# Grinding Deformation Behavior of a Lamellar γ-TiAl Alloy

## TL;DR

This paper studies how a specific titanium aluminide alloy deforms during grinding, revealing how surface structures bend and change based on grinding parameters.

## Contribution

The study provides new insights into the deformation mechanisms of lamellar γ-TiAl alloys during grinding, including the bending behavior and deformation zones.

## Key findings

- Surface lamellae bend during grinding, with bending angle φ influenced by lamellae orientation relative to grinding direction and surface normal.
- Grinding depth primarily controls the lamellar deformation depth h.
- Three distinct surface zones are identified: fine-equiaxed grain zone, bending lamella zone, and near-surface deformation zone with dislocation tangles.

## Abstract

γ-TiAl alloys are susceptible to surface damage during grinding, deteriorating their mechanical properties during service. However, the underlying mechanism of surface microstructure deformation during grinding remains incompletely understood. This work systematically investigated the deformation behavior of surface lamellae in a Ti-45Al-2Nb-2Mn-1B (at.%) alloy during grinding. The surface lamellae exhibit bending after grinding, with the degree of bending angle φ depending on the orientation of the lamellae. The bending angle φ depends on both the angle between the lamellae interface normal and the grinding direction, and the angle between the lamellae interface normal and the grinding surface normal. The lamellar deformation depth h is primarily governed by the grinding depth. The surface of the sample after grinding can be divided into three distinct layers: a surface fine-equiaxed grain zone, a bending lamella zone, and a near-surface deformation zone. The deformation in the bending lamella zone primarily results from slip bands and stacking faults, whereas the near-surface deformation zone contains extensive dislocation tangles. The results offer fundamental insights into the deformation mechanism of surface lamellar colonies during grinding and provide theoretical guidance for the machining of γ-TiAl alloy components.