The research on phenolic resin modified by nanoparticles and used for magnesite-carbon brick binder
The research method use nanoparticles to modify the phenolic resin binder for magnesite-carbon brick. The normal detection indexes of phenolic resins is suited to used as the binder. FESEM images show that the nanoparticles are distributed uniformly without agglomeration almost. The physical-chemical property analyses show that the magnesite-carbon brick using this modified phenolic resin as binder possesses a low apparent porosity and a high bulk density and compression strength. Especially, the compression strength of the magnesite-carbon bricks after heat treatment for 200°C×12h increase to 43.94MPa and 41.35MPa, respectively. The results also show that with the increase of heat treatment temperature, the compression strength and the bulk density of magnesite-carbon bricks decrease and the apparent porosity magnesite-carbon bricks increases. The physical-chemical property shows a significant change from 200°C to 1100°C. However the change is not obviously from 1100°C to 1550°C and shows worse trend with the increase of heat treatment temperature.
INTERFACIAL STRENGTHES OF GLASS FIBER REINFORCED THERMOPLASTICCOMPOSITES AND ITS EFFECTS ON MECHANICAL PROPERTIES
Interfacial characteristics and effects on material properties as well as controllingof interfacial bonds were studied in the systems of BK-10 glass fiber reinforced PMMA and PCthermoplastic composites.Coating the fibers with organosilane coupling agents improves theinterfacial bonds and thus the mechanical properties of the composites.Four interfacial failuremodes exist in systems of brittle and ductile matrices with strong and weak interfacial bondsrespectively.Optical transparent composites can be made in systems with matching refractiveindices of matrix and reinforcing fiber by proper process controll.
Changes in Quartz During Heating and the Possible Effects on Si Production
In Si and FeSi production, the main Si source is SiO2, in the form of quartz. Reactions with SiO2 generate SiO gas that further reacts with SiC to Si. During heating, quartz will transform to other SiO2 modifications with cristobalite as the stable high-temperature phase. Transformation to cristobalite is a slow process. Its rate has been investigated for several industrial quartz sources and has been shown to vary considerably among the different quartz types. Other differences in behavior during heating between these quartz sources, such as softening temperature and volume expansion, have also been studied. The quartz-cristobalite ratio will affect the rate of reactions involving SiO2. The industrial consequences and other implications of the observed difference between quartz types are discussed. Initial studies of industrial quartz were published by Ringdalen et al. In the current work, a new experimental method has been developed, and an investigation of several new quartz sources has confirmed the earlier observed large variation between different sources. The repeatability of the data has been studied and the effect of gas atmosphere investigated. The results from the earlier work are included as a basis for the discussion.