| This paper mainly focuses on two purposes: preparing porous vitrified bond with high strength, and managing to controll the porosity and the morphology of pores in the vitrified bond.The vitrified bond was prepared by cold pressing and sintering method using borosilicate, mineral A and white corundum as raw materials. Bending strength of vitrified bond was measured by three-point bending. XRD and stereomicroscope were carried to investigate the phase structure and the morphology of the pores. The relationship between the content of B2O3 and the bending strength of the vitrified bond which contains boron glass was established. The effects of sintering temperature, the contents and sizes of the pore former on the porosity and the morphology of pores were investigated.The experimental results show that high-strength vitrified bond whose main chemical components were B2O3, SiO2 and Al2O3 was obtained after sintering at the temperature of 900 oC for 2 hours. The bending strength reached 113.0MPa. With the increasing the B2O3 content, the bending strength tended to increase and then decrease. The optimum ratios of R2O/B2O3=0.98 and B2O3/SiO2=0.52. No chemical reaction was found when diamond grits added into the vitrified bond, showing that the bond was suitable for preparing the vitrified bond diamond tools.The spherical-like pores with the diameters of 100~600μm distributed uniformly in the bond when using marble as pore former. The porosity and the sizes of the pores depended on the sintering temperature, the content and granularity of the pore former. At the same sintering temperature and content, the results indicated that the porosity of the vitrified bond increased as the granularity of pore former decreased, while the strength of the bond induced a little bit.
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