Interdiffusion study of the topologically closed packed μ phase and the phase boundary compositions in the Fe–Mo system. (October 2019)

• Record Type: Journal Article
• Authors: Baheti, Varun A.; Raju, Ravi
• Is Part Of: Intermetallics. Volume 113(2019:Oct.)
• Publication Date: 2019-10
• Subjects: Intermetallics -- Diffusion -- Heat treatment -- Joining (diffusion–bonding) -- Electron microprobe -- Scanning electron microscopy; Intermetallic compounds -- Metallography -- Periodicals; Metallic glasses -- Periodicals; Composés intermétalliques -- Métallographie -- Périodiques; 669.94
• DOI: 10.1016/j.intermet.2019.106586
• Languages: English
• ISSNs: 0966-9795

Abstract

Abstract: Fe/Mo bulk diffusion couples are annealed at 1050–1200 °C to study the growth and diffusion behaviour of μ phase in the Fe–Mo system. Parabolic growth constants and integrated interdiffusion coefficients are determined in the μ phase. The activation energies for the growth of μ phase and for the integrated interdiffusion coefficients are estimated as 228 ± 22 and 733 ± 10 kJ/mol, respectively. The relatively high activation energy for interdiffusion in μ phase, determined at high homologous temperature of 0.8–0.9, indicates that μ phase grows by lattice diffusion. Phase boundary compositions, measured by EPMA, indicates the homogeneity range of μ phase to be ~ 3 at.% higher towards the Fe–rich side (i.e., 36 at.% Mo) as compared to the reported composition of 39–44 at.% Mo in the phase diagram. Highlights: Interdiffusion study is conducted in the Fe–Mo system. The phase boundary compositions are measured by EPMA. Parabolic growth constants and diffusion parameters are determined in the μ phase. Our analysis indicates that diffusion process should be discussed based on diffusion parameters.