Low-temperature Synthesis of xCaO-SiO2 Powders

• Main Authors: Kun-ying Wang, 王坤應
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/36983733278372786255

碩士 === 國立聯合大學 === 材料科學工程學系碩士班 === 94 === The main purpose of this research is to adopt ultrasonic synthesis method (contact and non-contact types) to synthesize the main constituents xCaO．SiO2 powder of the traditional cement material. It is tried on solid and liquid raw materials to synthesize the xCaO．SiO2 powders. The characteristics of xCaO．SiO2 powders was analyzed by differential thermal analysis(DTA), X-rays diffraction analysis (XRD), fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The synthetic temperation can be lowed from 1200 ℃ to 1000 ℃, when the Bacl2 content reaches above 3.33 mol% in the process by using crystalline raw materials. In the process by using liquid raw materials, the xCaO．SiO2 powders can be synthesized at 800 ℃ by contact type ultrasonic irradiation. In the process by using amorphous raw materials (30 wt% CaO modified fly-ash glasses), the xCaO．SiO2 powders will form in the amorphous matrix at 800 ℃. When the calcined temperature above 1000 ℃, the gehlenite (Ca2Al2SiO7) crystals can be formed and become the dominate phase in all the CaO-modified fly-ash glasses.