Crystalline-to-amorphous phase transformation in mechanically alloyed Fe{sub 50}W{sub 50} powders
- Tohoku Univ., Sendai (Japan). Inst. for Materials Research
A mechanical alloying process via a ball milling technique has been applied for preparing amorphous Fe{sub 50}W{sub 50} alloy powders. The results have shown that during the first and second stages of milling (0 to 360 ks) W atoms emigrate to Fe lattices to form nanocrystalline b.c.c. Fe-W solid solution, with a grain size of about 7 nm in diameter. After 720 ks of the milling time, this solid solution was transformed to an amorphous Fe-W alloy coexisting with the residual fraction of the unprocessed W powders. During the last stage of milling (720 to 1,440 ks) all of this residual W powder reacts with the amorphous phase to form a homogeneous Fe{sub 50}W{sub 50} amorphous alloy. The crystallization temperature and the enthalpy change of crystallization of amorphous Fe{sub 50}W{sub 50} powders milled for 1,440 ks were measured to be 860 K and {minus}9kJ/mol, respectively. The amorphous Fe{sub 50}W{sub 50} powder produced is almost paramagnetic at room temperature. The powder comprises homogeneous and smooth spheres with an average size of about 0.5 {micro}m in diameter.
- OSTI ID:
- 483631
- Journal Information:
- Acta Materialia, Journal Name: Acta Materialia Journal Issue: 3 Vol. 45; ISSN 1359-6454; ISSN ACMAFD
- Country of Publication:
- United States
- Language:
- English
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