本文選題：LTCC厚膜　切入點(diǎn)：受約束燒結(jié)　出處：《合肥工業(yè)大學(xué)》2015年博士論文　論文類型：學(xué)位論文

【摘要】：由于受約束燒結(jié)問題的普遍性和實(shí)用性,對(duì)燒結(jié)體受約束燒結(jié)致密化行為的研究具有重大的應(yīng)用價(jià)值和科學(xué)意義。近年來,LTCC厚膜材料逐漸成為電子元器件和集成電路領(lǐng)域內(nèi)應(yīng)用最為廣泛的材料,但是對(duì)LTCC厚膜材料的受約束燒結(jié)致密化行為缺乏系統(tǒng)的理論研究。連續(xù)介質(zhì)力學(xué)燒結(jié)理論能夠?qū)崿F(xiàn)對(duì)受約束燒結(jié)致密化行為的預(yù)測(cè)和模擬,得到了越來越多的關(guān)注。本文以LTCC厚膜材料為研究對(duì)象,通過原位光學(xué)膨脹儀觀測(cè)系統(tǒng),研究了多種約束條件下LTCC厚膜的燒結(jié)致密化行為�；谶B續(xù)介質(zhì)力學(xué)燒結(jié)理論,成功地使用垂直燒結(jié)方法測(cè)定了LTCC厚膜材料各向同性及各向異性的燒結(jié)參數(shù),并根據(jù)測(cè)定的燒結(jié)參數(shù)對(duì)基板約束LTCC厚膜的燒結(jié)致密化行為進(jìn)行了分析和預(yù)測(cè)。研究了多種約束燒結(jié)條件下LTCC厚膜內(nèi)部顯微結(jié)構(gòu)的演變規(guī)律。本文的主要結(jié)論如下：(1)通過對(duì)流延工藝的探索和嘗試,成功使用銀峰(YF)低介微波陶瓷粉體和浩普(HP)鐵氧體粉體制備出了厚度可控、一致性好、致密的LTCC厚膜材料。并可通過工藝參數(shù)的調(diào)控,制備出不同厚度的厚膜。搭建了原位光學(xué)膨脹儀,并結(jié)合垂直燒結(jié)樣品臺(tái)及石英搖擺臂測(cè)定了多種形式的受約束LTCC厚膜材料的燒結(jié)致密化行為。(2)采用薄膜懸掛垂直燒結(jié)方法,分別測(cè)定了幾種LTCC厚膜材料,DuPont 951 tape(DU),Ferro A6M tape(FE)和YF厚膜的單軸粘度。通過研究發(fā)現(xiàn),受到自身重力影響,垂直燒結(jié)的LTCC厚膜在垂直方向上的燒結(jié)致密化行為會(huì)受到細(xì)微的影響,但是其內(nèi)部微結(jié)構(gòu)仍然能保持各向同性。LTCC厚膜的單軸粘度隨相對(duì)密度的增加呈現(xiàn)出非線性增長(zhǎng),在低密度范圍內(nèi)增長(zhǎng)緩慢,在較高密度范圍內(nèi)則增長(zhǎng)迅速。通過對(duì)比研究發(fā)現(xiàn),實(shí)驗(yàn)測(cè)定的厚膜的單軸粘度與Raj模型預(yù)測(cè)的結(jié)果具有很好的一致性。通過In (Ep)與1/T之間的Arrhenius方程,求解出了DU厚膜的單軸粘度激活能,其數(shù)值290±47kJ/mol。(3)為測(cè)定LTCC厚膜材料的各向異性燒結(jié)參數(shù),設(shè)計(jì)了單軸加載燒結(jié)實(shí)驗(yàn),對(duì)垂直燒結(jié)的FE厚膜施加單軸載荷,并通過調(diào)節(jié)單軸載荷的大小,實(shí)現(xiàn)了FE厚膜在單軸方向上的零收縮燒結(jié)。研究發(fā)現(xiàn)單軸載荷可以明顯改變加載方向上厚膜材料的燒結(jié)致密化行為,但是對(duì)厚膜整體的燒結(jié)致密化過程影響不大。通過對(duì)單軸加載FE厚膜顯微結(jié)構(gòu)的研究發(fā)現(xiàn),厚膜內(nèi)的氣孔在燒結(jié)過程中會(huì)逐漸沿著單軸加載方向取向,而且氣孔的取向程度隨著單軸載荷的增大而逐漸增加。根據(jù)厚膜單軸零收縮燒結(jié)所對(duì)應(yīng)的邊界條件簡(jiǎn)化了各向異性連續(xù)介質(zhì)力學(xué)方程,成功得到適用于計(jì)算厚膜各向異性的燒結(jié)參數(shù)的公式,并計(jì)算出在單軸零收縮條件下FE厚膜的單軸粘度和粘性泊松比系數(shù)。通過與各向同性燒結(jié)參數(shù)的對(duì)比發(fā)現(xiàn),單軸零收縮燒結(jié)LTCC厚膜的單軸粘度明顯增大,同時(shí)粘性泊松比系數(shù)隨密度增加而逐漸下降。(4)研究了硬質(zhì)基板約束FE厚膜的燒結(jié)致密化行為。由于基板的約束力,在燒結(jié)過程中FE厚膜在基板平面方向上的燒結(jié)致密化過程被抑制,只能在厚度方向上產(chǎn)生燒結(jié)收縮,在燒結(jié)后樣品的密度低于自由燒結(jié)厚膜。在燒結(jié)過程中厚膜內(nèi)出現(xiàn)了明顯的各向異性微結(jié)構(gòu),隨著密度的增加氣孔會(huì)逐漸沿著平行于基板的方向取向。通過阿倫尼烏斯公式(Arrhenius)和主燒結(jié)曲線(MSC)兩種方法研究了硬質(zhì)基板約束的FE厚膜的燒結(jié)激活能。使用阿倫尼烏斯方法求得自由燒結(jié)厚膜的燒結(jié)激活能為530±30kJ/mol,而基板約束厚膜的燒結(jié)激活隨著密度而逐漸降低,由640 kJ/mol逐漸下降至359kJ/mol。而使用主燒結(jié)曲線方法求得的自由燒結(jié)厚膜燒結(jié)激活能為510 kJ/mol,基板約束厚膜燒結(jié)激活能為440kJ/mol。通過對(duì)比發(fā)現(xiàn),硬質(zhì)基板約束厚膜的燒結(jié)激活能明顯低于自由燒結(jié)厚膜。