|About this Abstract
||Materials Science & Technology 2019
||Late News Poster Session
||P2-104: Study of the Kinetics of IMCs Precipitation during Solidification of an Al-Zn-Si-Mg Alloy, Using a Copper Wedge Mould Approach
||Abdul Khaliq, Daniel J. Parker, Nega Setargew, Ma Qian
|On-Site Speaker (Planned)
The precipitation of Fe-rich intermetallic compounds (IMCs, τ5c) is observed in 55%Al-Zn alloy coating pots during the hot-dip metal coating process. Temperature fluctuations in the coating alloy melt result in Fe dissolution from suspended IMCs/steel sheet and subsequent precipitation of the IMCs. These IMCs are source of metal spot defects in coated steel products and bottom dross build-up in the coating pot. This study investigated: (1) the effect of melt cooling rates from 650oC to 595oC and (2) the melt solidification to room temperature from 650oC and 595oC, on the precipitation of IMCs from an Al-Zn-Si-Mg alloy melt using a copper-wedge-mould. The results revealed that the alloy melt cooling during coating pot thermal cycles was ineffective to prevent IMCs precipitation. Hence, it is essential to minimise both the dissolution of Fe from the steel strip surface and temperature perturbations in the coating bath for reduced IMCs precipitation.