Investigation of Effect of Compact Pressure on Shaping and Microstructure of Cu-10Sn-10Pb

In this paper the influence of green density in shaping and microstructure of sintered specimens was studied. Cu-10Sn-10Pb samples were compacted in 400MPa and 100MPa and were sintered at the range of 890-970°C for 20 min. The in situ images from the samples for measuring dimensional changes were taken at various sintering temperatures. It is concluded that 100MPa compacted samples have less distortion due to low liquid phase formation and keep their shape even at higher temperatures. In these samples, less contact between the solid particles has been caused low liquid phase formation. In this condition, fragmentation and then rearrangement of bronze particles as main and effective factors of densification are occurred. Moreover, liquid phase of lead which is formed in the microstructure has less diffusion through to the grain boundaries and preventing more distortion. For these reasons elephant foot phenomenon was not appeared in 100 MPa compact even at high temperatures.