Effect of impurities on growth and morphology of cementite nanowires

TL;DR

This study uses first-principles calculations to investigate how various impurities influence the growth, morphology, and stability of cementite nanowires, revealing impurity-induced changes in formation energies and growth directions.

Contribution

It provides new insights into impurity effects on cementite nanowire morphology and stability, which were not previously understood.

Findings

Impurities decrease formation energy of cementite nanowires.

Impurities can alter the preferred growth axis of nanowires.

Conditions for formation and decomposition of cementite nanowires are discussed.

Abstract

Effects of doping on morphology of iron carbide (cementite) nanowires have been explored by first principle electronic structure calculations. We examined the role of several realistic impurities (Si, Mn, V, P and S) in the formation energies of the cementite nanowires with different sizes and morphologies. It is shown that the presence of the impurities decreases the formation energy and can switch the preferable axis of the cementite nanowire growth. The conditions of the formation and decomposition of cementite nanowires in steels are also discussed.