| Canasite-based glass ceramics is a high toughness glass that its special microstructure has a large number of randomly oriented, interlocking blade-like crystals. It shows high tensile strength (281MPa) and high fracture toughness (4.8～5.2MPa·m1/2),even more than the high-strength Al2O3 ceramics(4～5MPa·m1/2).This glass has low melt viscosity and is easy to melt, can be carried out casting, pressing and rolling at the temperature of 950℃.It can also be used as a disk substrate material,because of its high strength,high toughness and other properties.It could have some of the biological activity and can be used as bone substitute biomaterials, by adding P2O5.But canasite-based glass ceramics have its weakness of low wear resistance, which will obstruct its further application.In order to find a way to improve the resistance of canasite-based glass ceramics, theB4C was added in this article to make the material densification to meet the application demands.The preparation methods of B4C and its composites are summarized in this article. According to own characteristic of B4 C, phase diagram of SiO2-CaO-CaF2 and the aim of experiment, SiO2-CaO-Na2O-K2O-CaF2 glass ceramic was used as the binder of B4 C, new composite was made through quickly sintering at low temperature and in normal atmosphere.In this experiment, basic glass frit was prepared by quenching the melted frit in cold water, and analyzed the properties of frit through DTA, XRD. This kind of glass ceramic with cuspidine as its main phase was prepared by heat treatment, and its thermal expansion coefficient matched B4C.And the influence of basic frit component, sintering temperature, dwelling time, basic frit proportion on the apparent porosity of the composites was researched by orthogonal experiment.According to the intuitionistic and variance analysis, basic frit proportion was the main factor that influenced the apparent porosity of the composites.SEM, XRD and EDS analysis indicated that composites were composed of rod-like cuspidine phase, B4C phase and glass phase. The influence rules of preparation process factors to apparent porosity and phase species of the composites were also studied and analyzed, thus the optimal preparation process was made sure.Finally, the apparent porosity of optimal sample bending strength, impact toughness, abrasive resistance and Vickers microhardness of the optimal samples were tested. Test results as followes:the average value of bending strength was 161.6MPa, the value of toughness was 3.8 Mpa-m1/2, the wear rate was 0.106×10-6mm3/N-m, the abrasive resistance was good.
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