On the Tendency of the Co-, Ni-, and Fe-Based Melts to the Bulk Amorphization

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Physical metallurgy and materials science, 2016-11, Vol.47 (11), p.5487-5495
• Main Authors: Sterkhova, Irina V., Lad’yanov, Vladimir I., Kamaeva, Larisa V., Umnova, Nadezhda V., Umnov, Pavel P.
• Format: Article
• Language: English
• Subjects: Alloys; Amorphization; Analysis; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystallization; Materials Science; Melts; Metallic Materials; Nanotechnology; Order disorder; Physical metallurgy; Quenching; Structural Materials; Studies; Supercooling; Surfaces and Interfaces; Temperature; Thin Films; Undercooling; Viscosity
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-016-3693-2

In this article, the influence of the liquid phase state on the glass-forming ability and solidification processes of the Co 65.5 Fe 6.5 Si 18 B 10 , Ni 64.4 Fe 4 Cr 4.9 Mn 2 B 16.2 C 0.5 Si 8 , and Fe 50 Cr 15 Mo 14 C 15 B 6 alloys was studied. It was shown that in conditions of quenching from the melt at ~10 3 K/s, the largest fraction of the amorphous phase is achieved by cooling from a narrow temperature range near 1573 K (1300 °C) for Co 65.5 Fe 6.5 Si 18 B 10 , 1503 K (1230 °C) for Ni 64.4 Fe 4 Cr 4.9 Mn 2 B 16.2 C 0.5 Si 8 , and 1653 K (1380 °C) for Fe 50 Cr 15 Mo 14 C 15 B 6 . It was found that at these temperatures, there are anomalies in the viscosity and undercooling polytherms caused by changes in short-range ordering in these melts. Overheating the Co 65.5 Fe 6.5 Si 18 B 10 , Ni 64.4 Fe 4 Cr 4.9 Mn 2 B 16.2 C 0.5 Si 8 , and Fe 50 Cr 15 Mo 14 C 15 B 6 melts above these temperatures is accompanied by changing the nature of their crystallization. It was shown that the analysis of the temperature dependences of undercooling and kinematic viscosity can be used to determine the optimum temperatures of the melts quenching to achieve their best bulk amorphization.