| About this Abstract |
| Meeting |
MS&T22: Materials Science & Technology
|
| Symposium
|
Metal Powder Synthesis and Processing
|
| Presentation Title |
Mechanical Alloying and Thermal Stability of Amorphous Co-C Alloys |
| Author(s) |
Alex O. Aning, Hesham Elmkharram |
| On-Site Speaker (Planned) |
Hesham Elmkharram |
| Abstract Scope |
This work investigated the solid-state formation of Co-C amorphous alloys and their thermal stability. Amorphous Co-C alloys with compositions of 2 to 40 at% C were successfully synthesized using mechanical alloying. After 40 h of milling, complete amorphization was observed in all alloys, except for the 2 and 5 at% C alloys. Alloys with compositions through 20 at% C crystalized in two steps; the lower temperature event precipitated metastable carbide from the amorphous phase, followed by transformation to FCC cobalt and graphite from both the remaining amorphous and the metastable carbide at the higher temperature. Two types of carbides were observed - Co3C in the 2 and 5 at% C alloys, and Co2C in the higher carbon alloys through 20 at% C. For compositions above 20 at%, only one step crystallization was observed, that due to the decomposition of the amorphous phase to amorphous carbon and primarily FCC cobalt phase. |