Elemental Doping-Induced Bonding Modulation at VC/Fe Interfaces

Area of Science:

• Materials Science
• Metallurgy
• Computational Materials Science

Background:

• Wear-resistant ferroalloys are crucial in demanding industries like mining and power generation.
• Carbide stability within the alloy matrix is vital for performance but often compromised under harsh conditions.
• The role of alloying element segregation at matrix-carbide interfaces in determining alloy stability is not fully understood.

Purpose of the Study:

• To investigate the influence of doping elements on the stability of the gamma-iron/vanadium carbide (γ-Fe/VC) interface in iron-based alloys.
• To elucidate the segregation behavior of various alloying elements at the interface.
• To provide theoretical insights for designing superior multicomponent ferroalloys.

Main Methods:

• Utilized first-principles calculations to model and analyze the γ-Fe/VC interface.
• Examined two representative interface configurations (top-site and 4-fold) to determine the most stable one.
• Systematically evaluated the effects of Cr, Mn, Mo, Ni, Si, and Ti dopants on interfacial stability.

Main Results:

• The top-site configuration was identified as the more stable interface model.
• Mo, Ni, and Si were found to preferentially segregate to the γ-Fe side, with Mo showing the most significant stabilizing effect.
• Ti demonstrated a strong carbide-forming tendency, enhancing atomic-scale bonding, while Cr and Mn had limited strengthening effects.

Conclusions:

• Alloying element segregation at the matrix-carbide interface critically influences the stability of wear-resistant ferroalloys.
• Elements like Mo, Ni, and Si can be strategically used to enhance interfacial bonding and overall alloy performance.
• This research offers a theoretical foundation for developing advanced, high-performance ferroalloys tailored for extreme environments.