我們分別使用各向同性及各向異性連續(xù)介質(zhì)力學(xué)本構(gòu)方程對(duì)硬質(zhì)基板約束厚膜的燒結(jié)致密化行為進(jìn)行預(yù)測(cè)和模擬。通過對(duì)比實(shí)驗(yàn)測(cè)定和理論預(yù)測(cè)的結(jié)果發(fā)現(xiàn),各向異性連續(xù)介質(zhì)力學(xué)方程能更準(zhǔn)確地預(yù)測(cè)出受約束厚膜在較高的密度范圍內(nèi)(75%)的燒結(jié)致密化行為。(5)通過對(duì)柔性基板約束HP厚膜研究發(fā)現(xiàn),在燒結(jié)過程中厚膜會(huì)產(chǎn)生向上的翹曲變形。與硬質(zhì)基板約束的厚膜相比,柔性基板通過翹曲釋放了一部分基板約束力,厚膜的燒結(jié)致密化過程受到的抑制作用減弱,燒結(jié)后厚膜的密度更高。使用各向同性連續(xù)介質(zhì)力學(xué)方程預(yù)測(cè)了受約束厚膜的致密化速率,與實(shí)驗(yàn)測(cè)定的結(jié)果對(duì)比后發(fā)現(xiàn)兩者在低密度區(qū)能保持較好的一致性,但是隨著密度的增加,兩者之間的差異逐漸增大。通過分析了柔性基板約束HP厚膜的顯微結(jié)構(gòu)發(fā)現(xiàn),厚膜內(nèi)的氣孔存在明顯的梯度分布,氣孔率在遠(yuǎn)離基板的位置逐漸降低。通過柔性基板的翹曲變形求解出了作用于厚膜上的基板約束力,并與各向同性連續(xù)介質(zhì)力學(xué)預(yù)測(cè)的結(jié)果對(duì)比后發(fā)現(xiàn),各向同性模型預(yù)測(cè)出的基板應(yīng)力明顯低于實(shí)際測(cè)定的應(yīng)力。
[Abstract]:Because of the universality and practicability of constrained sintering problem, has great application value and scientific significance to study on the sintered constrained sintering densification behavior. In recent years, LTCC material has gradually become electronic components and integrated circuits in the field of the most widely used materials, but the lack of systematic theoretical research of constrained sintering behavior the densification of LTCC thick film material. To achieve the forecast and Simulation of constrained sintering densification behavior of sintered continuum mechanics theory, has attracted more and more attention. This paper research on the LTCC thick film material, by in situ optical dilatometer observation system, studied the Sintering Densification behavior of LTCC thick film multi constraints under the sintering theory. Based on continuum mechanics, the successful use of the vertical sintering method of sintering parameters of LTCC thick film material isotropy and anisotropy were determined, and According to the Sintering Densification behavior of sintering parameters on the determination of substrate bound LTCC thick film was analyzed and predicted. On the evolution of LTCC thick film microstructures of various constraints sintering conditions. The main conclusions of this paper are as follows: (1) through the exploration of the casting process and try to use the peak (YF) with low dielectric constant microwave ceramic powder and hope (HP) ferrite powders were prepared with controllable thickness, good consistency, LTCC thick film material dense. And through the control of process parameters, preparation