Effect of Casting Temperature on the Microstructure and Mechanical Properties of Cu-10Pb-10Sn/42CrMoS4 Bimetallic Hydraulic Cylinder Block

The CuPb10Sn10/42CrMoS4 bimetallic hydraulic cylinder block was manufactured in a continuous furnace, while the microstructure evolution and mechanical properties at different casting temperatures were studied. In this investigation, the casting temperature was divided into heating temperature and solidification temperature, whose temperature range was determined by the Thermo-calc software and differential scanning calorimetry. It showed that the heating temperature ranges from 1030 to 1100 degrees C and the solidification temperature should be higher than 950 degrees C. The microstructures and mechanical properties of matrix and interface were characterized by a series of analytical equipment. With increasing solidification temperature from 950 to 1050 degrees C, the morphology of Pb-rich secondary phase particles (SPPs) evolved from a continuous network structure to a dispersed rod-like structure. The size and distribution of SPPs were the best when the solidification temperature was 1000 degrees C, while the distribution of SPPs is becoming more and more uniform with increasing heating temperature from 1030 to 1100 degrees C. The heating temperature is the key role on the Cu/Fe diffusion layer thickness and interface bonding strength. At heating temperature of 1100 degrees C and solidification temperature of 1000 degrees C, the Cu/Fe diffusion layer thickness was 5.592 mu m and the interface shear strength was higher than 168 MPa.