| About this Abstract |
| Meeting |
2010 TMS Annual Meeting & Exhibition
|
| Symposium
|
Processing Materials for Properties
|
| Presentation Title |
Innovations in Processing of Lightweight Metal Matrix Composites |
| Author(s) |
Ramana G. Reddy |
| On-Site Speaker (Planned) |
Ramana G. Reddy |
| Abstract Scope |
Newly emerging chemical in situ process is economical and energy efficient for large scale manufacturing of particulate metal matrix composites compared to the conventional (physical ex situ) processes. This presentation concentrates on some of the key examples from the author’s experience and others, application of engineering fundamentals on the in situ processing of nanoparticulates of discontinuously reinforced Al and Mg alloys metal matrix composites. Aluminum and Magnesium alloys were reinforced with AlN nanoparticles using chemical in situ process. Thermodynamic analyses were made to identify the conditions for the in situ formation of the AlN in Al and Mg alloys. Effect of experimental processing parameters (i.e. time of gas injection, concentration of ammonia, and temperature of the melt) on the formation of AlN nanoparticles in alloy was determined. The AlN quantities in the composites varying from 5 to 51 wt % were produced. Increase in either injection time or flow rate of the ammonia gas increased the nitride content. AlN particles with an average size of 400 nm were produced. The measured Vickers hardness of the composites formed increased with increasing AlN content. The amount of AlN experimentally formed is in good agreement with the thermodynamically predicted data. A kinetic rate equation of in situ formation of AlN nanoparticulates in lightweight metal matrix composites was developed. A possible reaction mechanism of AlN formation was proposed. The industrial applications of this in situ manufacturing of composites by molten metal technology were discussed. |
| Proceedings Inclusion? |
Definite: A CD-only volume |