熱解炭的微觀(guān)結構及其測試方法

2007年第4期CARBON TECHNIQUES200T№4第26卷炭套技術(shù)Vol 26·綜合述評·熱解炭的微觀(guān)結構及其測試方法劉立海,黃啟忠,謝志勇,王秀飛(中南大學(xué)粉末冶金國家重點(diǎn)實(shí)驗室,湖南長(cháng)沙410083)摘要:主要介紹了利用正交偏光顯微鏡(PLM)、X射線(xiàn)射(XRD)透射電鏡(TEM)和喇曼光譜(RS)等測試方法對采用化學(xué)氣相沉積(cD)法制備的c/C復合材料的熱解炭的表面微觀(guān)形貌沉積炭層間距dm微晶尺寸L及其石墨化度等參數進(jìn)行表征和測量從而判斷沉積的熱解炭的織構類(lèi)型(光滑層粗糙層和各向同性炭),并且分析了上述各種測試手段的優(yōu)缺點(diǎn)關(guān)健詞:化學(xué)氣相沉積;C/C復合材料;熱解炭;織構中圖分類(lèi)號:TQ127.1·1文獻標識碼:A文章編號:1001-3741(2007)04001706MICROSTRUCTURAL CHARACTERIZATIONAND MEASUREMENTS OF PYROLYTICCARBONLIU Li-hai, HUANG Qi-zhong, XIE Zhi-yong, WANG Xiu-feiState Key Laboratory for Powder Metallurgy, Central South University, Changsha410083. ChinaAbstract: In this paper, in order to judge the structure (SL, RL, ISO)of pyrolytic carbons prepared by chemicaldeposition(CVD), the methods for observation and measurement of the surface morphologies and structural paprameterssuch as the interlayer spacing don, crystallite size L and graphitization degree of pyrolytic carbons were introducedwhich includes the polarized light microscopy(PLM), scanning electron microscopy(SEM), tansmission electron mirecopy(TEM), X-ray diffraction (XRD) and Raman spectroscopy. The advantages and disadvantages of each measurement were also analysized.Key words Chemical vapor deposition; carbon/ carbon composites; pyrolytic carbonitexture對于C/C復合材料而言,結構與性能之間的關(guān)料;而各向同性結構具有較好的各向同性、生物相系至關(guān)重要,化學(xué)氣相沉積制備的C/C復合材料一容性、密封性,可用于生物材料、密封材料等。熱解般由各向同性的炭纖維和各向異性的熱解炭組炭是氣態(tài)碳氫化合物在熱基體表面通過(guò)脫氫環(huán)化成。材料的性能主要取決于基體,即沉積的熱解炭作用沉積而形成的炭材料。文獻[1~6]研究表明不類(lèi)型。例如,光滑層結構具有很好的高溫力學(xué)性能,同類(lèi)型的熱解炭對C/C復合材料的摩擦磨損、力學(xué)主要用于高溫結構件、抗燒蝕件等;粗糙層結構具性能等影響較大。因此,對熱解炭組織結構的類(lèi)型有較好的摩擦磨損性能,適用于高性能飛機剎車(chē)材進(jìn)行表征和測量是十分重要的。對熱解炭織構類(lèi)型作者簡(jiǎn)介:劉立海男1981年出生,碩士研究生,E-mil:hiulihaigodc@163.com。收稿日期:2007-02-02炭素技術(shù)07年進(jìn)行表征和測量的方法有多種。例如,采用偏光顯起偏器起偏器微鏡( Polarized Light Microscopy,PLM)、X射線(xiàn)衍射檢偏器(X- Ray diffraction)、透射電鏡( Transmission Elec了消光角ron Microscopy,TFM)、喇曼光譜( Raman Spectrum等方法。H前,國內外對熱鮮炭織構類(lèi)型的判別主要基于」述各種方法,但是對上述各種方法綜述性的報道尚未見(jiàn)報。本文主要對上述方法作簡(jiǎn)要的綜旋轉述性報道,并提出各自方法的優(yōu)缺點(diǎn)。減偏器1熱解炭類(lèi)型和結構特征E1.1偏光顯微鏡圖2偏光顯微鏡測量消光角示意圖Fig 2 Schematic diagram ot extinction angle measure under熱解炭材料最初是采用PLM進(jìn)行研究的PLMPierson和 Lieberman0等為首的美國 Sadia實(shí)驗室,對沉積在纖維氈的熱解炭進(jìn)行了深入細致的 Rough laminar,RL)和各向問(wèn)性熱解炭( isotroPic研究。