The Secret of Componant 9Rom circle-m

[DarkspARCS]

lol... almost sounds like a movie title! :lol:

Here's a componant I've discovered in my electronics quests that has an interesting yield:



Appears to be a familiar looking palladium/ silver alloy sometimes found in circuit breakers... ya think? 8)

Nice rainbow weathering pattern on alloy gives this thing away. Thought I'd share my find, look for these lil black boxes on your boards...

 

[Militoy]

You didn't mention the make or model of the breaker you've displayed - Heinemann; Airpax; Eaton or - is 9Rom circle-m the marking on the breaker? Any other markings? Detail photos of the trademark? :?:

 

[copperkid_18]

from what I have seen those are ceramic, plated with some type of metal.

 

[Findm-Keepm]

What you have is a Posistor, probably PTHM9 series, made by Murata. That's their marking - the C with the M. They specify the material as BaTio3:

http://www.murata.com/products/thermistor/basic/thermistor/index.html

A similar device (thermistor) is used in TV degaussing circuits. I've never known them to have any PMs either.

Cheers,

 

[johnny309]

TV degaussing circuits and other termistors are using the same configuration of titanium oxides.I don't think they would mean anything even to a large e-scrape refiner.....for the small amount in electronic devices and other contaminates(lead,tin,sulphur).

 

[DarkspARCS]

so... even if the round button is a titanium oxide - shouldn't the connectors be plated with pm? perhaps the contacts - some of which I've seen weathered with that familiar black tinge related to silver and paladium - are plated with palladium and that's what's giving the button surface it's rainbow weathered sheen?

 

[NoIdea]

Thanks for the heads up on these, i have a jar filled with these little buttons. Tried nitric on a few of these a few years ago, not much of a reaction if any, so palladium could be the go.

Go on, someone here surely whats to see what the conductive/connecting coating is? :mrgreen:

Cheers

Deano

 

[Geo]

circuit breakers will almost always have silver/tungsten points. that may be the reason they didnt react to nitric very easily. it takes heat and time to dissolve the silver from the tungsten sponge.

 

[eesakiwi]

I have seen those discs in CRT TV's & modern fridge compressors.
They are inside the black plastic box that plugs into the side of the compressor.

Common as, I think they are ceramic.
-----------
Since then I have had a look around the net & wrote a bunch of stuff up & the net crashed so I'm typoing it up again.

I have seen these round discs in modern fridge compressor starters & CRT TV's.
They apperar ceramic.

I have found they are actually a PTC (positive temperature coefficient)

About the fridge starters.
http://www.sensata.com/download/8ea.pdf

About the chemical thats in it.
http://en.wikipedia.org/wiki/Barium_titanate

1Kg of it is worth US$112
http://www.advancedmaterials.us/5622-ON4.htm

I'm quite happy about this post, after years of wondering what that thing is I have now found out.
It took a bit to search for info, no wonder no one else knew what it was.
Even though all the infos there on the net, there was no connection between the 3 main subjects. Damn google.

 

[DarkspARCS]

Thank you for such exhaustive research into this eesakiwi!

that last link provided some additional uses for this compound, that I found interesting:

barium titanate (BaTiO3) has found widespread applications in multi-layer ceramic capacitors

while I must admit that the price per kg is mediocre at best I suppose if some one found a buyer of this stuff it wouldn't hurt to crack it open and toss it into the BaTiO3 bin... lmao. however, I'm curious now on how carcinogenic this barium/ titanium alloy is compared to barium alone... (gulp).

could mean that even the MCCs we're pulling off the PCBs causes cancer too!

-edit too add-

Found an msds for it:

Barium-Titanate MSDS pdf

seems safe enough... but can cause baritosis via skin absorption and/ or inhalation of BaTiO3 dust...