Vitrified bond grinding wheels have a porosity of less than 2%.
In the manufacturing process of vitrified bond grinding wheels, hot pressing technology is used to create high-density tools. Low-porosity grinding wheels can be produced by treating diamonds with hot pressing. In this process, the use of graphite molds allows higher sintering temperatures during hot pressing. Although the strength of graphite molds is lower, the densification of the grinding wheel can be achieved by controlling the heating temperature and pressing pressure. During the drying or degreasing stage, the water expelled from the temporary binder further reduces the porosity of the grinding wheel. Finally, after the sintering process, the bond components melt and flow around the abrasive, forming a porosity of less than 2%.