An as-cast ingot was used for rapid solidification and high energy ball milling in order to synthesize amorphous and/or nanocrystalline (Al4Cu9)94.5Cr5.5 γ-brass alloy. Microstructure of the milled product has been characterized by X-ray diffraction, differential scanning calorimetry, high-resolution transmission electron microscopy and energy dispersive X-ray spectroscopy. Rapid solidification by melt spinning produces nanocrystalline aggregate of size ∼40 nm and mechanical milling of the alloy up to 50 h yields a composite microstructure comprising of amorphous and nanocrystalline phases, with crystallite size in the range of 15-25 nm. No other metastable phases have been identified. Attempts have been made to understand the possibility of formation of amorphous phase through mechanical milling using semi-empirical model of Miedema.
Bibliographical noteFunding Information:
The authors would like to thank Prof. S. Lele, Prof. S. Ranganathan, Prof. K. Chattopadhyay, Prof. G.V.S. Sastry and Dr. R.K. Mandal for many stimulating discussions and suggestions. A technical support for electron microscopy experiment by Ms. H.J. Chang is also appreciated. The financial support of the Department of Science and Technology (DST), New Delhi, India for carrying out this work is gratefully acknowledged.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry