Ivan,

If you have to use nichrome, silicone sheets are a not-too-dreadful solution if you can clamp the wires to the plate.

But.

If you have any choice in the matter, I strongly recommend metal foil kapton heaters.

https://www.robotdigg.com/product/876/12-or-24v-100w-100,-120-or-150mm-kapton-film-heater?gclid=Cj0KCQjwh7zWBRCiARIsAId9b4qXphYczSHlGQy_DhLz5uh5FsLQ94kSQTdGCKoLtrUt3oZN-Ys-HosaAjU_EALw_wcB

They can be made to any planar shape, and almost any resistance.

I've used them in vacuo, and over temperatures from --160 to +100 degC

James's choice is good. A cheap alternative if you specifically want to use nichrome and get a good temporary bond is that silicone paste used to attach transistors to heatsinks. However in both cases you must recalculate for the reduced heat transfer coefficient of the electrical insulator.

For higher temperatures (400C+) there are a range of fireclays which are electrical insulators, again you must calculate and allow for the Tc.

https://www.researchgate.net/deref/https%3A%2F%2Fwww.robotdigg.com%2Fproduct%2F876%2F12-or-24v-100w-100%2C-120-or-150mm-kapton-film-heater%3Fgclid%3DCj0KCQjwh7zWBRCiARIsAId9b4qXphYczSHlGQy_DhLz5uh5FsLQ94kSQTdGCKoLtrUt3oZN-Ys-HosaAjU_EALw_wcB

Mohsen,

Do you have anything to add beyond simply copying what I wrote?

Ivan,

I've used Auxiplast to fabricate custom Kapton-backed foils - may I ask what temperature range you're working at?

Good day, I also have the same challenge. I want to use nicotine wire to heat up a reactor and attain temperatures of about 600. There are lacks of materials around me. What is the best and cheapest method to use. I read about the silicon sheets and fire bricks. Are there other options