Cermet B, Who has it? How does it make you feel?
05-24-06, 03:45 PM
#52
Originally Posted by doridori-rx7
it's only a holy grail, if the product works, so far they've shown and offered nothing but if's, when's and could be's.
I think you are overooking one the largest benefits of the cermet coating.
A housing with un-machinable scores is garbage. Cost from Mazda? approx. $700 Cost to have the housing coated and resrfaced? $300. Whether or not it provides a more efficient/lnger lasting friction surface will (for me) remain in the air until Joe tears down his engine in the fall.
But the point still remains that the process can save you money - not to mention housings that they no longer manufacture - and that in itself is credit worthy.
05-24-06, 06:33 PM
#54
Originally Posted by Goofy
The problem with the carbide tool theory is that the carbide tools are designed to wear down metal.
Designed to wear down metal is equivalent to designed to eat apex seals. That's not something we actually want, though.
From what I understand the housing hardness and apex seal hardness was designed by Mazda such that they would wear at approximately equal rates, ie: they would fail at the same time, to maximize overall engine life. If Mazda had gone with harder seals, the housings would be chewed up by them and if Mazda had gone with harder housings, they'd eat the seals.
The only part of Cermet that makes up for this is the theory that it's a lower operating friction, saving the seals' lives. Please, think of the baby seals!
Designed to wear down metal is equivalent to designed to eat apex seals. That's not something we actually want, though.
From what I understand the housing hardness and apex seal hardness was designed by Mazda such that they would wear at approximately equal rates, ie: they would fail at the same time, to maximize overall engine life. If Mazda had gone with harder seals, the housings would be chewed up by them and if Mazda had gone with harder housings, they'd eat the seals.
The only part of Cermet that makes up for this is the theory that it's a lower operating friction, saving the seals' lives. Please, think of the baby seals!
Dude, what are you talking about? First, you don't wear something when you machine it. You cut it. Second, the cermet housing has no cutting edge. Tell me, please, how this will wear the apex seals faster? Cermet is NOT abrasive. In fact, it's got less friction and a smoother surface than steel does.
05-24-06, 06:41 PM
#55
Oh, and just to clear things up, CERMET WAS NOT DEVELOPED BY JHB!!!!! it has been in use for years, in the tooling industry. You can find tons of info out there on it. Cermet is no new, magical coating. It's been around for a while.
05-24-06, 07:27 PM
#56
I wish I was driving!
Originally Posted by iceblue
I do not trust kermit so here is some info on cryo. I cryo my entire block evry part of it except the intake manifold and flywheel. I also add 70$ to all my customers rebuilds and I have there apex seals done and housings if new.
What's even better is that you use this on rotor housings, which are made of aluminum, with a metal insert with a chromium coating. The chrome surface is the wear surface.
Cryo-processing affects iron and steel alloys... your own post agrees with this.
Chromium is an element, not an alloy of steel.... so cryo processing rotor housings for a reduction in wear is... simply a waste of money. What possible gains do you expect in increasing the stregth and wear resistance on a part that should never be in contact with any moving parts?
Its nice to see you educated yourself before attacking another proven product and charging other people for a process that will do nothing for them.
05-24-06, 08:11 PM
#57
Boost in..Apex seals out.
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Originally Posted by scathcart
What possible gains do you expect in increasing the stregth and wear resistance on a part that should never be in contact with any moving parts?
Originally Posted by iceblue
Another benefit of Cryogenic treatment is that the metal becomes a very efficient dissipated of heat. This means engines, transmissions, disk brakes, and cutting tools run much, much cooler.
Hmm....
05-25-06, 06:55 AM
#59
Our Cermet A&B coatings
surface micro-hardness of up to 2000HV Macro hardness of 58-62 Rc chrome 1100HV
friction coefficient between 0.03-0.1 chrome 0.4 after UMC coating is worn off
bond strength > 12,000 psi
density >99.5% induced micro-channels and porosity
surface micro-hardness of up to 2000HV Macro hardness of 58-62 Rc chrome 1100HV
friction coefficient between 0.03-0.1 chrome 0.4 after UMC coating is worn off
bond strength > 12,000 psi
density >99.5% induced micro-channels and porosity
Mazda Cermet specifications (R26B)
Hardness (Hv) = 1700
Bending strength (MPa) = 1200
Fracture toughness (MPam1/2) = 6
Thermal shock resistance (deltat) = >550
Density (g/cm^3) = 3.3
05-25-06, 07:47 AM
#60
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Originally Posted by shm21284
Dude, what are you talking about? First, you don't wear something when you machine it. You cut it. Second, the cermet housing has no cutting edge. Tell me, please, how this will wear the apex seals faster? Cermet is NOT abrasive. In fact, it's got less friction and a smoother surface than steel does.
The theory following the lines of "cermet is better for machining tools means cermet is better for housings" relies on some unstated assumption. You prominently stated that cermet is mostly used for cutting tools, implying that cermet helps tools cut better. The only applicable information from that is that you'd, by association, imply that our housing would now cut better.
What I mean to ask is: What property of cermet is it that makes tools cut better that would make our housings wear down less and wear our apex seals less. Or is it that cutting tools don't use cermet to cut better, but to wear down less? Do they make cutting harder, losing time to increase tool lifespan?
And since you've decided to make a technical reference to the definition of wear vs. cut, whereas I was trying to stay more in layman's terms, what is the denotative difference between "wear" and "cut" and how does our housing-seal barrier cause a "wear" condition whereas a tool causes a "cut" condition?
05-25-06, 09:32 AM
#62
Engine, Not Motor
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I've been told by several very experienced rotary builders (names withheld to avoid flamming 
) that cryotreating any part of the rotary is essentially pointless. The eccentric shaft is already very hard steel that exhibits great wear characteristics, treating the bearings apparently makes them too brittle and Mazda spent an insane amount of money and research designing the apex seal compounds and inner surface of the housings and irons to obtain the proper wear and sealing characteristics. Changing any of those things does not seem to be a good idea...
This is stuff that I have been told by experienced builders, not proven to myself. I have no data to back this up. Take that for what it's worth. But I've also never actually heard of anyone cryo treating rotary parts for any reason....
) that cryotreating any part of the rotary is essentially pointless. The eccentric shaft is already very hard steel that exhibits great wear characteristics, treating the bearings apparently makes them too brittle and Mazda spent an insane amount of money and research designing the apex seal compounds and inner surface of the housings and irons to obtain the proper wear and sealing characteristics. Changing any of those things does not seem to be a good idea...This is stuff that I have been told by experienced builders, not proven to myself. I have no data to back this up. Take that for what it's worth. But I've also never actually heard of anyone cryo treating rotary parts for any reason....
05-25-06, 10:21 AM
#63
Some information I found.
If you can get to it (I did through my college library system):
http://www.sciencedirect.com/science...eb74e9ee#SECX7
The above results confirm that HVOF-sprayed coatings, especially cermet ones, are a reliable alternative to electrolytic hard chrome plating. In particular, in a two-body unlubricated wear condition, the HVOF-sprayed coatings outperform EHC coatings in wear resistance and also display a lower friction coefficient, which implies less heating and energy dissipation during the components relative motion and/or the possibility to operate with limited lubrication. In two-body sliding conditions, HVOF-sprayed cermet coatings are able to form tough, compact and very hard surface films (tribofilms), consisting in carbide particles strongly incorporated in a plastically deformed metal matrix and slightly protruding. This film can be difficultly removed, even when high contact pressures are applied; thus, once the film is formed, the coating is protected from further damage. Metallic coatings are also able to form tribofilms, but the only hard particles they can incorporate are wear debris. EHC coatings, instead, cannot form a smooth and compact tribofilm; with high contact pressures this film is easily fractured and partly removed. Therefore EHC coatings undergo higher mass losses and develop higher friction coefficients. Three-body abrasion, instead, is a severe wear test for HVOF-sprayed coatings, even if WC-17% Co cermet coating behaviour is comparable with the best EHC coatings, because it acts on their weakest links (splats cohesion), causing material removal and preventing the tribofilm formation. The results also indicate significant differences between the studied varieties of EHC coatings: even if the bath conditions are kept unchanged, the substrate preparation technique, the use of double-plating, and the possible post-deposition treatments heavily affect the coating performance. Thus, different EHC varieties are fit for different wear conditions.
