Stacking Fault in Non-Close Packed System- Role of Interstitials at Pentahedron Voids in WC Simple Hexagonal

TL;DR

This paper investigates the atomistic mechanisms behind stacking faults in non-close packed tungsten carbide, highlighting the role of interstitials at pentahedron voids and providing experimental and theoretical insights into defect behavior.

Contribution

It introduces a new atomistic model for stacking faults in WC and links interstitial carbon ordering to defect rotation axes, expanding understanding of non-close packed systems.

Findings

Identified the type of stacking fault in WC.

Established the role of interstitials at pentahedron voids.

Supported the model with experimental evidence.

Abstract

Atomistic origin of stacking faults in non-close packed systems is a fundamentally distinct mechanism from the well-known close packed structures with ABC stacking, and represents an uncharted territory in material research. According to experimental data, stacking faults in simple hexagonal WC happen in {1-100} planes that are packed rectangularly and have ABAB stacking. This work identified the type of the defect and crystallographic behaviour by creating energetically relaxed potential atomistic models of stacking faults in WC. Experimental evidence supporting the rotation axis along stacking fault caused by variation in carbon ordering at the interstitial site has been established, in accordance with the theoretical model.