他們將在偏光下觀(guān)察到的熱解炭的微觀(guān)結構IS0),以及以上三種中任意兩者或者兩者以上交替劃分為三類(lèi):光滑層( Smooth laminar,SL)粗糙層組合而形成的帶狀結構( Banded Structure,Bs),如圖1所示1從圖1可以看出,其中SL在光學(xué)上各向異性,柑位移較低,無(wú)生長(cháng)錐形成,呈現清晰可見(jiàn)的十字消光線(xiàn)且視覺(jué)效果光滑、呈灰色、裂紋顯著(zhù);RL光學(xué)活性較高,具有生長(cháng)錐特征,呈現大量不規則的十字消光線(xiàn)且視覺(jué)效果粗糙、呈銀灰色、無(wú)裂紋;ISO光學(xué)各向同性,相位移為零,觀(guān)察不到十字消光線(xiàn)。隨后, Diefendorf和1 okarsky I3基于沉積的炭層關(guān)于基面的擇優(yōu)取向程度不同而其在PIM下的旋(a)sL光性不同定義了消光角Aea在PLM屮,當兩個(gè)棱鏡正交時(shí),視場(chǎng)中出現黑十字線(xiàn),通過(guò)逆時(shí)針旋轉檢偏器,第一象限逐漸消失然后又變亮,在即將變亮的那一瞬間,分析器刻度盤(pán)上顯示的即為消光角數值,如圖2所示1各種熱解炭的微觀(guān)結構可以用Ae來(lái)表征,Ae的大小與織構的擇優(yōu)取向程度有關(guān),擇優(yōu)取向程度越高,Ae越大,反之亦然:ISO(Ae<4),DL(4°≤A<12°),SL(12°≤Aec≥50亂的堆積狀態(tài)。aa=180°da=A/(2ein0);g=(0.3340-da)/(0.3440-0.3354);L=(K)/(Bo08)0.340nm≤d≤0.344mmda≈0.343nm≥70%20%≤g<70%23.9mm≤L9.5rm≤L≤16.5nm7mm≤L≤llmmR-= IG/lp2007年2005,5:1201~1207.結論[13] DIEFENDORF R J, TOKARSKY E w. Air Force Report,1971,AF33(615)-70-C-1530偏光顯微鏡是利用材料的各向異性對光的反14]廖寄喬,黃伯云,黃志鋒,等.熱解炭微觀(guān)結構的表征射強度不同進(jìn)行測量的;TEM是在X射線(xiàn)衍射基礎熱解炭各向異性的偏振光分析[門(mén).理化檢驗一物理分冊.2002,38():501-506上結合選區電子衍射(SAED)對熱解炭的織構進(jìn)行(1 LAVINAC, LANGLAIS F. FERON O.aa.Mhem測量分析;X射線(xiàn)衍射是通過(guò)計算微晶的尺寸、層間ture of the pyrocarbon matrix in carbon/carbon composites距和石墨化度等參數對熱解炭的織構進(jìn)行判定;而[I. Comp Sci Technol, 2001, 65:339-345喇曼光譜是通過(guò)圖譜測量D峰和G峰的峰強比來(lái)[16] TRESSAUD A, CHAMBON M, GUPTA V, et a fluo-判定熱解炭的織構類(lèi)型。但是各種手段都有自己的rine-intercalnted carbon fibers Il A transmission electron優(yōu)點(diǎn)和缺點(diǎn),使用單一手段難以對材料結構進(jìn)行全croecopy[J]. Carbon, 1995, 33(9): 1339-1345面分析,采用多種手段,相互補充,才能更加有效分17BoKR0 SJC Deposition, structure and properties of py-析熱解炭的結構。rolytic carbon[J]. Chemistry and Physics, 1969, 5: 1-118[18] LEBERMAN M L PIERSON H 0. Effect of gas phase參考文:conditions on resultant matrix pyrocarbons in carbon/car[1] XIANG XIONG, BAI-YUN HUANG, JLANG-HONGbon composites[J]. Carbon, 1974, 12(3):233-241[19] PIERSON H O, LIEBERMAN M L The chemical vaporLI, et al. Friction behaviors of carbon/carbon compositeswitb diberent pyrolytic carbon texures [J]. Carbon, 2006deposition of carbon on carbon fibers[J].Carbon, 197513(3):159-166.2】肖春,朱光明,侯衛權,等,熱解炭合量對C/C復合[20] GOMA J, OBERLIN A. Characterization of low tempera-材料性能的影響[.