On the Relief of the Residual Stresses in Ceramic-Metal Joints by a Layered Braze Structure

Matteo Galli 1,2John Botsis 1Jolanta Janczak-Rusch 2

1. Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne 1015, Switzerland
2. Empa, Materials Technology and Research (Empa), Überlandstrasse 129, Dübendorf 8600, Switzerland


The potential of active brazing filler metal modification by ceramic particle addition, with the aim of to reduce the cooling induced stresses and enhance the strength of ceramic metal joints, is studied. The addition of ceramic particles allows tailoring the mechanical properties of the filler metal and improving its mechanical behaviour at higher temperature, however simple reinforcing of the interlayer has a detrimental effect at lower temperature because, due to the filler strengthening, residual stress relief via plasticity is limited. Thus a layered joint structure is proposed: reinforced and not reinforced layers of different thicknesses and compositions are combined in an optimal manner to minimize residual stress.
Reinforced active filler alloys are produced by adding SiC particles to Ag-Cu-In-Ti alloy Incusil-ABA up to 30% vol. and used in combination with the pure filler alloy for joining Si3N4-TiN ceramics to 14NiCr14 steel. The joints produced are tested in 4-point bending. Bending strengths of joints with different layouts (thickness and composition of layers) are compared with experimental data obtained for the same material systems brazed with single unreinforced filler metals.
The evaluation of residual stresses and the optimization of the joint layout are carried out by FE modelling; temperature dependent mechanical properties are assumed for all the constituents, the elasto-plastic properties of the reinforced filler metals are obtained by homogenization.
Both experimental and numerical results indicate as an optimal solution a “sandwich” layout with a central reinforced layer between two unreinforced layers in contact with the base materials; experimental data show that the average bending strength of such joints is 20% higher than that of joints brazed with a single layer of unreinforced filler metal.

Legal notice
  • Legal notice:

    Copyright (c) Pielaszek Research, all rights reserved.
    The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
    In every case, proper references including Author(s) name(s) and URL of this webpage: http://science24.com/paper/3613 must be provided.


Related papers
  1. Experimental evaluation of melting point depression in AlSi/AlN nanomultilayer system
  2. How to join heat sensitive materials?
  3. The Wetting Behaviour and Interface Structure of Unreinforced and Particle Reinforced Lead-Free Solders
  4. Optimization of particle reinforced lead-free solders
  5. Microstructural evaluation during particles addition to lead-free solders
  6. Evaluation of fibre-cement interfacial properties by SEM-based push-out tests
  7. Fractography as a tool to optimize joint design and the brazing process
  8. Development of nanoparticle reinforced brazing filler metals and solders: the aspects of downscaling from micro to nanoscale
  9. Description of the mechanical performance of Cu-SnAgCu-Cu joints
  10. Size and constraining effects in lead-free solder joints
  11. Comparison of three different active filler metals used for brazing ceramic-to-ceramic and ceramic-to-metal joints
  12. Model for intermetallic phase and intermetallic compound solidification during diffusion soldering
  13. Transition from solidification to the first solid/solid transformation during diffusion soldering

Presentation: oral at E-MRS Fall Meeting 2005, Symposium H, by Matteo Galli
See On-line Journal of E-MRS Fall Meeting 2005

Submitted: 2005-05-19 12:51
Revised:   2009-06-07 00:44
Web science24.com
© 1998-2022 pielaszek research, all rights reserved Powered by the Conference Engine