|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
||Origins of Weak Strengthening Effect in As-cast Al-Si Alloys
||Wenqian Wu, Mingyu Gong, Bingqiang Wei, Amit Misra, Jian Wang
|On-Site Speaker (Planned)
Al-Si casting alloys are usually composed of α-Al and eutectic mixture of Al-Si with Si flakes. The Si and Al matrix generally hold cube-on-cube orientation relationship with the (111)Al||(111)Si interface. Several conventional strategies, such as modifying the geometry, size or distribution of Si flakes, are used to tailor mechanical properties of Al-Si casting alloys. However, the strengthening effect of Si flakes is very limited. Using molecular dynamics simulations, we revealed that the weak shear resistance of Al-Si interface, the low formation energy and migration energy of point defects in Al-Si interface can be origins of weak strengthening effect of Si flakes in Al-Si casting alloys. Our results show that the weak shear of the interface is due to easy glide of interface misfit dislocations, and weak strengthening effect is due to easy cross-slip and climb of lattice dislocations at interfaces.
||Modeling and Simulation, Aluminum, Thin Films and Interfaces