Effect of Alumina Bubbles on Mechanical Properties and Microstructure of Metal Bond for Superabrasive Grinding Wheels

Effect of the pore size and volume fraction of alumina bubbles on the mechanical properties and microstructure of metal bond for superabrasive grinding wheels were studied by means of single factor test. The results showed that the mechanical strength reduced with the increase of bubble size and volume fraction of alumina bubbles. The morphology of the center section of the binder matrix showed that the higher the volume fraction of alumina bubbles was the less the effective area rate of the matrix was. Additionally, the bigger the bubble size was the more inhomogeneous the bubbles distributed. The pores generated after the fracture of the alumina bubbles had a regular shape and size which satisfied the chip space requirement of the wheels. At last, the failure condition of the bond matrix was established, which indicated that the strength of the bond matrix is mainly related to the effective area rate and the homogeneity of the bubble distribution.