of thick film with different thickness. Built in situ optical dilatometer, and various forms of the Sintering Densification behavior of constrained LTCC thick film material was measured with vertical sintering sample stage and quartz. The swing arm (2) by film hanging vertical sintering method, several kinds of LTCC thick film materials were determined, DuPont 951 tape (DU), Ferro A6M tape (FE) YF thick film and uniaxial viscosity . through the study found that, by their own gravity, sintering densification behavior of LTCC thick vertical sintering in vertical direction is affected by the subtle effect, but its microstructures can still maintain uniaxial viscosity of isotropic.LTCC thick film with the increase of relative density is nonlinear growth, slow growth in the low density range in high density range, rapid growth. By comparison, the prediction of thick film experimental determination of uniaxial viscosity and Raj model results have good consistency. The In (Ep) and Arrhenius 1/T equation, solved the uniaxial viscosity of DU thick film activation energy, the value of 290. 47kJ/mol. (3) for anisotropic sintering parameters determination of LTCC thick film material, the design of single axial loading sintering experiment, FE thick film on vertical sintering applied uniaxial load, and by adjusting the uniaxial load size, to achieve the FE Zero shrinkage sintering of thick film in uniaxial direction. The study found that a single axle load can significantly change the loading direction on thick film material sintering densification behavior, but has little effect on the whole of the thick film sintering process. Through the study of uniaxial loading of FE thick film microstructure, porosity in thick film will gradually along the axis the loading direction in the sintering process, and the degree of orientation hole increases with uniaxial load increasing gradually. According to the corresponding thick film uniaxial zero shrinkage sintering boundary conditions simplified anisotropic continuum mechanics equation, successfully obtained for Sintering Parameter Calculation of thick film anisotropy formula, and calculated in the single axis under the condition of zero shrinkage of FE thick film uniaxial viscosity and viscous coefficient of Poisson's ratio. By comparing with the isotropic sintering parameters, uniaxial uniaxial zero shrinkage of sintered LTCC thick film 綺樺害鏄庢樉澧炲ぇ,鍚屾椂綺樻，

本文編號(hào)：1633234