火箭推進(jìn),2005,31(6):45-49ture pyrocarbons obtained bystrates[. Carbon,1986,24(2):135-142[3]BENZAINGR W, HUTTINGER K J. Chemistry and21]李江鴻,張紅波,熊舞,等.不同纖維體積分數cⅥchanical and structural properties of infiltrated carbon fber炭/炭復合材料的石墨化度打復合材料學(xué)報,2005,22felt J]. Carbon,199,37:1311-1322.4】 REZNIK B, GERTHSEN D, W ZHANG,etal.Teue{22】李圣華,石蠱電極生產(chǎn)[M】北京:冶金工業(yè)出版社,1997hanges in the matrix of an infiltrated carbon fiber feltstudied by polarized light microscopy and selected are[23] MIGUEL A, MONTES M, ROBERT J, et al.Ramaelectron difraction[J. Carbon, 2003, 41: 376-380spectroscopy study of M carbon fibers: eBfect of Plasma5]陳脾飛,龔偉平,張紅波,等.高溫熱處理對光滑層熱treatment on the interfacial properties of single fiber/epoxy解炭裂紋形成的影響[].粉末冶金材料科學(xué)與工程2006,11(4):210~213.[24] IZER E, GANTNER E, ROZPLOCH E, et al. Applica【61于澍,黃啟忠,黃伯云,等.炭/炭復合材料化學(xué)氣相tion of Laser-Raman spectroscopy for characterization of沉積工藝進(jìn)展[J].粉未冶金材料科學(xué)與工程,2006,carbon fiber[J]. High temperalures-High pressures1974,9(5):537~54.11(5):262-2671AA則1n202,“(2 ALLEROT JM,0 E OURRAT X, MOUCHON A, et E[7] REZNIK B, HUTTINGER K J. Oa theQuantitative structural and textural assessment of laminarFU-QIN ZHANG, BAI-YUN HUANG, QI-ZHONGPyrocarbons through Raman spectroscopy, eleetronHUANG, et al. Effects of the inter-face on the graphiti-diffraction and few other technique [J], Carbon, 2006.zation of a carbon fiber/pyrolytic carbon composite[J][26] TUINSTRA F, KOENIGJL Raman spectrum of graphite([J]The Journal of chemical physics, 1970, 53(3): 1126-11309】 PIERSON H O, LIEBERMAN M L The chemical vapor(2]張福勤,黃伯云黃啟忠,等.C/C復合材料石漫化度deposition of earbon on carbon fber[J].Carbon, 1975的啊曼光譜表征[J],無(wú)機材料學(xué)報,2003,18(213:159-225.[10) OBERLIN A Pyrocarbons[].Carbon,2002,40:7-24[11] LIEBERMAN M L PIERSON H O. Eect of gas phase[28]傳秀云,李賀軍,盧錦花,化學(xué)氣相滲透磺/碳復合材料熱解碳光性特征一熱解碳十字消光機理探討.西conditions on resultant matrix pyrocarbons in carban/car-bon composites[J]. Carbon, 1974, 12: 233-241北工業(yè)大學(xué)學(xué)報,20,23(5):657-661.2]謝志勇,黃啟忠,蘇哲安,等.耦合物理場(chǎng)CW制備I29〕 GRANNFF E. Kinetics of graphitization of carbon-fl炭/炭復合材料及其機理研究[J].無(wú)機材料學(xué)報,carbon-matrix composites Carbon, 1974: 12: 405-416