本文關(guān)鍵詞： 分散劑 漿料粘度 凝膠時(shí)間 單體用量 固相含量　出處：《西南科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：本論文主要采用注凝成型工藝制備莫來石顆粒增強(qiáng)磷酸鉻鋁復(fù)相陶瓷材料。選用丙烯酰胺為單體、N-N-亞甲基雙丙烯酰胺為交聯(lián)劑、N-N-N′-N′-四甲基乙二胺引發(fā)劑和過硫酸銨為催化劑,來探討各因素對(duì)成型工藝影響。通過沉降實(shí)驗(yàn)、Zeta電位和漿料粘度分析來研究陶瓷粉體在水中的分散機(jī)理。選用單因素實(shí)驗(yàn)分別來探討單體的用量、分散劑、p H值、固含量以及球磨時(shí)間等因素對(duì)成型所需的漿料流變性能的影響,以及單體、引發(fā)劑、催化劑用量和固化溫度對(duì)固化時(shí)間的影響。采用不同的有機(jī)分子對(duì)坯體表面起皮現(xiàn)象的抑制機(jī)理進(jìn)行探討,以及坯體的干燥工藝進(jìn)一步研究。主要研究了單體用量和固相含量對(duì)陶瓷素坯體和燒結(jié)體的機(jī)械性能、介電性能、微觀結(jié)構(gòu)的影響。在本試驗(yàn)條件下,在嘗試三種分散劑后,發(fā)現(xiàn)聚丙烯酸銨的分散效果最佳,在p H=10下,懸浮液的粘度較小,Zeta電位絕對(duì)值較大,綜合研究得漿料的分散屬于靜電位阻穩(wěn)定機(jī)制。對(duì)漿料的流變性能進(jìn)行研究分析,在一定的范圍內(nèi),漿料的粘度達(dá)到所需要的最高要求,分散劑的最佳用量為0.48wt%,單體濃度最佳值為14wt%,固相含量最高的53vol%,漿料的最佳球磨時(shí)間為8h,最佳p H值為9。通過對(duì)凝膠時(shí)間的控制分析得在單體用量為14wt%,催化劑用量為0.375ml/g,引發(fā)劑用量為0.625ml/g,凝膠固化溫度約為50℃時(shí),漿料的凝膠固化時(shí)間可控制在20~30min,有利于漿料注模的進(jìn)行。通過對(duì)注凝成型坯體的表面起皮現(xiàn)象和干燥變形問題研究,在聚丙烯酰胺、丙三醇和PVP三種高分子有機(jī)物的增潤下,加入丙三醇為2%時(shí)漿料粘度總體較低,凝膠固化時(shí)間適當(dāng),抑制坯體表面起皮現(xiàn)象較好。在室溫空氣、不同濃度的PEG溶液里干燥的濕坯體,在45%的PEG溶液里干燥的坯體失水率最大,且不易發(fā)生變形和開裂。通過對(duì)單體和固含量的分析研究,陶瓷坯體和燒結(jié)體的微觀形貌等各種性能會(huì)隨之發(fā)生較大變化。隨單體用量的增多,陶瓷坯體的彎曲強(qiáng)度、燒結(jié)線收縮率以及燒結(jié)體彎曲強(qiáng)度變化不大。但是固相含量對(duì)坯體以及燒結(jié)體的機(jī)械性能及介電性能等影響較大。在固相含量為53vol%時(shí),燒結(jié)體的彎曲強(qiáng)度可達(dá)181.30MPa,維氏硬度可達(dá)13.8GPa,密度為2.86g/cm3,平均介電常數(shù)為3.72,制備的陶瓷性能較好。從微觀結(jié)構(gòu)分析可得,材料內(nèi)部試樣的斷裂源主要來源于材料的內(nèi)部氣孔所致。
[Abstract]:In this paper, the mullite particle reinforced chromium aluminum phosphate multiphase ceramic material was prepared by the injection molding process. Acrylamide was used as the monomer N-N- methylene bisacrylamide as crosslinker, N-N-Na-tetramethyl ethylenediamine initiator and ammonium persulfate as catalyst. The dispersing mechanism of ceramic powder in water was studied by means of Zeta potential and viscosity analysis. The effect of solid content and ball milling time on rheological properties of slurry, monomer and initiator, The influence of the amount of catalyst and curing temperature on the curing time was discussed. The effects of monomer content and solid content on the mechanical properties, dielectric properties and microstructure of ceramic billets and sintered bodies were studied. It was found that the dispersion effect of ammonium polyacrylate was the best, and the viscosity of suspension solution was lower than that of Zeta potential at pH 10, the absolute value of Zeta potential was larger. It was found that the dispersion of the slurry belongs to the mechanism of electrostatic steric stability. The rheological properties of the slurry were studied and analyzed. Within a certain range, the viscosity of the slurry reaches the maximum required, The optimum dosage of dispersant is 0.48 wts, the optimum monomer concentration is 14wt, the highest solid content is 53volr, the optimum milling time of slurry is 8h, the optimal pH value is 9.Through the control of gel time, it is found that the monomer dosage is 14wtt and the catalyst dosage is 14wtmeter. When the amount of initiator is 0.625 ml / g, the gel curing temperature is about 50 鈩，

本文編號(hào)：1548099