Pore structure design and grinding performance of porous metal-bonded CBN abrasive wheels fabricated by vacuum sintering

摘要

Porous metal-bonded cubic boron nitride (CBN) grinding wheels associated with desired porosity and excellent mechanical property are fabricated by employing alumina bubbles as pore-forming agents. The pore structures, including pore size, concentration and distribution, are optimised and correlated with the flexural strength of metallic porous composites. Characterisation of morphologies, such as microstructure, pore structures and grain morphology, is performed. The grinding performance, including grinding force, force ratio, grinding temperature, specific grinding energy and ground surface quality, with the porous CBN wheels and a vitrified CBN wheel is evaluated. Experimental results indicate that porous CBN wheels exhibit controllable pore structures, porosity and promising comprehensive grinding performance. In comparison with the vitrified wheel, a higher material removal rate and lower ground surface hardness can be achieved by porous wheels under the same conditions.