Influence of hot pressing temperature on the microstructure and mechanical properties of 75% Cu-25% Sn alloy

The alloy of 75% Cu-25% Sn was utilised and hot-pressed for 4 min at 421, 520 and 600 degrees C to obtain a self-sharpening bond for diamond honing stones at low sintering temperature. Densification and mechanical tests were performed, and structures were investigated by X-ray diffraction, energy dispersive spectroscopy and scanning electron microscopy. Results showed that the porous structures changed into microporous structures when the hot pressing temperature was increased from 421 degrees C to 600 degrees C. The mechanical properties improved from HRB 79.1 to HRB 105.1 in hardness and from 104.2 MPa to 201.4 MPa in transverse rupture strength. After hot pressing at 600 degrees C, the microstructure consisted of alpha(Cu) + delta eutectoid and micropores, which meets the requirements of bonds for honing stones. (C) 2013 Elsevier Ltd. All rights reserved.