Thermal Grease

[Garey Barrell]

John -

Yes, I'm sure it's been long discontinued.   I sure thought I recalled
being cautioned about it when we used it in the early 60's.  We used it
on telemetry transmitters on Redstone and Saturn.  Funny the things you
remember, especially when you're not sure what you had for lunch
yesterday!  :-)

Garey

J. Forster wrote:

>It is possible that at one time BeO was used in grease, but I've never seen it and
>I've been using the stuff since 1963. I very much doubt it's in commercial use
>anymore. In the late 60s, I was using BeO washers on TO-3 transistors.
>
>FWIW,
>-John
>
>
>Garey Barrell wrote:
>
>
>
>>Wes -
>>
>>That makes me feel better.   I thought I remembered beryllium oxide
>>grease.  NASA certainly was well above us "mere mortals!"   At least in
>>the 60's when I was there...
>>
>>Garey - K4OAH
>>
>>W. Kranitz wrote:
>>
>>
>>
>>>The "new" style white silicon grease is called "Type Z9"
>>>Silicon Heat Sink Compound. Some special application versions
>>>of this compound used beryllium oxide, but these were not available
>>>to us mear mortals. Most common versions use aluminum or zinc
>>>compounds. Some of the newer types use Micronized Silver (eg, DYNEX
>>>Silver Thermal Compound). These are used for the high heat transfer
>>>needed for modern microprocessors.
>>>
>>>
>>>Garey Barrell wrote:
>>>
>>>
>>>
>>>>Jerry -
>>>>
>>>>There are at least two types that I am aware of.
>>>>
>>>>The "old" style was clear silicone grease.
>>>>
>>>>The "new" style is white silicone grease loaded with beryllium oxide.
>>>>
>>>>Both work pretty much the same, the purpose being to fill any  TINY  air
>>>>pockets trapped between what ideally would be two "perfectly" flat
>>>>surfaces.  The idea is that the grease is a better at heat transfer than
>>>>air.  It is NOT a better conductor than metal, so a big blob of grease
>>>>isn't going to transfer much heat between two surfaces that don't
>>>>touch.!
>>>>
>>>>Proper use calls for only a VERY thin smear.  Most people use WAY too
>>>>much, which of course gets squeezed out when the two pieces are clamped
>>>>together.
>>>>
>>>>By the way, beryllium oxide DUST is considered very toxic if inhaled, so
>>>>I guess you wouldn't want to eat the stuff!
>>>>
>>>>73, Garey - K4OAH
>>>>Atlanta
>>>>
>>>>
>
>
>
>
>
>

-----------------------------------------------------------
This list is a public service of the City of Tempe, Arizona
-----------------------------------------------------------

Subscription control - http://www.tempe.gov/lists/control.asp?list=BOATANCHORS
To post - BOATANCHORS at LISTSERV.TEMPE.GOV
Archives - http://interactive.tempe.gov/archives/BOATANCHORS.html