|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals and Materials 2021
||Effects of Microstructural Features on the Crack Initiation Mechanism in AA6451 during Three-point Bending
||Yung Suk Yoo, Sazol Das, Richard Hamerton, Josh Kacher
|On-Site Speaker (Planned)
||Yung Suk Yoo
Aluminum alloys’ low density and high strength-to-weight ratio makes them an ideal candidate for automotive industries. The variety of alloying elements and processing produces complex microstructures that deform heterogeneously under different loading conditions. To better understand the failure mechanism of aluminum alloys, this work explores the effects of secondary phase particles and grain boundaries on crack initiation mechanism during bending.
In this study, AA6451, used as outer door panels in cars, was subjected to three-point bending to simulate hemming with inner door panels. Post-mortem scanning electron microscopy, focused ion beam (FIB) cross-section, and electron backscatter diffraction were combined to identify defects that exhibit localized deformation leading to cracking and determine the chronology of the crack initiation process. FIB lift-out specimens were extracted from regions of interest, and transmission Kikuchi diffraction and scanning transmission electron microscopy were used to study the evolution of defect structures that accompany localized deformation.