【摘要】：本文采用液相共沉淀法從粉體的制備-反應(yīng)機(jī)理研究-粉體表征-燒結(jié)-陶瓷表征這一流程系統(tǒng)的研究了氧化鋯增韌氧化鋁(ZTA)納米復(fù)合材料。首先探索了傳統(tǒng)反應(yīng)器和超重力反應(yīng)器中制備Al2O2-ZrO2納米復(fù)合粉體的工藝條件,用SEM、TEM、EDS、XRD以及粒度分布測(cè)試儀對(duì)粉體的形貌、顆粒大小、粒度分布、團(tuán)聚程度、元素分布均勻性等性能進(jìn)行了測(cè)試和。同時(shí),本文利用現(xiàn)有條件研究了Al2O3-ZrO2納米復(fù)合粉體的成型和燒結(jié)工藝條件,以自制粉體作為原料制備了ZTA納米復(fù)合陶瓷材料,并用SEM對(duì)陶瓷表面的形貌進(jìn)行了測(cè)試以及用阿基米德原理對(duì)陶瓷的密度和開(kāi)氣孔率進(jìn)行計(jì)算分析。根據(jù)對(duì)粉體以及陶瓷的各項(xiàng)測(cè)試,本文最終得到如下結(jié)果：(1)在傳統(tǒng)反應(yīng)器中當(dāng)以ZrOCl2、Y(NO3)3、AlNH4(SO4)2作為反應(yīng)物,以NH4HCO3作為沉淀劑,PEG 2000作為分散劑(用量為沉淀劑的2wt%),采用反共沉淀法作為制備方法,反應(yīng)溫度選取45℃并不斷以700r·min-1速率攪拌進(jìn)行攪拌,溶液的滴定速率設(shè)定為2mL·min-1并且在反應(yīng)過(guò)程中不滴加NH3H2O調(diào)節(jié)pH,而且經(jīng)過(guò)冷凍干燥后在900℃下進(jìn)行煅燒。在此條件下得到的粉體結(jié)晶度較高,Zr02以四方相存在；Al2O3-ZrO2納米粉體的形貌為球形,粉體顆粒粒徑較小,大約在50nm左右,粒度分布較窄,大約在30-70nm之間,而且粉體中Al元素和Zr分布均勻,沒(méi)有出現(xiàn)明顯的富集現(xiàn)象。(2)超重力旋轉(zhuǎn)床反應(yīng)器(RPB)的引入解決了傳統(tǒng)反應(yīng)器存在的組分分布不均勻以及團(tuán)聚問(wèn)題,提供了一種產(chǎn)物均勻性好,制備周期短,收率高,工藝過(guò)程簡(jiǎn)單的反應(yīng)器；同時(shí)該反應(yīng)器還克服了由于鋯離子和鋁離子沉淀所需pH相差過(guò)大所引起的組分沉淀不同步以及傳統(tǒng)反應(yīng)器反應(yīng)對(duì)滴定速率限制的弊端。本文系統(tǒng)的研究了超重力反應(yīng)器中進(jìn)料速率、轉(zhuǎn)速以及循環(huán)次數(shù)三個(gè)變量對(duì)于Al2O3-ZrO2納米復(fù)合粉體性能的影響,得出當(dāng)進(jìn)料速率在1000mL·min-1,旋轉(zhuǎn)填充床的轉(zhuǎn)速為1400r·min-1,循環(huán)次數(shù)為0次時(shí)得到的粉體性能最為優(yōu)異。對(duì)比傳統(tǒng)反應(yīng)器中的數(shù)據(jù)可以發(fā)現(xiàn),超重力旋轉(zhuǎn)床反應(yīng)器最終得到的粉體具有顆粒形貌更接近球形,顆粒粒徑更小(40nm),粒度分布更窄(30-50nm), Al元素和Zr元素分布更加均勻。除此之外,超重力反應(yīng)器在制備Al2O3-ZrO2納米復(fù)合粉體過(guò)程中進(jìn)料速率更快(500倍),反應(yīng)時(shí)間更短(1/500),能耗更低(1/70),因此,超重力反應(yīng)器的引入對(duì)于大規(guī)模制備Al2O3-ZrO2納米復(fù)合粉體具有重大意義。(3)探索了成型壓力、粘結(jié)劑、燒結(jié)溫度等工藝條件以及干燥方法、反應(yīng)器等影響粉體性能的條件對(duì)于陶瓷性能的影響,并最終得出結(jié)論成型壓力為200MPa時(shí)有利于陶瓷的燒結(jié),粘結(jié)劑的最佳添加濃度為1.5wt%,最佳燒結(jié)溫度為1600℃。而且性能優(yōu)異的粉體燒結(jié)性能也同樣優(yōu)異,尤其是超重力反應(yīng)器制備的粉體,在1500℃時(shí)即可達(dá)到較高的密度和較低的開(kāi)孔率。
[Abstract]:In this paper, zirconia toughened alumina (ZTA) nanocomposites were studied by liquid phase coprecipitation method from preparation of powders, study of reaction mechanism, characterization of powders, sintering and characterization of ceramics. Firstly, the preparation conditions of Al2O2-ZrO2 nano-composite powder in traditional reactor and hypergravity reactor were studied. The morphology, particle size, particle size distribution and agglomeration degree of the powder were measured by SEM,TEM,EDS,XRD and particle size distribution tester. The uniform distribution of elements and other properties were tested. At the same time, the forming and sintering conditions of Al2O3-ZrO2 nano-composite powder were studied by using the existing conditions. The ZTA nano-composite ceramic material was prepared by using self-made powder as raw material. The morphology of ceramic surface was measured by SEM and the density and porosity of ceramics were calculated and analyzed by Archimedes principle. According to the tests of powders and ceramics, the results are as follows: (1) ZrOCl2,Y (NO3) _ 3AlNH _ 4 (SO4) _ 2 is used as reactant and NH4HCO3 as precipitant in traditional reactor. PEG 2000 was used as dispersant (2 wt% of precipitator), anticoprecipitation method was used as preparation method, reaction temperature was 45 鈩，

本文編號(hào)：2415138