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Towards an Understanding of the Reaction Sequences in Brazed Joints: Investigation of the Ti-Cu-O Ternary at 945°C.

Published online by Cambridge University Press:  15 February 2011

G. P. Kelkar ,
A. H. Carim  and
K. E. Spear
G. P. Kelkar
Affiliation:
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802.
A. H. Carim
Affiliation:
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802.
K. E. Spear
Affiliation:
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802.
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Abstract

The joining of ceramics using active metal braze alloys is an attractive technique and has been used for a variety of material systems. The braze alloys usually contain an active element such as Ti which can reduce the ceramic and form a strong bond across the interface. Microstructural characterizations of brazed interfaces have been widely reported, though reasons for the formation of reaction products and their sequence is not clear due to the lack of thermodynamic information on the phases formed.

The Ag-Cu-Ti/Al2O3 system contains an interface where Ti, the active element in the braze alloy, reduces Al2O3 to form layers of reaction products which include (Ti,Cu,Al)6O, an M6X type compound. In this study we have looked at the Ti-Cu-O system as a first step towards understanding the Ag-Cu-Ti/Al2O3 system. A section of the Ti-Cu-O ternary was investigated at 945°C. The system contains two M6X type compounds, Ti4Cu2O and Ti3Cu3O, which have independent single phase fields. A Ti activity diagram was generated from the available thermodynamic information and the knowledge of the ternary section. The two reaction sequences reported for such interfaces were analyzed based on the activity diagram.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 314: Symposium R – Joining and Adhesion of Advanced Inorganic Materials , 1993 , 71
Copyright
Copyright © Materials Research Society 1993

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References

1. Loehman, R. E. and Tomsia, A. P. ,”Joining of Ceramics,” Ceramic Bulletin, 67[2], pp. 375–380, 1988.Google Scholar
2.. Kingery, W. D., “Metal-Ceramic Interactions : I, Factors Affecting Fabrication and Properties of Cermet Bodies,” J. Am. Ceram. Soc., 36[11], pp. 362–365, 1953.Google Scholar
3. Okamoto, T., “Interfacial structure of metal-ceramic joints,” ISIJ International, 30[12], pp. 1033–1040, 1990.Google Scholar
4.. Mizuhara, H. and Heubel, E., “Joining of Ceramic to Metal with Ductile Active Filler Metal,” Welding J., 65[10], pp. 43–51, 1986.Google Scholar
5. Moorhead, A. J. and Keating, H., “Direct Brazing of Ceramics for Advanced Heavy-Duty Diesels,” Welding J., 65[10], pp. 17–31, 1986.Google Scholar
6. Santella, M. L., Horton, J. A., and Pak, J. J., “Microstructure of Alumina Brazed with a Silver-Copper-Titanium Alloy,” J. Am. Ceram. Soc., 73 (6), pp. 1785–87, 1990.Google Scholar
7. Barbier, F., Peytour, C., and Revcolevschi, A., “Microstructural Study of the Brazed Joint between Alumina and Ti-6A1–4V Alloy,” J. Am. Ceram. Soc. 73 (6), pp. 1582–86, 1990.Google Scholar
8. Carim, A. H., “Convergent-Beam Electron Diffraction ‘Fingerprinting’ of M6X Phases at Brazed Ceramic Joints,” Scripta Metall. et Mater. 25, pp. 51–54 (1991).Google Scholar
9. Kelkar, G. P. and Carim, A. H., “Synthesis, properties, and ternary phase stability of M6X compounds in the Ti-Cu-O system,” J. Am. Ceram. Soc. 76 (6), in press (1993).Google Scholar
10. Kubaschewski, O. and Dench, W. A., “The free-energy diagram of the system titaniumoxygen,” J. Inst. Met., Vol.82, pp.87–91, 1953–1954.Google Scholar
11. Komarek, K. L. and Silver, M., “Thermodynamic Properties of Zirconium-Oxygen, Titanium-Oxygen and Hafnium-Oxygen Alloys,” Thermodynamics of Nuclear Materials, Proc. of Symp. on Thermodynamics of Nuclear Materials, I. A. E. A., Vienna, 21–25, May 1962.Google Scholar
12. Murray, J. L. and Wreidt, H. A.,”The O-Ti (Oxygen-Titanium) System,” Phase Diagrams of Binary Titanium Alloys, Editor Murray, J. L., ASM, Metals Park, OH, 1987.Google Scholar
13. JANAF Thermochemical Tables, J. of Phys. and Chem. Reference Data, Vol 14, 1985.Google Scholar
14. Thermochemistry of ceramic-metal reactions in Ti-Si-N and Ti-Si-C systems at high temperatures and pressures, Sambasivan, S., Ph.D. Thesis, Arizona State University, December 1990.Google Scholar
15. van Loo, F. J. J., “Multiphase Diffusion in Binary and Ternary Solid-State Systems,” Prog. Solid St. Chem., Vol.20, pp. 47–99, 1990.Google Scholar