Effects of RE (Nd, Ce, Y, La) on TiC(100)/Fe(110) interface based on first-principles calculations

Abstract

The effects of rare earth elements (Nd, Ce, Y, La) on the bonding strength and stability of the TiC(100)/Fe(110) interface were studied based on first-principles calculations. The calculation of the surface energy of the low-index surface of the bulk phase shows that the TiC(100) and Fe(110) sections are the two sections with the lowest surface energy in the two bulk phases, respectively. The calculation of the interface shows that in the five interface models, the formed interface can exist stably, but the bonding strength is not high, and the interface is the weak point of TiC/Fe matrix composites. The calculation of the rare earth doped interface shows that when Fe atoms are substituted, γ-Ce (−5.30454 J/m2), γ-Y (−5.28015 J/m2), γ-La (−5.22953 J/m2), γ-Nd (−5.22545 J/m2); when Ti atoms are substituted, γ-Ce (−4.00834 J/m2), γ-Y (−4.03247 J/m2), γ-La (−3.96345 J/m2), γ-Nd (−3.91418 J/m2). The addition of the four rare earth elements can reduce the interfacial energy of the interface and increase the stability of the interface, thereby increasing the properties (hardness, wear resistance, strength, etc.) of TiC/Fe matrix composites. When the Ce element-doped interface replaces Fe atoms, the enhancement effect on the interface is stronger.