Study Of LAS System Glass-ceramic As Abrasive Binder

LAS system as microcrystalline glass abrasive binder,with low thermal expansion coefficient,good thermal stability and chemical stability,high strength,through design and adjustment of composition,heat treatment process control,can be applied to a variety of all kinds of abrasive abrasive preparation.From choosing appropriate alkali metal materials,design and adjustment of basic glass composition,preparation of a glass melted at low temperature and low temperature abrasive firing of LAS microcrystalline glass,and applied to several different abrasive,determine the bond abrasive sintering temperature system is the focus of this study.In this paper,the glass-ceramic and abrasive binder type,development and preparation technology of a systematic review,emphatically introduces the Li2O-Al2O3-SiO2 of microcrystalline glass as abrasive binder performance and application of research.From abrasive superhard abrasive,in particular,the requirement of structure and performance of binder,choose to beta spodumene solid solution as the main crystal phase of LAS microcrystalline glass,with melting preparation of microcrystalline glass,and analyzes the structure and performance of sintering,the preparation of microcrystalline glass abrasive binder,analyze its mixed with abrasive burning application,determine the sintering temperature system.Part experimental results show that the introduced with carbonate Na2O and K2O can decrease the temperature of the melted glass,but crystallization effect is not good,after heat treatment of the sample have split phase phenomenon,and expected the uniform stability of the main crystal phase,and use phosphate and nitrate raw material,melted temperature rise slightly,but is good for microcrystalline glass crystallization.Over 8%B2O3 consumption still have good help fusion effect,and the effect on the thermal expansion coefficient is not big,can generate stable main crystal phase of LAS microcrystalline glass,the scope of its usage in 8-15.5%at the same time,by adjusting the dosage of alkali metal oxide(soil),which changes the thermal expansion coefficient,in 3.8?6.2×106/?,at this time of microcrystalline glass nucleation temperature is about 500?,the crystallization temperature is about 700?,is a good low melting glass-ceramic abrasive binder selection.By the application of binder and abrasive research shows that the series of different components of binder and several kinds of commonly used abrasive,such as white jade,green silicon carbide and synthetic diamond,with similar thermal expansion coefficient,good wettability.Abrasive samples of sintering temperature is 680?,holding time for 2 h,binder,abrasive,they captured the dextrin powder mass ratio of 25:75:2.5 and 30:70:3,samples of moderate porosity and bending strength is bigger.When the abrasive is green silicon carbide,the porosity can be reached 32.1%and 20.7%respectively,and the bending strength can reach 43.7 MPa and 45.8 MPa.