| Ceramic-glass for its unique thermal stability, excellent mechanical strength etc. It have been used in mechanical engineering, building decoration materials, military-installations, biological medicine, electronic industries high-tech fields. This article studies Al2O3-SiO2, MgO-Al2Oc-SiO2 two system, and take sol-gel method to pruduce precursory powder, and take Spark Plasma Sintering(SPS)/Hot Pressing(HP) two kinds of sintering process. Proclaim that SPS as a method of non-equilibrium state rapid preparation have differences on Product of crystal and microstructure compare to HP sintering process.As to powder fabrication, In order to obtain high uniformity and powder of high purity, I prefer to use sol-gel process. Compared to traditional method this method can lower sintering temperature, expand its range of components, this method can produce some materials that conventional method cannot do. This studies take Six water nitric acid magnesium(Mg(NO3)2·6H2O). Aluminium ethoxide(Al(OC2H5)3). tetraethylorthosilicate(Si(OC2H5)4) as precursor. Firstly, put the precursor in Alcohol at 60℃, uniform mixing for 10h and I can got Al2O3-SiO2, MgO-Al2O3-SiO2 mixed gel, then dry it at 100℃, mill it into powder and put it to electric furnace for Preliminary heat treatment,and I analysis the different Product components and Reaction mechanism of Al2O3—SiO2 and MgO-Al2O3-SiO2 system at different temperature. I also study two system data of differential thermal analysis, find that crystal water and organic matter of precursory powder burn out completely at 300℃. So I take powder treated at 300℃as precursor of producing bulk sample. In order to identify no crystallization of precursor I analysis XRD and TEM picture.As to bulk fabrication, my study mainly use Spark Plasma Sintering(SPS)/Hot Pressing(HP) sintering. Compared to SPS, HP is a sintering process that warming and cooling slowly, tiny nuclei have long enough growth time, so the crystallization in HP is bigger than SPS. The chemical composition of the powder do not change at all after preliminary heat treatment at 300℃, so I finish producing powder and bulk at one step. Because compare to conventional sintering method there is greatly difference, at the beginning of producing Ternary system bulk confront many difficulties, after testing different temperature regime and pressure regime, I find out the HP sintering can get density bulk at 1300℃,30Mpa. Lower temperature cannot form a bulk, however, high temperature cause glass ingredient to melt, also can not form a bulk. I can get bulk through SPS at 1300℃,30Mpa, higher or lower temperature will cause same problems as I noted above. Because SPS has strong current, it can ignite particle activity and lower chemical reaction temperature. The sintering temperature of SPS of Ternary system is 150℃lower than HP.As to bulk characterization. I take X-ray diffraction(XRD), Infrared spectroscopy(FT-IR), Scanning electron microscopy(SEM) method. In binary system, bulks of SPS and HP present different microstructure and same ingredient. In ternary system, bulks of SPS and HP present different microstructure and ingredient.
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