氮化硅陶瓷低温烧结助剂研究进展OA

Silicon nitride ceramics have excellent properties,but because of its strong covalent bond and small self-diffusion coefficient,it is difficult to sintering.At present,high performance silicon nitride ceramics are mainly pre-pared by high-temperature pressure sintering method,sintering temperature is above 1 800℃,which requires high equipment and preparation cost,limiting the practical application of silicon nitride ceramics.As one of the effective ways to reduce the production cost of silicon nitride,low temperature sintering has been widely concerned.At present,the research on the low-temperature sintering of silicon nitride ceramics at home and abroad mainly focuses on the selection of sintering additives,which can be divided into two categories:the use of sintering additives with low eutec-tic temperature of SiO2 and the use of multi-component sintering additives.The research progress of these two kinds of low-temperature sintering auxiliaries is reviewed,and a reasonable scheme for the selection of low-temperature sinte-ring auxiliaries is proposed.In summary,in order to produce silicon nitride ceramics with good performance at low temperatures,it is necessary to choose asintering agent with low eutectic point with SiO2,and use multiple-compo-nents control to regulate the microstructure and properties of silicon nitride ceramics.