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Title: DEVELOPMENT OF A HIGH-TEMPERATURE CERAMIC BRAZE: ANALYSIS OF PHASE EQUILIBRIA IN THE Pd-Ag-CuOx SYSTEM

Abstract

This paper describes the effects of small palladium additions on the phase equilibria in the Ag-CuOx system. Below a concentration of 5 mol%, palladium was found to increase the temperature of the eutectic reaction present in the pseudobinary system, but have little effect on a higher temperature monotectic reaction. However once enough palladium was added to increase the pseudoternary solidus temperature to that of the lower boundary for this three-phase field (~970°C), the lower boundary begins to increase in temperature as well. The addition of palladium also causes the original eutectic point to move to lower silver concentrations, which also causes a convergence of the two new three-phase fields, CuOx + L1 + L2 and CuOx + α + L1. This suggests that with higher palladium concentrations, a peritectic reaction, α + L1 + L2 → CuOx, may eventually be observed in the system.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1240238
Report Number(s):
PNNL-SA-48107
AA6010000
DOE Contract Number:
AC05-76RL01830
Resource Type:
Conference
Resource Relation:
Conference: Mechanical Properties and Performance of Engineering Ceramics II: 30th International Conference on Advanced Ceramics and Composites, January 22-27, 2006, Cocoa Beach, Florida. Ceramic Engineering and Science Proceedings, 27(2):483-490
Country of Publication:
United States
Language:
English
Subject:
air brazing; high temperature

Citation Formats

Weil, K. Scott, and Darsell, Jens T.. DEVELOPMENT OF A HIGH-TEMPERATURE CERAMIC BRAZE: ANALYSIS OF PHASE EQUILIBRIA IN THE Pd-Ag-CuOx SYSTEM. United States: N. p., 2006. Web. doi:10.1002/9780470291313.ch46.
Weil, K. Scott, & Darsell, Jens T.. DEVELOPMENT OF A HIGH-TEMPERATURE CERAMIC BRAZE: ANALYSIS OF PHASE EQUILIBRIA IN THE Pd-Ag-CuOx SYSTEM. United States. doi:10.1002/9780470291313.ch46.
Weil, K. Scott, and Darsell, Jens T.. Wed . "DEVELOPMENT OF A HIGH-TEMPERATURE CERAMIC BRAZE: ANALYSIS OF PHASE EQUILIBRIA IN THE Pd-Ag-CuOx SYSTEM". United States. doi:10.1002/9780470291313.ch46.
@article{osti_1240238,
title = {DEVELOPMENT OF A HIGH-TEMPERATURE CERAMIC BRAZE: ANALYSIS OF PHASE EQUILIBRIA IN THE Pd-Ag-CuOx SYSTEM},
author = {Weil, K. Scott and Darsell, Jens T.},
abstractNote = {This paper describes the effects of small palladium additions on the phase equilibria in the Ag-CuOx system. Below a concentration of 5 mol%, palladium was found to increase the temperature of the eutectic reaction present in the pseudobinary system, but have little effect on a higher temperature monotectic reaction. However once enough palladium was added to increase the pseudoternary solidus temperature to that of the lower boundary for this three-phase field (~970°C), the lower boundary begins to increase in temperature as well. The addition of palladium also causes the original eutectic point to move to lower silver concentrations, which also causes a convergence of the two new three-phase fields, CuOx + L1 + L2 and CuOx + α + L1. This suggests that with higher palladium concentrations, a peritectic reaction, α + L1 + L2 → CuOx, may eventually be observed in the system.},
doi = {10.1002/9780470291313.ch46},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 18 00:00:00 EST 2006},
month = {Wed Jan 18 00:00:00 EST 2006}
}

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