Microstructure and mechanical properties of ceramic particle-reinforced powder metallurgy Fe-2Cu-0.6C composites

Ceramic particle-reinforced Fe-2Cu-0.6C low-alloy steel composites (SiC, TiC, and TiB₂ ceramic particles in the mass fraction of 0~1.6%) were prepared by the conventional powder pressing/sintering technology at 600 MPa and 1140℃, the microstructures and mechanical properties of composites were investigated. The results show a good interface bonding between the reinforced particles (SiC and TiB₂) and the matrix because of the reaction during sintering. The Brinell hardness and tensile strength of the sintered composites added with 1.6% SiC particles by mass increase by 35.9% and 69.4%, respectively, compared with those of Fe-2Cu-0.6C matrix. When 1.2% TiB₂ particles by mass are introduced, the hardness and tensile strength of the sintered composites increase by 77.9% and 72.6%, respectively, compared with those of the matrix. Meanwhile, it is noted that the relative density of the TiB₂-reinforced low-alloy steel composite also increases by 5.3%. The addition of TiC particles has little effect on the Brinell hardness and tensile strength of the composites due to no reaction between TiC particles and the matrix.