Microwave sintering process improvements
Discharge is often encountered when sintering in a multimode
cavity. The effect of the discharge phenomenon on
temperature measurement when using a thermocouple is illustrated
in Fig. 1, which shows that the discharge causes
the thermocouple readout to fluctuate. When discharge is
severe, it causes damage to the sintering packet and thermocouple.
In order to overcome this problem the following
steps must be taken:
1. Optimize the mass of the sample [7].
2. Expose the sample directly to the microwave field (no
crucible).
3. Carefully align the sintering packet (and sample)
along the vertical axis of the microwave cavity.
4. Ground the thermocouple.
5. Optimize the heating rate