Author Topic: thermal compound as anti sieze?  (Read 5789 times)

0 Members and 1 Guest are viewing this topic.

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
thermal compound as anti sieze?
« on: July 09, 2023, 02:48:29 am »
I have stainless fasteners going into aluminum in a welding fixture. I was thinking to use MX4 as anti sieze, to break up the discontinuities in the thermal path due to the bolts and also to prevent it from locking up.

Think it will work? or is this a bad idea?
 

Offline KE5FX

  • Super Contributor
  • ***
  • Posts: 1890
  • Country: us
    • KE5FX.COM
Re: thermal compound as anti sieze?
« Reply #1 on: July 09, 2023, 03:17:36 am »
GPT4 actually yields a fairly decent answer:

Quote
It might not be the best choice for your application. For a few reasons:

    Thermal properties: MX-4 is designed to maximize thermal conductivity for electronics, but in an application where much higher heat is involved, like in a welding fixture, it might not perform as well.

    Durability under stress: A welding environment may subject the compound to extreme heat and potential mechanical stress that MX-4 is not designed to withstand.

    Galvanic corrosion: When using stainless steel fasteners in aluminum, there's a potential issue with galvanic corrosion. MX-4 does not have any properties to prevent this type of corrosion.

Instead, you might want to consider a specific anti-seize compound designed for high-temperature environments and to prevent galvanic corrosion. Anti-seize compounds that contain copper, nickel, or aluminum particles in a high-heat-resistant lubricant can provide the protection you need. They fill the microscopic voids just like the MX-4, but are also designed to prevent seizing, galling, and corrosion in high-heat and high-pressure environments like that of your welding fixture. As always, ensure the selected product is suitable for your specific temperature range and environmental conditions.
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #2 on: July 09, 2023, 03:44:22 am »
Where does that thing get its basis from?

Maybe I should be more specific:
contents
1) silicone oil
2) aluminum powder
3) silver oxide

What base does a real anti seize use then?

whats it missing or what should it have instead?
« Last Edit: July 09, 2023, 03:48:53 am by coppercone2 »
 

Offline beanflying

  • Super Contributor
  • ***
  • Posts: 7360
  • Country: au
  • Toys so very many Toys.
Re: thermal compound as anti sieze?
« Reply #3 on: July 09, 2023, 04:27:29 am »
Lookup Galling and some steps to minimise it Helicoils or using Nutserts are good options too. https://www.metalsupermarkets.com/what-is-galling/#:~:text=Applications%20with%20ductile%20metals%20placed,undergo%20as%20they%20are%20torqued.

Just buy a quality anti seize if you are worried one good option is Loctite LB 8009 but most heavy duty industrial products will work fine just look at their datasheets for Aluminium and Stainless use if in doubt.

Good reasons NOT to use thermal compound is they set up rockhard when exposed to even lower heats before you get to them not being very good at what you propose using it for.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #4 on: July 09, 2023, 04:52:57 am »
I assume the problem is that the silicone oil can evaporate. Does it mean that the vapor pressure and boiling point is too low?

What solutions are there to this problem. How do you devoltalize oil?

It sounds like there is a pretty specific crux here.
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #5 on: July 09, 2023, 04:56:19 am »
you know what i will do a experiment with a deep hole, bolt and a acetylene torch. I will roast a few samples to see how it behaves when totally over heated. I think the only technicality is if its a through hole or just a hole. I think I have a few pieces of stock laying around.
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #6 on: July 09, 2023, 05:01:20 am »
and for low temperature applications I wonder if a gasket would keep the grease in tact to prevent the liquid part from evaporating if that is the case. I don't think the silicone oil can react with the inorganic materials or polymerize. Maybe.

But I see the old HP transistors still have silicone oil under them and its like 60+ years old. 

is the key to anti sieze the heavy naphthalene oil compounds?
« Last Edit: July 09, 2023, 05:17:58 am by coppercone2 »
 

Offline Gyro

  • Super Contributor
  • ***
  • Posts: 9501
  • Country: gb
Re: thermal compound as anti sieze?
« Reply #7 on: July 09, 2023, 09:34:05 am »
Why not just ordinary (Copper) anti sieze compound? It's hight temperature tolerant and works fine for things like steel bolts going into Aluminium alloy brake calipers in exposed conditions.
Best Regards, Chris
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #8 on: July 09, 2023, 05:46:55 pm »
I kinda wanted to know if anyone knew what the magic ingredient is because they look largely the same. I think its a higher melting point oil.
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28368
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: thermal compound as anti sieze?
« Reply #9 on: July 10, 2023, 08:55:15 am »
Why not just ordinary (Copper) anti sieze compound? It's hight temperature tolerant and works fine for things like steel bolts going into Aluminium alloy brake calipers in exposed conditions.
Mixing copper and alloy is not a good idea ever.

