Effects of C and Cr contents on microstructure and physical properties of powder forged Fe–Cu–C–Cr alloys

The effects of C and Cr contents on the microstructure and physical properties of the powder forged Fe–Cu–C–Cr alloys were studied by changing the mass fraction of C and Cr elements. The results show that, the microstructures of the alloys are mainly composed of ferrite and cementite without Cr element, and the hardness and tensile strength of the alloys increase slightly with the increase of C content, showing little effect on the final friction coefficient of the alloys. After adding the Cr element, the alloy density decreases and the microstructure is more complex. The alloy hardness increases with the increase of Cr content, up to HRA 68.6. The high temperature tensile strength of the alloys is influenced by C and Cr, the tensile strength of Fe–2Cu–0.5C–5Cr is the highest (378 MPa). The friction coefficient of the alloys decreases with the increase of Cr content. When the mass fraction of Cr is 10%, the final friction coefficient is 0.195, the wear mode is mainly oxidation wear with a small amount of abrasive wear.