The formation of nitride phases during diffusion bonding of Ni-Cr alloys with Si{sub 3}N{sub 4}-ceramic

Journal Article · Tue Aug 01 04:00:00 EDT 1995 · High Temperature and Materials Science

OSTI ID:218640

Kodentsov, A A; Loo, F J.J. van ^[1]; Kivilahti, J K ^[2]

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1. Eindhoven Univ. of Technology (Netherlands). Lab. of Solid State Chemistry and Materials Science
2. Helsinki Univ. of Technology, Espoo (Finland). Dept. of Materials Science and Engineering

Interaction between dense silicon nitride ceramics and Ni and/or Ni-Cr alloys during diffusion bonding at 1,398 K was investigated. The reaction phenomena in these systems can be explained by assuming a high nitrogen pressure (fugacity), which is built up at the contact surface. Experimental results on diffusion couples were compared with those of direct nitriding of Ni-Cr(Si) alloys from the gas atmosphere (1--6,000 bar). Based on experimental data and thermodynamic considerations of the Ni-Cr-Si-N system, evidence for ``up hill`` diffusion of nitrogen near the precipitation front in the reaction zone between dense Si{sub 3}N{sub 4} and Ni-Cr alloys with 10--18 at% of Cr was found. This can be attributed to the relative instability of cubic chromium nitride (CrN) and the strong Cr-N interaction in the nickel-based solid solution.

• OSTI ID: 218640
• Report Number(s): CONF-940468--
• Journal Information: High Temperature and Materials Science, Journal Name: High Temperature and Materials Science Journal Issue: 1-3 Vol. 34; ISSN 1080-1278; ISSN HTMSFP
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BONDING
CHROMIUM ALLOYS
CHROMIUM NITRIDES
COMPOSITE MATERIALS
NICKEL ALLOYS
NICKEL NITRIDES
NITRIDATION
PHASE STUDIES
SILICON NITRIDES