Study on the Microstructure, Wear, and Corrosion Resistance of W, Ni, and Co-Doped Fe-Alloys Processed by Solid-State Sintering

Abstract

Iron-based alloys with compositions Fe 3 CWNi, Fe 3 C10WCo, and Fe 3 CWNiCo were synthesized by solid-state sintering at 1400 °C. This study investigates how additions of nickel (Ni), cobalt (Co), and tungsten (W) enhance the microstructure, wear resistance, and corrosion behavior of the prepared alloys. Microstructural characterization reveals a clear improvement in phase homogeneity and grain refinement, particularly in Ni-containing alloys, resulting in a mechanically stronger and more stable matrix. Tribological tests conducted under applied loads of 5 and 10 N and a sliding speed of 0.03 m·s -1 demonstrate that alloying significantly improves wear performance. The WNi doped alloy exhibits the most notable enhancements, showing a reduced friction coefficient of 0.42 and a markedly lower wear rate of 2.8 × 10 -5 mm 3 ·N -1 ·m -1 . Surface analysis reveals the formation of compact, well-adherent passive films that significantly enhance corrosion resistance through an effective barrier mechanism. The dominant wear mechanisms abrasive wear, oxidative wear, and fatigue-induced surface degradation are significantly mitigated due to the synergistic action of Ni and W. This synergy promotes the formation of stable oxide layers, improves load-bearing capacity, and reduces material loss during sliding. The prepared Fe 3 CWNiCo alloy shows substantial improvements in mechanical durability, chemical stability, and surface protection compared to the other compositions. These findings demonstrate that the developed alloys are strong candidates for demanding service environments, particularly in mechanical and aerospace applications where superior wear and corrosion resistance are essential.