固化;在固化层上将光固化陶瓷浆料沿着一个方向均匀刷涂在多孔陶瓷基材上,顺着刷涂方向用刮板刮2次形成多孔陶瓷层,刮完后用紫外光均匀照射多孔陶瓷层20s固化;多孔陶瓷层固化后刷涂下一层,每一层的多孔陶瓷层厚度为50微米,相邻多孔陶瓷层的纤维刷涂方向夹角为30°;重复刷涂固化到需要的厚度。加热陶瓷平板使热熔树脂融化,然后取下制备的多孔陶瓷材料生坯。
多孔陶瓷材料的烧结:将多孔陶瓷材料生坯放置在高温炉中烧结成一种具有纤维交错排布的层状结构多孔陶瓷,以纤维与纤维,纤维与陶瓷微珠,陶瓷微珠与陶瓷微珠中的一种或多种方式连接形成三维构架,最高烧成温度为1300℃。
至少一个实施例中:
陶瓷微珠的制备:按质量份数,将20份高岭土、8份钾长石、5份方解石、8份滑石、2份氧化镁、1份氧化钙,8份硅溶胶,5份PVA,1份聚丙烯酸铵,水30.8份,加入球瓶中,进行球磨粉碎和混合,原料:球:水=1:1.5:0.7,球磨18小时后获得250目筛余≤0.1%的泥浆,用所获泥浆喷雾造粒并过筛得到粒径≤0.08mm的细粉,将细粉放置于窑炉中,按照0.8℃/分钟的升温速度将窑炉温度升高到最高1050℃,并在最高温度恒温1小时,随炉冷却后得到陶瓷微珠。
陶瓷短切纤维的预处理:在搅拌下,将氧化铝陶瓷短切纤维加入含有聚丙烯酸铵的氢氟酸水溶液中,陶瓷短切纤维:水:聚丙烯酸铵质量比为1:8:0.02。加完后继续搅拌8min,过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
光固化陶瓷浆料的制备:将22份硅酸铝陶瓷短切纤维、2份陶瓷微珠、4份氧化镁、71份光敏树脂、0.06份聚二甲基硅氧烷、1份聚丙烯酸铵,在搅拌速度为500转/分钟下加到容器中,分散均匀,制得混合浆料。
多孔陶瓷材料生坯的制备:在陶瓷基材上均匀刷涂一层热熔树脂冷却固化。在固化层上将混合浆料沿着一个方向均匀刷涂在多孔陶瓷基材上,顺着刷涂方向用刮板刮3次形成多孔陶瓷层,刮完后用紫外光均匀照射多孔陶瓷层25s固化。一层多孔陶瓷层固化后刷涂下一层多孔陶瓷层,每一层多孔陶瓷层的厚度为60微米,相邻的多孔陶瓷层的纤维刷涂方向夹角为50°,重复刷涂固化到需要的厚度。加热陶瓷平板使热熔树脂融化,然后取下制备的多孔陶瓷材料生坯。
多孔陶瓷材料的烧结:将多孔陶瓷材料生坯放置在高温炉中烧结成一种具有纤维交错排布的层状结构多孔多孔陶瓷材料,以纤维与纤维,纤维与陶瓷微珠,陶瓷微珠与陶瓷微珠中的一种或多种方式连接形成三维构架,最高烧成温度为1350℃。
至少一个实施例中:
陶瓷微珠的制备:按质量份数,将20份高岭土、8份钾长石、5份石英、6份滑石、2份氧化钙、1份氧化钙,8份硅溶胶,5份PVA,1份聚丙烯酸铵,水25.2份,加入球瓶中,进行球磨粉碎和混合,原料:球:水=1:1.5:0.6,球磨15小时后获得250目筛余≤0.1%的泥浆,用所获泥浆喷雾造粒并过筛得到粒径≤0.08mm的细粉,将细粉放置于窑炉中,按照1℃/分钟的升温速度将窑炉温度升高到最高1100℃,并在最高温度恒温2小时,随炉冷却后得到陶瓷微珠。
陶瓷短切纤维的预处理:在搅拌下,将氧化铝陶瓷短切纤维加入含有聚丙烯酸铵的酸性水溶液中,陶瓷短切纤维:水:聚丙烯酸铵质量比为1:10:0.02。加完后继续搅拌10min,过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
