|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Surface Interactions in Materials
||Effects of Surface Layer Oxides on Spark Plasma Sintering of an Al-Mg Alloy Powder
||Clara Hofmeister, Frank Kellogg, Scott Walck, Anit Giri, Brandon McWilliams, Kyu Cho
|On-Site Speaker (Planned)
Spark Plasma Sintering (SPS) uses large electrical currents to rapidly heat and consolidate powder. By using insulating dies, the current is forced to travel only through the powder bed, leading to faster heating rates. In previous work, it was found that while as-atomized AA5083 powder was insulating at temperatures below 300°C, cryomilled AA5083 was conductive at all processing temperatures. The change in conductivity may have occurred through the presence of graphite (introduced as a processing aid during cryomilling) or through alterations to the native oxide layer. Scanning transmission electron microscopy coupled with electron energy loss spectroscopy was employed to investigate the chemistry, structure and thickness of the native oxide layer of both the as-atomized and cryomilled AA5083 powders. Gas fusion and thermal conductivity analysis was used to quantify the chemistry differences. This study investigates changes to the powder caused by the cryomilling process that may cause the development of conductivity.
||Planned: Supplemental Proceedings volume