【正文】
成連續(xù)體而失去流動(dòng)性。在接融點(diǎn)范圍內(nèi)主要是凹形彎曲,當(dāng)兩個(gè)微粒相接觸時(shí),其凹度尤為明顯,以致此處的蒸汽特別低。4 結(jié) 論(1)通過沉降實(shí)驗(yàn)及Zeta電位和粘度值的測(cè)定,發(fā)現(xiàn)分散劑、pH值、固相體積分?jǐn)?shù)對(duì)SiC濃懸浮體的本征流變特性影響很大。參 考 文 獻(xiàn)1 , et al. Gelcasting a new ceramic forming process. Ceramic bulletin, 1991, 70(10): 1641~16492 Mark A. Janney, Ogbemi O. Omatete, Method for molding ceramics powders using a waterbased gelcasting process, US patent, , Sept. 8, 1992 3 楊金龍, 謝志鵬, 湯強(qiáng)等. αAl2O3懸浮體流變性及凝膠注模成型工藝研究. 硅酸鹽學(xué)報(bào), 1998, 26(1): 41~464 司文捷. 直接凝固注模成型Si3N4及SiC陶瓷-基本原理及工藝過程. 硅酸鹽學(xué)報(bào), 1996, 24(1): 32~375 Huang Y, Ma LG, Tang Q. Surface oxidation to improve waterbased gelcasting of silicon nitride. Journal Of Materials Science 2000, 35(14): 3519~35246 . Yang, . Xie, . Ma, et al. Study on Gelcasting Processing of High Power Rutile Capacitor. Key Engineering Materials, 1999, 161~163 7 Zhou, Longjie, Huang, Yong, Xie, Zhipeng. Gelcasting of concentrated aqueous silicon carbide suspension. Journal of the European Ceramic Society,2000, 20(1): 85~908 陳宗淇, 戴閩光. 膠體化學(xué) 北京:高等教育出版社 1984. 50~689 [英],吳大誠,古大治譯《流變學(xué)導(dǎo)引》 北京:中國石化出版社,1992,20~2910 柏平舟,,1991,4:58~59Study on Gelcasting and Property of Recrystallized Silicon CarbideYi ZhongZhou 1,2, Xie ZhiPeng1, Huang Yong1, Ma JingTao1(1 Department of Materials Science and Engineering, Tsinghua University, Beijing,100084;2 Department of Chemistry, Mengzi Teacher39。一般地,固相體積分?jǐn)?shù)越高,則坯體致密度越大,燒結(jié)體強(qiáng)度越高。 汽化凝結(jié)機(jī)理的動(dòng)力是表面曲率作用下蒸汽的型力差。則實(shí)驗(yàn)結(jié)果表明,60 Vol.%、65 Vol.%和70 Vol.%SiC懸浮體的固相體積分?jǐn)?shù)與粘度的流變曲線關(guān)系與高剪切極限時(shí)的Quemada模型較為相符。圖5給出了在最佳分散條件下,不同固相體積分?jǐn)?shù)的SiC懸浮體的粘度曲線。 分散劑對(duì)SiC懸浮體流變性的影響在凝膠注模成型工藝中,分散劑TMAH的加入