光固化陶瓷浆料的制备:将32份莫来石短切纤维、3份陶瓷微珠、4份氧化镁、60份光敏树脂、0.06份聚二甲基硅氧烷、1份聚丙烯酸铵,在搅拌速度为500转/分钟下加到容器中,分散均匀,制得混合浆料。
多孔陶瓷材料生坯的制备:在陶瓷基材上均匀刷涂一层热熔树脂冷却固化。在固化层上将混合浆料沿着一个方向均匀刷涂在多孔陶瓷基材上,顺着刷涂方向用刮板刮3次形成多孔陶瓷层,刮完后用紫外光均匀照射多孔陶瓷层30s固化。一层多孔陶瓷层固化后刷涂下一层多孔陶瓷层,每一层多孔陶瓷层的厚度为100微米,相邻的多孔陶瓷层纤维刷涂方向夹角为70°。重复刷涂固化到需要的厚度。加热陶瓷平板使热熔树脂融化,然后取下制备的多孔陶瓷材料生坯。
多孔陶瓷材料的烧结:将多孔陶瓷材料放置在高温炉中烧结成一种具有纤维交错排布的层状结构多孔多孔陶瓷材料,以纤维与纤维,纤维与陶瓷微珠,陶瓷微珠与陶瓷微珠中的一种或多种方式连接形成三维构架,最高烧成温度为1400℃。
利用光照(特定波长)条件引发有机单体(常为液态)或预聚物发生链式反应,形成固体聚合物的过程称为光固化反应。陶瓷光固化体系浆料作为液态树脂与陶瓷粉末的混合体。其流变特性可认为,在相同材料体系下,随着陶瓷浆料固相含量(陶瓷粉末加入量)的增加,陶瓷光固化体系浆料的粘度呈急速上升趋势。在实际实现光固化成型的过程中,过高的浆料粘度往往会导致陶瓷粉末发生团聚现象以及难以实现浆料的铺平,过高的浆料粘度将大大降低流动性,然而,为保证后续陶瓷坯体的烧结性能,一个足够高的固相含量又是必不可少的。因此对于陶瓷光固化成型体系来说,低粘度与高的固相体积粉体是一对相矛盾的命题。本发明有效解决了该问题,通过采用陶瓷短切纤维和陶瓷微珠实现陶瓷材料的相互接触,保持了烧结性能,并通过每层多孔陶瓷层沿同一方向刷多次,使同向性交换,并且能保证陶瓷短切纤维之间、陶瓷微珠之间、陶瓷短切纤维与陶瓷微珠之间形成连接,进而保证气孔率。
本方法还解决了现有方法中工艺复杂,成本较高的问题。
本方法采用喷雾造粒法制得粒径小于0.08mm的陶瓷微珠,以陶瓷短切纤维、陶瓷微珠、光敏树脂为原料,通过刮板定向刮涂浆料,控制每一层纤维的方向,层与层间纤维夹角为30~90°,每一层用紫外光照射实现快速固化。本发明制备的多孔陶瓷材料气孔率为40%~80%,以纤维与纤维,纤维与陶瓷微珠,陶瓷微珠与陶瓷微珠中的一种或多种方式连接形成三维构架,具有成本低,操作简单,性能优异的特点。
以上结合具体实施例描述了本发明的技术原理。这些描述只是为了解释本发明的原理,而不能以任何方式解释为对本发明保护范围的限制。基于此处的解释,本领域的技术人员不需要付出创造性的劳动即可联想到本发明的其它具体实施方式,这些方式都将落入本发明权利要求的保护范围之内。

Claims (10)

1.多孔陶瓷,其特征在于,包括陶瓷短切纤维和陶瓷微珠,所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结形成多孔结构。
2.根据权利要求1所述的多孔陶瓷,其特征在于,
