Using a conductive graphite felt as a microwave absorption material in a microwave kiln would not work the same way as heating food in a microwave oven. Microwave kilns are specifically designed for high-temperature applications such as glass fusing or ceramics.
In a microwave oven, the microwaves primarily interact with water, fat, and sugar molecules in the food, causing them to vibrate and generate heat. However, a conductive graphite felt does not contain these molecules in significant quantities. While graphite is a conductor of electricity, it is not a good absorber of microwaves in the same way that water, fat, or sugar are.
Microwave kilns, on the other hand, work on a different principle. They use microwaves to heat the material being worked on, such as glass or ceramics, indirectly through thermal conduction. The microwaves heat the graphite felt, which, in turn, transfers the heat to the material being processed. This process relies on the high temperatures achieved by the graphite felt to transfer heat to the surrounding material rather than direct microwave absorption.
So, while a conductive graphite felt can be used in a microwave kiln to facilitate heating of glass or ceramics, it would not work in the same way as heating food in a microwave oven. The principles and mechanisms involved in these two applications are different.