Formation and crystallization of Al–Ni–Ti amorphous alloys

✍ Scribed by D.H. Kim; W.T. Kim; D.H. Kim

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 644 KB
• Volume: 385
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2004.04.016

✦ Synopsis

Formation and crystallization behaviors of the Al-Ni-Ti amorphous alloys have been investigated in the present study. Among the amorphous alloy compositions investigated in the present study, only Al 87.5 Ni 10 Ti 2.5 alloy composition exhibits a good ductility, i.e. 180 • bending without fracture, indicating that the ductility of the Al-Ni-Ti amorphous alloys is strongly dependent on the alloy composition. Improved ductility can be obtained only when a few nanometer size Al crystals are embedded in the amorphous matrix. The amorphous Al-Ni-Ti alloys crystallize by either primary crystallization of nanometer-sized fcc-Al phase or by the simultaneous precipitation of fcc-Al and metastable intermetallic compound. The Al-Ni-Ti amorphous alloy showing the bending ductility crystallizes by diffusion-controlled growth of quenched-in Al crystals. On the other hand, the Al-Ni-Ti amorphous alloy without bending ductility crystallizes by diffusion-controlled nucleation and growth process.