|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses XIII
||Synthesis of Bulk Amorphous Co-C Alloys
||Hesham Elmkharram, A. O. Aning
|On-Site Speaker (Planned)
Amorphous Co-C alloys with compositions of up to 20 at% C were synthesized from elemental Co and C (graphite) using mechanical alloying. Amorphization began early in the milling process – within 5 h for compositions of 10 at% C and above. All of the alloys became amorphous after 40 h of milling in a SPEX mill, even though the relative negative heat of mixing which is related to the driving force for amorphization is as small as -2 kcal/mol., as predicted by the Miedema model, for the Co-5 at% C alloy. The amorphous phase crystallization temperature increased with milling time for all of the alloys. However, it decreased linearly with increased composition for a given milling time. Spark plasma sintering at 260OC yielded a 90 % dense bulk amorphous material with a hardness of 420 HV.
||Planned: A print-only volume