|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Solid State Diffusion Bonding of Metals and Alloys
||Multi-Scale Study Of Bonding Mechanism Between Immiscible Mg/Steel Alloys
||Jiahao Cheng, Xiaohua Hu, Xin Sun, Vivek Anupam, Glenn Daehn, David Cullen
|On-Site Speaker (Planned)
Vaporizing foil actuator spot welding method is used to join magnesium alloy AZ31 and uncoated high-strength-steel DP590, which are typically considered as unweldable due to high physical property disparities, low mutual solubility, and none-existence of intermetallic phases. SEM and HRTEM characterization of the weld interface found the impact creates an Mg nanocrystalline inter-lay with abundant Fe particles. The inter-lay exhibits intact bonding with both DP590 and AZ31 substrates. To understand the underlying mechanisms, finite element-based process simulation and subsequent molecular dynamics (MD) simulations are conducted to study the impact and cooling processes at different location of the interface. The results found the inter-layer formation is through impact induced mechanical “mixing”, and segregation of Fe atoms during the rapid cooling. At last, MD simulation compares the impact-induced immiscible materials interface with DC resistance spot welding induced interface, explaining the difference in the bond strength anticipated for the different joining methods.
||Planned: Supplemental Proceedings volume