Went away from copper based antiseize of any brand after discovering copper compounds can compromise high tensile steels.
Use only nickel based antiseize now, Loctite 76754
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 

Online T3sl4co1l

  • Super Contributor
  • ***
  • Posts: 21675
  • Country: us
  • Expert, Analog Electronics, PCB Layout, EMC
    • Seven Transistor Labs
Re: thermal compound as anti sieze?
« Reply #10 on: July 10, 2023, 12:22:21 pm »
No. It is abrasive, not lubricating.

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #11 on: July 11, 2023, 07:13:08 am »
alright I got nickel anti seize

I figure it will be pretty damn dry if its used for welding but I don't need alot
 

Offline thm_w

  • Super Contributor
  • ***
  • Posts: 6364
  • Country: ca
  • Non-expert
Re: thermal compound as anti sieze?
« Reply #12 on: July 13, 2023, 09:49:14 pm »
MX4 just seems expensive compared to cheap anti-seize (copper or mixed), if its used often.

Why not just ordinary (Copper) anti sieze compound? It's hight temperature tolerant and works fine for things like steel bolts going into Aluminium alloy brake calipers in exposed conditions.
Mixing copper and alloy is not a good idea ever.

Went away from copper based antiseize of any brand after discovering copper compounds can compromise high tensile steels.
Use only nickel based antiseize now, Loctite 76754

Citation?

76764 is graphite based, 77164 is nickel/aluminum based, don't know what 76754 is, can't find the number.

Quote
Copper vs. Nickel Anti Seize

When it comes to choosing between copper or nickel anti-seize lubricants, there are several factors that you’ll want to keep in mind. Generally speaking, copper anti-seize is designed specifically for use on metallic threads, while nickel anti-seize is recommended for all types of threaded fasteners, including aluminum threads as well as stainless steel. Copper anti-seize is typically more expensive than nickel; however, it provides superior protection against corrosion due to its higher solids content (up to 40%). On the other hand, nickel anti-seize operates at higher temperatures (up to 2200°F) compared to copper, which makes it ideal for high-performance applications such as automotive engines and aerospace components where temperatures may reach 2000°F or more.

Additionally, nickel anti-seize has an overall lower coefficient of friction which helps reduce wear over time.

Finally, when deciding between the two types of lubricant, consider your environment, as this can play a role in the type of product you choose. The copper-based lubricant has excellent water resistance but tends to be less stable than nickel-based lubricants in acidic environments such as salt spray, which makes it better suited for dryer climates. Nickel-based lubricants offer better oxidation stability but do not fare well in moist environments due to their lower water resistance capabilities.
« Last Edit: July 13, 2023, 09:55:23 pm by thm_w »
Profile -> Modify profile -> Look and Layout ->  Don't show users' signatures
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28368
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: thermal compound as anti sieze?
« Reply #13 on: July 14, 2023, 11:33:48 am »
MX4 just seems expensive compared to cheap anti-seize (copper or mixed), if its used often.

Why not just ordinary (Copper) anti sieze compound? It's hight temperature tolerant and works fine for things like steel bolts going into Aluminium alloy brake calipers in exposed conditions.
Mixing copper and alloy is not a good idea ever.

Went away from copper based antiseize of any brand after discovering copper compounds can compromise high tensile steels.
Use only nickel based antiseize now, Loctite 76754

Citation?

76764 is graphite based, 77164 is nickel/aluminum based, don't know what 76754 is, can't find the number.
Sorry can't find it, looked and looked.
AFAIK it was based on hydrogen embrittlement of HT fasteners from Molybdenum disulfide usage.
However none of the antiseize datasheets show that as being used these days.....maybe formulations have changed.  :-//
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 
The following users thanked this post: thm_w

Online coppercone2Topic starter

  • Super Contributor
  • ***
  • Posts: 9446
  • Country: us
  • $
Re: thermal compound as anti sieze?
« Reply #14 on: July 15, 2023, 11:05:18 pm »
sulfide does something to the metal to make it absorb hydrogen which is generated by corrosion from what I understand
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 28368
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: thermal compound as anti sieze?
« Reply #15 on: July 16, 2023, 05:08:43 am »
sulfide does something to the metal to make it absorb hydrogen which is generated by corrosion from what I understand
Yep, it's a type of Stress corrosion cracking (SCC)
https://en.wikipedia.org/wiki/Stress_corrosion_cracking
Avid Rabid Hobbyist
Siglent Youtube channel: https://www.youtube.com/@SiglentVideo/videos
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf