Friction Modifiers only reduce friction...not wear

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Interesting info on the net: • Antiwear agents: There are times when the lubricating film breaks down, so the antiwear agents have to protect the metal surfaces. A zinc and phosphorus compound called ZDDP is a long-used favorite, along with other phosphorus (and sulphur) compounds. If you musts know, ZDDP stand for zinc diakyl dithiophosphate. • Friction modifiers: These aren't the same as antiwear agents. They reduce engine friction and, so, can improve fuel economy. Graphite, molybdenum and other compounds are used.
 

MolaKule

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Interesting, but not quite correct. Moly and ZDDP are both friction reducers and anti-wear agents. See the Interesting Article section on Friction Modifiers and anti-wear additives.
 

pedaltothemetal

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quote:
Originally posted by MolaKule: Interesting, but not quite correct. Moly and ZDDP are both friction reducers and anti-wear agents. See the Interesting Article section on Friction Modifiers and anti-wear additives.
But when Bob Lancaster from Torco tested the ZDDP at the boundry layer, it caused more friction while reducting wear. Thus the addition of Friction Modifiers to conteract that. I'm certain the oils that don't have moly, then must have graphite or other compounds in their proprietary additives.
 

MolaKule

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It is my understanding that Lancaster didn't do any testing, he only restated someone else's comments. All base oils reduce friction. Friction modifiers reduce the boundary friction even more. Moly, antimony, borate esters, ZDDP, all reduce friction as well as provide anti-wear properties in the boundary lubrication regime. If you somehow had a dry layer of zinc between two moving surfaces, sure it would increase in friction, but that's not what happens. Borates and calcium's can also reduce friction.
 

pedaltothemetal

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The Torco MPZ is a witches' brew of stuff like organic molybydenum derivatives, phosphated esters, and phosphated zinc which is higly polarized and magnetically attacts itself to the iron parts of an engine. Torco claims that it won't let go because the iron also chemically absorbs the MPZ. Who knows!
 

MolaKule

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"magnetically attacts itself to the iron parts of an engine...." No, it doesn't do that. The moly, ZDDP, and phosphate esters bond themselves to the metal surface via ionic bonding (through the sulfur molecules) and form various organometallic layers (about 3 layers) which act as a plastic flow when contact pressures (high loads) are present. The Torco MPZ is nothing new, just a combination of moly, TCP, and ZDDP. TCP has been used for years in jet engine (ester) lubes as an anti-oxidant and as an extreme pressure additive.
 
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Molakule I have heard this same story before and I just don't get it.....so maybe you can explain it for me. In my view a friction modifier HAS to reduce wear. Think of it as a piece of wood and sand paper. When you are sanding wood, there is a huge amount of friction thus causing the sandpaper to eat away the wood (this would be the wear on the wood). Now if you put, say oil on the wood, then the sandpaper will not sand as much, so it (the oil and it’s additives) effectively reduced the wear and the friction at the same time. Even plain oil without any additives would be a friction reducer and an anti wear agent at the same time. Doesn’t this apply to the friction between metals also? Like I said, how can an additive be one but not the other? Ps: I just though of something, thick oil can reduce wear but not friction if it is thick enough. Thick oil is hard to move and might act as glue sometimes. But any other than that??????? Thanks, Rick [ January 02, 2003, 06:56 PM: Message edited by: Last_Z ]
 

pedaltothemetal

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quote:
Originally posted by MolaKule: "magnetically attacts itself to the iron parts of an engine...." No, it doesn't do that. The moly, ZDDP, and phosphate esters bond themselves to the metal surface via ionic bonding (through the sulfur molecules) and form various organometallic layers (about 3 layers) which act as a plastic flow when contact pressures (high loads) are present. The Torco MPZ is nothing new, just a combination of moly, TCP, and ZDDP. TCP has been used for years in jet engine (ester) lubes as an anti-oxidant and as an extreme pressure additive.
You are always so sure of yourself. [Smile] Are you an oil engineer, or just did the research to form your own opinion. Right now I'm trying to form my own opinion, but everytime I do it I get second opinions to confuse me again. [Confused]
 

MolaKule

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Last_Z, Good question. I don't recall anyone saying that Friction Modifiers do NOT reduce wear. Both FM's and AW/EP's do reduce wear; the difference between AW's and FM's lies in their mechanical properties. Friction Modifiers and AW/EP's are terms applied to classifications of different additives. Antiwear/EP's are semiplastic deposits (heavy duty films) which are hard to shear off. FM films consist of orderly, closely packed arrays of molecules (multimolecular whiskers) loosely adhereing to each other. The outer layers of the FM films can be sheared off more easily, allowing for a low coefficient of friction. AW/EP additives deposit a heavier film and act by becoming plastic under heavy loads. This prevents scuffing and seizing. So yes, they both prevent wear, but under the differing conditions of boundary lubrication. As stated elsewhere, many FM's are also AW/EP's as well. Hope that helps. [ January 03, 2003, 10:12 PM: Message edited by: MolaKule ]
 

MolaKule

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Pedal, I am by training a Physicist, with a minor in Physical Chemistry, and work as a Systems Engineer in Advanced Propulsion Systems and Thermodynamics, dealing with tribology and lubrication formulation. Our group works with the chemical companies to develop advanced lubrication fluids for aerospace. I attempt to keep current on the latest advances in gas and diesel engine design, additive technology, and new lubrication fluids as much as possible. If I don't know an answer to a question, I go to the university library (where I also teach) and try to find an answer. Earning an advanced degree doesn't make one an expert, it just teaches you how to learn and organize your research. I really like this board because people here are laid back, good natured, inquisitve, and like the "No-spin" attitude of most of it's members. Edit: Most of my comments come from years of research and practical experience. I am first of all, a grease monkey that likes to design and build hydraulic systems, and rebuild engines in my spare time! [Big Grin] BTW, my grandson is also becoming a little grease monkey as well! He is learning wrench sizes at the moment! [Wink] [ January 03, 2003, 01:24 AM: Message edited by: MolaKule ]
 
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quote:
by MolaKule
I am by training a physicist, with a minor in Physical Chemistry, and work as a Systems Engineer in Advanced Propulsion Systems and Thermodynamics, dealing with tribology and lubrication formulation. Our group works with the chemical companies to develop advanced lubrication fluids for aerospace. I attempt to keep current on the latest advances in gas and diesel engine design, additive technology, and new lubrication fluids as much as possible. If I don't know an answer to a question, I go to the university library (where I also teach) and try to find an answer. Earning an advanced degree doesn't make one an expert, it just teaches you how to learn and organize your research. I really like this board because people here are laid back, good natured, inquisitve, and like the "No-spin" attitude of most of it's members. Most of my comments come from years of research and practical experience. I am first of all, a grease monkey that likes to design and build hydraulic systems and rebuild engines. Lesson #2>>>>>>>>>Refer to Lesson #1! Mark [Big Grin]
 

MolaKule

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Pedal, "Right now I'm trying to form my own opinion, but everytime I do it I get second opinions to confuse me again." I know it's confusing, trying to sort out opinions verses fact. One does have to form his/her own opinion when faced with diverse information. Hang in there, we are all still learning. [Cheers!] [Cheers!]
 
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Yes, Molakule is a huge asset to this site and a genius.....Physics is a very hard subject as well as chemistry. [Smile] I couldnt do it, thats for sure! On a negative note, I bet your a Steeler's fan!! Go EAGLES!! [Big Grin] [ January 03, 2003, 11:59 PM: Message edited by: buster ]
 
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quote:
buster Member Member # 576 posted January 03, 2003 11:51 PM -------------------------------------------------------------------------------- Yes, Molakule is a huge asset to this site and a genius.....Physics is a very hard subject as well as chemistry. I couldnt do it, thats for sure! On a negative note, I bet your a Steeler's fan!! Go EAGLES!! [ January 03, 2003, 11:59 PM: Message edited by: buster ] -------------------------------------------------------------------------------- Posts: 263 | From: NJ | Registered: Nov 2002 | NEGATIVE NOTE? [No no] I'm sure you mean POSITIVE! [Big Grin] Mark [Wink]
 
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