Diffusion bonding of dissimilar ceramics
AssigneeInternational Business Machines Corporation
InventorsWilliam W. Chow, Eugene B. Rigby
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Abstract
Diffusion bonding of dissimilar ceramics can be accomplished by the application of pressure only while the ceramics are at a temperature at which their expansion rates are the same. A process for manufacturing magnetic head cores is disclosed where a magnetic ferrite is diffusion bonded to a non-magnetic ceramic by heating the core pieces to the expansion rate crossover temperature and then applying the diffusion bonding pressure. The pressure is removed either before or after the bonded pieces are cooled.
Claims12
A process for diffusion bonding of ceramic pieces respectively consisting of dissimilar ceramic materials having expansion curves with a certain temperature range where the respective thermal expansion curves of each ceramic material intersect, said process comprising the steps of:
- obtaining the ceramic pieces;
- placing the obtained ceramic pieces adjacent each other for bonding;
- heating the placed ceramic pieces to the certain temperature range;
- applying pressure to the heated ceramic pieces to effect a diffusion bond while maintaining the ceramic pieces at the certain temperature range;
- removing the applied pressure;
- and
- cooling the bonded ceramic pieces to ambient temperature.
A process for making parts of a head core for a magnetic head by the diffusion bonding of a formed magnetic ceramic block to a formed non-magnetic ceramic block with the dissimilar ceramic materials having expansion curves with a certain temperature range where the respective thermal expansion curves of each ceramic material intersect, said process comprising the steps of:
- obtaining the formed magnetic ceramic block;
- obtaining the formed non-magnetic ceramic block;
- placing the obtained ceramic blocks adjacent each other in the bonding configuration;
- heating the placed ceramic blocks to the certain temperature range;
- applying pressure for a time period to the heated ceramic blocks to effect a diffusion bond while maintaining the ceramic pieces at the certain temperature range;
- and
- removing the applied pressure while cooling the bonded ceramic pieces to ambient temperature.
Dependencies are inferred from the claim text.