Li_2O加入量对Li_2O-Al_2O_3-SiO_2微晶玻璃结合剂性能的影响

Influence of Li_2O Addition on the Performance of Li_2O-Al_2O_3-SiO_2 Microcrystalline Glass Bond

采用石英粉(99%)、白刚玉、分析纯的硼酸、磷酸二氢氨、碳酸锂、氧化锌为原料,用TiO_2和ZrO_2为复合晶核剂,Li_2O的质量分数分别为5%、7%、9%、11%,原料混合均匀后高温熔炼成玻璃,水淬后球磨成玻璃粉,压制成型后通过烧结制备用于cBN砂轮的微晶玻璃结合剂。通过差热、XRD、SEM分析,结果表明不同含量的Li_2O在相应的热处理后均能够微晶化,能够生成大量晶粒细小而且分布均匀的锂辉石晶体。Li_2O含量为7%时微晶玻璃结合剂的强度最大,可以用于cBN砂轮制备时作为结合剂。

A mixture of quartz（99%）,Al_2O_3,Li_2CO_3,ZnO,H_3BO_3,NH_4H_2PO_4（raw materials）and TiO_2,ZrO_2（compound nucleating agent）with separately 5%,7%,9%and11% Li_2O has been melted at high temperature into glass and then ball-milled into glass powder after water quenching.After compression moulding and sintering,the powders are used as microcrystalline glass bond for cBN grinding wheel.Differential thermal analysis,X-Ray diffraction and SEM analysis indicate that the powder with different content of Li_2O can generate large amount of fine and evenly distributed triphane crystals after corresponding heat treatment.The microcrystalline glass bond has the maximum strength when the Li_2O content is 7% which can be adopted as bond for cBN grinding wheel preparation.