Memorandum on Solid Lubricants

James & Son

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Memorandum on Solid Lubricants
This is an interesting read as the issues in this article pretty much parallel the issues for the science on the subject today up to 2014. See why below.

Read it here
http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1920.tb06502.x/pdf

or read it here, which includes the credits and 1920 publish date
https://archive.org/stream/memorandumonsoli00grearich/memorandumonsoli00grearich_djvu.txt

The issue back then was to use the nano colloidal graphite mixture of the day where applicable which was for fine clearance bearings and to add in coarser materials for the rougher surfaces.

The science is still saying the same thing today. Nano plus sub micron and micron in an oil reduces wear more than nano by itself for rougher surfaces.

The all round mix may be causing one problem. On very small clearances as in cam lobe/follower interface the wrong mix and quantity can block the oil entry of the EHD oil film. Here nano should work wonders as it is suitable since we need a smaller partical to enter the film.

So why not nano for cam shaft additives.( Liqui Moly has no nano additive) Well seems the big push by the science was to have the lub. producers on board as of 2014.

3 problems as of 2014: Storage problem , the negative interaction with detergent/ dispersants and black colour. Does not seem to be any break through in these areas yet.
 

boomer1

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Any body on here old enough (I am) to remember Arco Graphite oil? It was their version of motor oil sold with extremely fine graphite particles for reduced engine wear. Apparently it worked but when you opened a new bottle of oil, it was jet black and this turned off the buying public big time. This was sold in the 1970's.
 

Windex

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Seems an interesting concept.

I would think that it was an attempt to compensate for the less sophisticated machining tolerances of the time.

Standard viscosities were 30wt back then, migrating to 20w40, 15w40, 10w30 etc.

with improved manufacturing and machining, were down to 5w20 and 0w20 - oils which would not have provided sufficient viscosity to protect the larger bearing clearances common when these articles were written.

I don't think any modern engine would see any tangible benefit from suspended solid graphite in motor oil.
 

James & Son

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There is lots of liquid derivatives of the anti-ware, such as zinc and antimony, titanium chemically ddp's, etc. and friction modifiers such as boron, molybdenum, tungsten, chemically called the dtc's, etc. These combinations work well as a CJ4 but can not meet the new extra low ash requirements I think this year.

The ashless versions of the above aren't all that great either.

That is why I think the push in 2014 to try and get the nano solids such as molydisulfide, hexagon boride and boric acid ready as they can replace Zddp and are fairly benign to the environment and do not chemically interact with other additives providing options for the formulator.

Not a lot of material on the internet from 2014 to now to know what is happening.
 
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Rob Mayercik

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Any body on here old enough (I am) to remember Arco Graphite oil? It was their version of motor oil sold with extremely fine graphite particles for reduced engine wear. Apparently it worked but when you opened a new bottle of oil, it was jet black and this turned off the buying public big time. This was sold in the 1970's.
Gadzooks, someone else who's heard of that! I think there's a can or two of that stuff up on the shelf in my mother's garage...
 

jjblbi

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I remember...and don't forget to have an old can opener in your toolbox for opening the metal topped, waxed cardboard can!
 

Powder Hound

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...

That is why I think the push in 2014 to try and get the nano solids such as molydisulfide, hexagon boride and boric acid ready as they can replace Zddp and are fairly benign to the environment and do not chemically interact with other additives providing options for the formulator....
No, the zinc compound is a replacement for molydisulfide. The problem with moly is that when it works, it releases sulfur and plates the molybdenum onto the lubricated surface, which then is what wears instead of the original surface. The sulfur, now released, then goes on to get into the intake stream via CCV (PCV in a gasser) and then into the exhaust stream where it poisons the catalyst in the catalytic converter. That also happens to be the big reason behind the push to remove sulfur from fuels.

Ergo, the only place you now find MoS2 is in gearbox lubricants.

Sulfur, while very useful, can't be considered 'benign'. When oxidized and combined with water, it makes sulfuric acid, which causes all kinds of trouble in the atmosphere.

Cheers,

PH
 

James & Son

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No, the zinc compound is a replacement for molydisulfide. The problem with moly is that when it works, it releases sulfur and plates the molybdenum onto the lubricated surface, which then is what wears instead of the original surface. The sulfur, now released, then goes on to get into the intake stream via CCV (PCV in a gasser) and then into the exhaust stream where it poisons the catalyst in the catalytic converter. That also happens to be the big reason behind the push to remove sulfur from fuels.
Ergo, the only place you now find MoS2 is in gearbox lubricants.
Sulfur, while very useful, can't be considered 'benign'. When oxidized and combined with water, it makes sulfuric acid, which causes all kinds of trouble in the atmosphere.
Cheers,
PH
Remember Zddp is also dual purpose and used as an antioxidant to help that molydtc become MoS2 under heat and pressure rather than MoO3 which is an abrasive oxide. As long as MoS2 does not oxidize I believe it is not to acidic although there is no doubt it is not benign( because of the sulfur component). MoS2 in powder form can oxidize as well and become acidic but oxidants are added to prevent this( That would be a good question for Liqui Moly).

While we are on the subject of Molydtc. Have you ever wondered why it is not added to diesel oil. The reason is usually you can't put enough in to make it worth while and meet CJ4 specs. 300 parts of molydtc will only last 150 to 160 hours and that is hardly 10,000 miles and that is if the manufacturer can get enough Zddp in the oil to keep it from oxidizing and turning abrasive. For those running S9000 I would change no later than 10,000 miles.

Edit: My mistake, both Molydtc and MoS2 are not considered enviromentally friendly because of the sulfur like powder hound stated. On BITOG Molakule explains it as well.
https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=261795
 
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tikal

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There is lots of liquid derivatives of the anti-ware, such as zinc and antimony, titanium chemically ddp's, etc. and friction modifiers such as boron, molybdenum, tungsten, chemically called the dtc's, etc. These combinations work well as a CJ4 but can not meet the new extra low ash requirements I think this year.

The ashless versions of the above aren't all that great either.

That is why I think the push in 2014 to try and get the nano solids such as molydisulfide, hexagon boride and boric acid ready as they can replace Zddp and are fairly benign to the environment and do not chemically interact with other additives providing options for the formulator.

Not a lot of material on the internet from 2014 to now to know what is happening.
Thank you very much for sharing this quite interesting memorandum from almost 100 years ago!

Here is a very interesting article from Argonne National Laboratory in cooperation with Valvoline (2013) speaking on the subject:

https://energy.gov/sites/prod/files/2013/11/f4/nanoparticulate-based_lubrication.pdf

And the full research paper:

https://www.osti.gov/scitech/servlets/purl/1097780
 
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