where to get ceramic caulk?

[Lynx_Arc]

I need something to glue a soldering iron heating element back together the white adhesive finally crumbled into dust and it is loose.
anyone know where to get some high temp adhesive the can glue copper to ceramic.

 

[mudman cj]

Aremco Ceramabond 571 might work for you. Among similar products that I am aware of, it has the closest expansion match to that of copper.

 

[Lynx_Arc]

guess I will have to call the electronic supply place. It is an old ungar 50 watt heating element which I like most soldering irons with such a big output have huge tips and are heavy this is not that big and heats up fast good for most stuff I do. I have some artic alumina I wonder if that would do the trick.

 

[mudman cj]

Arctic alumina epoxy might work depending upon its thermal expansion coefficient. Unfortunately, they don't make that data available, so you will just have to try it and see. If its too low then it will be full of cracks and *should* come out easily (but don't hold me to that ;)).

 

[The Dane]

Gun Gum exhaust repair?

 

[Lynx_Arc]

Arctic alumina epoxy might work depending upon its thermal expansion coefficient. Unfortunately, they don't make that data available, so you will just have to try it and see. If its too low then it will be full of cracks and *should* come out easily (but don't hold me to that ;)).

that was what I was thinking, if it dries hard then it may crack when the the copper and ceramic both expand due to heat and contract at different rates when cooling.

 

[Lynx_Arc]

Gun Gum exhaust repair?

not sure exhaust repair stuff is high enough temp rated or not unless it is for repairing headers.

 

[mudman cj]

I believe the ceramic component of arctic alumina adhesive is alumina, not only because of the name :rolleyes:, but because alumina (aluminum oxide) has a fairly high thermal conductivity for a ceramic material and it makes sense to use it in this application.

The thermal expansion coefficient of alumina is about 7-8*10^-6/C compared to about 19*10-6/C for copper. So, the copper expands at over twice the rate of alumina. The only saving grace is that the usage temperature is limited to about 750F (399C). But even that will generate considerable stresses. After further thought I have to give this approach a low likelihood of success, but I hope I am wrong.

 

[Lynx_Arc]

well there was a white material holding it together that has turned into powder over the last 30 years of use. I may just try the arctic alumina adhesive the worst it could do is probably just turn into dust after awhile too I would guess