功能材料
功能材料
공능재료
JOURNAL OF FUNCTIONAL MATERIALS
2014年
21期
21068-21071
,共4页
潘勃%李晓云%丘泰%杨建
潘勃%李曉雲%丘泰%楊建
반발%리효운%구태%양건
SiC%常压烧结氢气%显气孔率
SiC%常壓燒結氫氣%顯氣孔率
SiC%상압소결경기%현기공솔
SiC%pressureless sintering%hydrogen%apparent porosity
以质量分数30%Al2 O 3-70%SiC 为基,外加2%~10% CaO-TiO 2复合烧结助剂,制备了一系列SiC 基复相材料.研究了不同的烧成温度和 CaO-TiO 2含量对该复相材料烧结性能的影响.研究结果表明,1400~1500℃,随着烧结温度升高,烧结致密性明显提高.烧结温度为 1450℃时,试样基本致密.当烧结助剂达到10%(质量分数)时,显气孔率降至0.15%,陶瓷烧结致密.烧结助剂 CaO-TiO 2,α-Al2 O 3和方石英反应,在1200℃ 已经生成 CaAl2 Si2 O 8,在1300℃以后才开始生成 CaTiSiO 5,促进6 H-SiC 进一步氧化.烧结过程中,CaAl2 Si2 O 8转化为玻璃相,在促进莫来石生成的同时也使试样致密.在 1500℃,复合材料的主晶相为6 H-SiC 和莫来石.
以質量分數30%Al2 O 3-70%SiC 為基,外加2%~10% CaO-TiO 2複閤燒結助劑,製備瞭一繫列SiC 基複相材料.研究瞭不同的燒成溫度和 CaO-TiO 2含量對該複相材料燒結性能的影響.研究結果錶明,1400~1500℃,隨著燒結溫度升高,燒結緻密性明顯提高.燒結溫度為 1450℃時,試樣基本緻密.噹燒結助劑達到10%(質量分數)時,顯氣孔率降至0.15%,陶瓷燒結緻密.燒結助劑 CaO-TiO 2,α-Al2 O 3和方石英反應,在1200℃ 已經生成 CaAl2 Si2 O 8,在1300℃以後纔開始生成 CaTiSiO 5,促進6 H-SiC 進一步氧化.燒結過程中,CaAl2 Si2 O 8轉化為玻璃相,在促進莫來石生成的同時也使試樣緻密.在 1500℃,複閤材料的主晶相為6 H-SiC 和莫來石.
이질량분수30%Al2 O 3-70%SiC 위기,외가2%~10% CaO-TiO 2복합소결조제,제비료일계렬SiC 기복상재료.연구료불동적소성온도화 CaO-TiO 2함량대해복상재료소결성능적영향.연구결과표명,1400~1500℃,수착소결온도승고,소결치밀성명현제고.소결온도위 1450℃시,시양기본치밀.당소결조제체도10%(질량분수)시,현기공솔강지0.15%,도자소결치밀.소결조제 CaO-TiO 2,α-Al2 O 3화방석영반응,재1200℃ 이경생성 CaAl2 Si2 O 8,재1300℃이후재개시생성 CaTiSiO 5,촉진6 H-SiC 진일보양화.소결과정중,CaAl2 Si2 O 8전화위파리상,재촉진막래석생성적동시야사시양치밀.재 1500℃,복합재료적주정상위6 H-SiC 화막래석.
6 H-SiC and α-Al2 O 3 powders that as raw materials were mixed as mass ratio of 7 ∶3 with CaO and TiO 2 as sintering additives.The green body was preoxidated for 1 h at 1 200 ℃ after being pressed.Sic matrix composites were prepared by pressureless sintering for 1 h in hydrogen atmosphere.The effects of CaO-TiO 2 content and sintering temperature on the sintering properties and phasecomposition were investigated.The re-sults suggested that:withthe increase of sintering temperature form 1 400 to 1 500 ℃,the compactness im-proves significantly.At the sintering temperature of 1 450 ℃,the samples were basically compact.And the sam-ple's apparent porosity decreased to 0.15% with m (CaO-TiO 2 )of 10% added.The reaction of CaO-TiO 2 cristo-balite,with α-Al2 O 3 ,had generated CaAl2 Si2 O 8 at 1 200 ℃,and generated CaTiSiO 5 after 1 300 ℃,which pro-mote the 6 H-SiC further oxidation.In the process of sintering,CaAl2 Si2 O 8 formed liquid glass phase which de-posits mullite and promoted sample’s densification.At 1 500 ℃,the main crystal phase of the composite materi-al was 6 H-SiC,mullite.