|About this Abstract
||MS&T23: Materials Science & Technology
||Interface-mediated Phenomena in Structural Materials
||Interface Strengthening in As-cast and Laser-modified Al-Si Eutectic Alloys
||Wenqian Wu, Bingqiang Wei, Amit Misra, Jian Wang
|On-Site Speaker (Planned)
Al-Si cast alloys are usually composed of α-Al and Al-Si eutectic. Si flakes and Al matrix generally hold cube-on-cube orientation relationship with the primary interface (111)Al || (111)Si. Extensive experimental studies demonstrated that Si flakes cannot significantly improve mechanical properties of Al-Si cast alloys. 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. By processing as-cast alloy via laser rapid solidification (LRS) techniques, the coarse-grained Al-Si alloys can be refined into nanofibrous composite with Si nanofibers. LRS modified Al-Si alloys exhibit high strength, good plasticity, and high strain hardening rate. Atomistic simulations are used to explore dislocation mechanisms in nano-confined Al containing Si nanofibers. This work is funded by DOE, Office of Science, Office of Basic Energy Sciences with the grant number of DE-SC0016808.