所述陶瓷短切纤维和所述陶瓷微珠形成层状具有同向性的网格层,所述多孔陶瓷由不少于两层的网格层叠加烧结而成,且所述网格层与网格层之间的所述陶瓷短切纤维与所述陶瓷微珠、所述陶瓷短切纤维与所述陶瓷短切纤维、所述陶瓷微珠与所述陶瓷微珠均相互烧结在一起。
3.多孔陶瓷,其特征在于,由以下材料按照质量份数制备而成:
陶瓷短切纤维15~32份,陶瓷微珠1~3份,烧结助剂0~2份,光敏树脂40~80份,消泡剂0.05~0.1份,分散剂1~3份。
4.根据权利要求3所述的多孔陶瓷,其特征在于,
所述陶瓷短切纤维为氧化铝纤维、莫来石纤维、氧化铈纤维、氧化锆纤维、硅酸铝纤维中的一种或多种。
5.根据权利要求3所述的多孔陶瓷,其特征在于,
所述烧结助剂为氧化硅、氧化铝、氧化钇、氧化铈、氧化锆、氧化镁、氧化钙中的一种或多种;
所述消泡剂为聚二甲基硅氧烷、脂肪醇、聚醚改性硅油中的一种或多种;
所述分散剂为聚丙烯酸铵、聚乙二醇中的一种或两种。
6.多孔陶瓷的制备方法,其特征在于,由以下步骤制备而成:
制备陶瓷微珠;
陶瓷短切纤维预处理:将陶瓷短切纤维进行分散、除渣和酸洗;
光固化陶瓷浆料的制备:将预处理后陶瓷短切纤维、陶瓷微珠、光敏树脂、消泡剂、分散剂加入到搅拌机中搅拌,分散均匀后得到光固化陶瓷浆料;
多孔陶瓷材料生坯的制备:将光固化陶瓷浆料均匀刷涂在平板上,然后用刮板向同一个方向刮1~3次形成多孔陶瓷层,刮完后用紫外光照射多孔陶瓷层,直到多孔陶瓷层固化;重复光固化陶瓷浆料刷涂的操作,使多孔陶瓷层达到所的层数或厚度;
多孔陶瓷材料的烧结:取下制备好的多孔陶瓷材料生坯,并将多孔陶瓷材料生坯放置在窑炉中烧结,窑炉按照1~3℃/分钟的升温速度升高到1200~1500℃的最高烧成温度,并且在最高烧成温度保温1~3小时,然后随炉冷却,得到具有纤维交错排布的层状结构的多孔陶瓷材料。
7.根据权利要求6所述的多孔陶瓷的制备方法,其特征在于,
所述多孔陶瓷层的厚度在0.1~0.15mm,相邻的陶瓷层的纤维刷涂方向夹角为30~90°。
8.根据权利要求6所述的多孔陶瓷的制备方法,其特征在于,
所述陶瓷短切纤维的预处理包括以下步骤:
在搅拌下,将陶瓷短切纤维加入含有分散剂的酸性水溶液中,其中,陶瓷短切纤维:水:分散剂为1:5~10:0.01~0.02;
加完后继续搅拌5~10min,然后过筛网水洗至pH为7,滤干多余水分,放入烘箱100℃烘干备用。
9.根据权利要求6所述的多孔陶瓷的制备方法,其特征在于,
所述陶瓷微珠的制备方法包括以下步骤:
取石英粉、长石粉、方解石粉、滑石粉、高岭土粉中不少于两种的粉体;
将取好的粉体与烧结助剂、粘结剂、分散剂和水加入到球磨机中进行球磨粉碎和混合,其中,原料:球:水=1:1.5:0.6~0.8;
球磨后通过250目筛选得到泥浆;
将筛选后的泥浆进行喷雾造粒,得到粒径≤0.08mm的细粉;
将细粉放置于窑炉中,按照0.5~1℃/分钟的升温速度将窑炉温度升高到最高1000~1100℃,并在最高温度恒温0.5~2小时,随炉冷却后得到陶瓷微珠。
10.根据权利要求6所述的多孔陶瓷的制备方法,其特征在于,
刷涂光固化陶瓷浆料前在平板上均匀刷涂一层热熔树脂;
取下多孔陶瓷材料生坯时加热平板使热熔树脂融化。
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