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1、昆明理-l大學(xué)頌:}:學(xué)位淪義摘要摘要本課題以Si粉為原料,以Ab03、Y203、A1203+Y203等為燒結(jié)助荊,以c粉、尿素和碳酸氨為造孔劑,采用反應(yīng)和常壓燒結(jié),同時(shí)結(jié)合造孔劑法制備氮化硅基多孔陶瓷。研究結(jié)果表明:采有上述復(fù)合工藝在1380℃下,可成功制備出氮化硅基多孔陶瓷材料;對(duì)A120j、Y203、觸203+Y203、A1、MgO、TiB2+MgO、Al(N03)3·9H20、Mg(N03)2·6H20作燒結(jié)助劑進(jìn)行研究,就物相組成和燒結(jié)性能而言,A1203和舢203+Y203較好,Y203次之;加入Al粉,雖可制得SiaN4,但衍射峰強(qiáng)度較低;對(duì)A
2、1203和A1203州r203系列作迸一步的分析,發(fā)現(xiàn)添加10%A1203和2%AH03+8%Y203作燒結(jié)助劑對(duì)氮化反應(yīng)有明顯的促進(jìn)作用。在工藝條件相同的情況下,以c粉+lO%A1203作添加劑,可生成B—Si3N4和a-Si3N4為主的Si3N4基多孔陶瓷,而且隨著C粉含量的增加,促進(jìn)了a-Si3N4—6-SiaN4的轉(zhuǎn)化;以C粉+(2%A1203+8%Y203)作添加劑,得到同樣的結(jié)果:以C粉+尿素做造孔劑,表明隨著尿素添加量的增加,雜相增加,說(shuō)明尿素對(duì)氮化反應(yīng)無(wú)明顯的促進(jìn)作用。本試驗(yàn)條件下所得到的Si3N4基多孔陶瓷,平均孔徑為30um,孔徑分布范圍
3、為7.95um-59,75um,氣孔率為16.2%-32.85%。SEM的測(cè)試結(jié)果表明試樣中以且.Si3N4和d.Si3N4為主,大量的棒狀組織交叉分布,同時(shí)夾雜有少量的等軸狀組織。此外,論文還對(duì)多孔陶瓷和氮化硅陶瓷的發(fā)展概況、制備方法及應(yīng)用進(jìn)行了綜述,同時(shí).介紹了國(guó)內(nèi)外多孔氮化硅陶瓷研究的最新進(jìn)展。關(guān)鍵詞:氮化硅;多孔陶瓷;反應(yīng)燒結(jié):造孔劑;常壓燒結(jié);燒結(jié)助劑;氮化硅基多孔陶瓷孔徑,氣孔率———堡塑堡三奎堂堡主堂焦堡塞壘!!!竺!AbstractThepaperdiscussedthatSilicon-nitridebasedporousceramicWa
4、Spreparedbyreaction’sinteringandpressless-sinteringwiththepowderofSi鵲rawmaterial.A1203andY203assinteringaids,carbonandcarbamide勰pore-formingagent.mresultsshowthat:At1380"C。Silicon-nitridebasedpomusceramicwasfabricatedsuccessfullybythecomplextechnology.Bystudyingseveralsinteringaids
5、,such硒A1203,Y203,A1203+Y203,MgO,TiB2+Mgo,MgOq03h·6H20andAlfN03b·9H20,A1203andA1203+Y203assintcringaidsa塢better,Y203takesthesecondplace.AlthoughSi3N4isobtainedwitllAI.theCPSofSi3N4isverylow.Fartherexperimentwasdonefor1hesystemofA1203andA1203+Y203.Bycomparison,10%Ah03or2%A1203+8%Y203
6、硒sinteringaidshasobviousfunctionforsynthesizingSi3N4.Inthesameconditionoftechnology,silicon-nitridebasedporousccr州c.whichiscomposedofB-Si3N4anda-Si3N4、糯obtained.C+10%A1203asadditives.Atthesanletime,theincreasingamountofcarbonisbepropmo惦toⅡ一to-Bphasetransformation.C+(2%A1203+8%Y203)
7、aSadditiveshavethesameconclusion.Themountofimpuritiesisincreasingastheincreasingamountofcarbamideforcarbonandcarbamide嬲pore-formingagent.Silicon—nitridebaSedporousceramicWasfabricated.Meanporesizeis30珊.rangingbetween7.95urnand59.75urn.Therangeofporosityis16.2%一32.85%.Microstructure
8、wasobservedbySEMandthecomp