干压成型制备高吸音多孔陶瓷及其性能研究

发布时间：2018-03-20 16:31

本文选题：干压成型　切入点：发泡剂　出处：《华南理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：利用多孔吸声陶瓷进行消声降噪是目前控制日益严重的噪声问题的主要方法之一,多孔吸声陶瓷具有强度高、耐高温、耐腐蚀等优点,应用前景广泛。本文以碳化硅为造孔剂或以碳化硅和氧化铁共同发泡,通过干压成型方法制备了多孔吸声陶瓷。首先,以陶瓷坯料、球土、烧滑石和钾长石作为基础原料,通过正交实验研究分析了各组分对多孔陶瓷的显气孔率、吸水率和体积密度的影响,选择其中显气孔率、吸水率高的试样配方作为本实验的基础配方,即陶瓷坯料55.00 wt.%,球土15.00 wt.%,烧滑石18.00 wt.%,钾长石12.00 wt.%;在此配方的基础上,研究了各原料在配方中的比例对制品性能的影响,并分别详细探讨了碳化硅添加量以及升温速率、保温时间、球磨时间、烧成温度和成型压力这些因素对制品显气孔率、体积密度和显微结构的影响;通过正交试验确定了最佳工艺参数:Si C添加量0.60 wt.%,升温速率6℃/min,保温时间25min,球磨时间84min,烧成温度1180℃,成型压力8MPa,在该优化条件下所制备的多孔吸声陶瓷性能为:显气孔率65.20%,吸水率101.50%,体积密度0.65,并在200~2000Hz的频率范围内,吸声系数于1600Hz处达到最大值0.53。在此基础上,研究利用氧化铁与碳化硅共同发泡来提高多孔陶瓷的吸声性能。分别探究了碳化硅与氧化铁的质量比、升温速率、烧成温度和成型压力对制品显气孔率、体积密度和显微结构的影响;对这些因素进行正交试验确定了最优方案为:碳化硅和氧化铁含量比1.6,升温速率6℃/min,成型压力10MPa,烧成温度1180℃。通过该方案制备了多孔吸声陶瓷,其显气孔率为77.20%,吸水率达到212.00wt%,体积密度0.37,而在200~2000Hz的频率范围内测试其吸声系数时,于1000Hz处达到最大值0.76,制品吸声系数比仅用碳化硅发泡制备试样高出约0.23。这说明此时制备的多孔吸声陶瓷的吸声性能得到显著提高,达到较高水平最后,为进一步提高制品吸声性能,探究了试样厚度和其背后空腔对吸声性能的影响,结果表明:适当的增加厚度和空腔厚度都有利于提高试样的低频吸声性能,且随这两者厚度的增加,试样吸声峰均出现向低频方向移动的现象。本文利用氧化铁与碳化硅共同发泡,通过干压成型法制备了吸声性能较好的多孔吸声陶瓷,为高吸音多孔陶瓷实现产业化生产提供了可参考的途径,具有重要的理论价值和实践指导意义。
[Abstract]:The use of porous ceramics for noise reduction is one of the main methods of noise control of the increasingly serious problem at present, the porous ceramics with high strength, high temperature resistance, corrosion resistance and other advantages, has broad application prospect. In this paper, silicon carbide or silicon carbide as the pore forming agent and ferric oxide to common foaming, by dry pressing method for preparing porous sound absorption ceramic. First, the ceramic blank, ball clay, talc and burning potassium feldspar as basic raw materials, through the orthogonal experimental study on the components of the porosity, water absorption effect and bulk density, the porosity, water absorption test formula with high basic formula for this experiment, i.e. ceramic ball clay 55 wt.%, 15 wt.%, 18 wt.% burn talc, potassium feldspar 12 wt.%; based on the formula of influence of the proportion of each raw material in the formulation of product performance, and Don't discuss silicon carbide content and heating rate, holding time, milling time, sintering temperature and forming pressure of these factors on porosity of products, influence of volume density and microstructure; through orthogonal test to determine the best process parameters: Si C dosage of 0.60 wt.%, the heating rate of 6 DEG /min, holding time 25min 84min, milling time, sintering temperature of 1180 DEG C, forming pressure 8MPa, under the optimal conditions of porous ceramic absorption properties were as follows: 65.20% porosity, water absorption rate of 101.50%, the volume density of 0.65, and in the 200~2000Hz frequency range, the sound absorption coefficient at 1600Hz reached the maximum value on the basis of 0.53. the research, using ferric oxide and silicon carbide foam together to improve the sound absorption properties of porous ceramics were investigated. The mass ratio of silicon carbide and iron oxide, heating rate, sintering temperature and molding pressure on the product porosity, body Effect of density and microstructure of the product; for these factors orthogonal test to determine the optimal scheme for silicon carbide and iron oxide content of more than 1.6, the heating rate of 6 DEG /min, 10MPa forming pressure and firing temperature of 1180 DEG C. Through the program preparation of porous ceramics, its porosity was 77.20%, water absorption rate of 212.00wt% 0.37, the volume density, test the sound absorption coefficient in the frequency range of 200~2000Hz to 1000Hz, reaches a maximum at 0.76, the absorption coefficient of samples than the products only with silicon carbide foaming higher than about 0.23. indicating that at this time the sound absorption properties of porous ceramics prepared by the sound absorption is greatly improved, finally reached a higher level, for to further improve the sound absorption performance of products, explores the effects of specimen thickness and the cavity, the sound absorption performance results show that properly increasing thickness and cavity thickness are beneficial to improving the low-frequency sound absorption of the samples Can, and with the increase in the thickness of the sample absorption peak appeared shifted to the low frequency phenomenon. This paper using iron oxide and silicon carbide together by dry porous ceramic foam, good sound absorption performance of the molding preparation, provides the way for high sound absorption of porous ceramic realize industrial production has important the theoretical value and practical significance.

【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ174.1

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