以凝膠法製備鋰鋁矽酸鹽玻璃陶瓷粉末及其燒結現象之研究

Abstract

本研究成功地以凝膠法製備鋰鋁矽酸鹽玻璃陶瓷(LAS)所需的粉體;粉體的 製備是利用醇基金屬的水合(hydrolysis)以及聚合(polymerization)後所 獲得,這些金屬包括甲醇基鋰,三異丁醇基鋁(ASB)與四乙醇基矽(TEOS).在 水合過程中,添加的水量以及酸鹼值均可有效地控制子的成長,得到不同大 小的粒子.將粉體經過冷均壓(cippingg)之後,以不同溫度進行燒結,可獲 得下列兩種結晶體:鋰霞石(eucryptite)和鋰輝石(spodumene).鋰霞石的 熱膨脹係數為-10x10-6C,而鋰輝石的熱膨脹係數為0.9x10-6C,調節試片中 鋰霞石與鋰輝石的含量,得到多種低膨賬係數甚至零膨脹係數的材質。結 晶相的析出,是以X-射線繞射圖形鑑定。 The research successfully produce LAS powders by sol-gel process. These powders have been prepared by hydrolysis and polymerization of the following metal alkoxides: lithium methoxide(LiOCH3), aluminum secondary buxide(ASB)(Al(C4H9O)3) and tetraethyl orthosilicate (TEOS)(Si(C2H5O)4). Different content of water during hydrolysis, as well particle size. Two crystallite phases could exist in the LAS systems investigated in this study. One is B-eucryptite, the other is B-spodumene. Thermal expansion coefficient of B-eucryptite is -10x10-6 C-1 and B-spondumene is 0.9x10-6 C-1. Controlling of sintering temperature could adjust the proportion of B-eucryptite and B- spondumene in sintered specimen. It is possible to obtain a proper thermal expansion coefficient of material by optimizing the proportion of the contents of B-eucryptite and B-spodumene in sintered specimen. The crystalllite phases were characterized by XRD.