Solid-gas reactions driven by mechanical alloying of niobium and tantalum in nitrogen

Journal Article · Thu Apr 01 00:00:00 EST 1999 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-999-0161-2· OSTI ID:347489

Liu, L ^[1]; Lu, L ^[2]; Chen, L; Qin, Y; Zhang, L D ^[3]

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1. Huazhong Univ. of Science and Technology, Wuhan (China). Dept. of Materials Science and Engineering
2. National Univ. of Singapore (Singapore). Dept. of Production and Engineering
3. Academia Sinica, Hefei (China). Inst. of Solid State Physics

Solid-gas reactions of niobium and tantalum with molecular nitrogen driven by mechanical alloying (MA) have been investigated by X-ray diffraction, transmission electron microscopy, and differential thermal analysis. It was found that the phase transition followed a sequence of Nb{sub 2}N {r_arrow} Nb{sub 3}N{sub 4} {r_arrow} NbN when Nb was milled with N{sub 2}. The chemosorption of nitrogen onto the clean metal surfaces created by ball milling is believed to be the fundamental process governing solid-gas reactions, and the defects generated during MA can promote the diffusion of adsorbed nitrogen, and consequently the formation of metal nitrides. The difference in phase transition between the two systems is discussed.

• Sponsoring Organization: USDOE
• OSTI ID: 347489
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Vol. 30, Issue 4; Other Information: PBD: Apr 1999
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
PHASE STUDIES
SYNTHESIS
NIOBIUM NITRIDES
TANTALUM NITRIDES
MILLING
NITROGEN
X-RAY DIFFRACTION
MICROSCOPY
DIFFERENTIAL THERMAL ANALYSIS