These conclusions also point out to the fact that the coating choice for a component or an application requires preliminary a specific and detailed study of the wear conditions, and that more fundamental research work on coatings performance in various wear situations is needed to provide the industrial designer a wide range of data to lead him to the choice of the right coating.
These conclusions also point out to the fact that the coating choice for a component or an application requires preliminary a specific and detailed study of the wear conditions, and that more fundamental research work on coatings performance in various wear situations is needed to provide the industrial designer a wide range of data to lead him to the choice of the right coating.
http://www.sciencedirect.com/science...eb74e9ee#SECX7
05-25-06, 11:13 AM
#64
Originally Posted by Goofy
The theory following the lines of "cermet is better for machining tools means cermet is better for housings" relies on some unstated assumption. You prominently stated that cermet is mostly used for cutting tools, implying that cermet helps tools cut better. The only applicable information from that is that you'd, by association, imply that our housing would now cut better.
Originally Posted by Goofy
What I mean to ask is: What property of cermet is it that makes tools cut better that would make our housings wear down less and wear our apex seals less. Or is it that cutting tools don't use cermet to cut better, but to wear down less? Do they make cutting harder, losing time to increase tool lifespan?
As for housings, the benefits are obvious. We don't have a cutting edge on the housing; rather, the apex seal has a lower pressure. No focussed point of force. So, there is wear, not cutting, happening (see below for a more in depth definition). Cermet has a much lower coefficient of friction than Mazda's housing surface. Because of this, there is less wear on the apex seals, because of the lower friction. Again, looking at the molecular level, the steel will look jagged, where the cermet will look much smoother. The cermet may even cause the steel to be micropolished, allowing for even less friction yet. Cermet also allows for less heat transfer, so more heat is used in combustion; therefore, more power is made. This also effectively increases the capacity of the cooling system, because less heat makes its way to the cooling water in the housings and cooling oil in the rotors (if you were to coat the rotors).
Originally Posted by Goofy
And since you've decided to make a technical reference to the definition of wear vs. cut, whereas I was trying to stay more in layman's terms, what is the denotative difference between "wear" and "cut" and how does our housing-seal barrier cause a "wear" condition whereas a tool causes a "cut" condition?
Cut - According to dictionary.com "To penetrate with a sharp edge; strike a narrow opening in." Requires a cutting edge. According to an experienced machinist, The pressure of the cutting edge is so high (focussed to a point), that it causes the metal to actually shear. Each chip that flies off the workpiece is a result of the shear. More literally, cutting occurs with a highly focussed force (high pressure), and produces much larger chips (wearing away at something produces a very very fine dust of metal, not chips).
05-25-06, 11:21 AM
#65
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friction coefficient between 0.03-0.1
0.03?? that's better then teflon and DLC... I seriously doubt a metal based (0.7 ) substrate product has a 0.1 CofF. never mind lower. DLC is 0.1 and that pretty much is the top of the coatings food chain.
Also why are these people still using outdated HV applicators, det guns are faster, cheaper and don't need to anywhere near as invasive to the material being sprayed..
this is all crap, they are pulling numbers out of thier ***, and as for this whole, ' protecting thier product like everyone else' that crap, ANY coatings company worth it's salt is more then happy to provide detailed info on it's products.. and were talking companies that compete for business in the F1/NASCAR world.. CALICO, Bekaert, NCT.
At this point I doubt I'd ever do business with them, even if a customer requests the coatings. 'Shady and suspect ' are two words that instantly come to mind everytime they do or say something.
05-25-06, 11:52 AM
#68
Originally Posted by doridori-rx7
0.03?? that's better then teflon and DLC... I seriously doubt a metal based (0.7 ) substrate product has a 0.1 CofF. never mind lower. DLC is 0.1 and that pretty much is the top of the coatings food chain.
Also why are these people still using outdated HV applicators, det guns are faster, cheaper and don't need to anywhere near as invasive to the material being sprayed..
this is all crap, they are pulling numbers out of thier ***, and as for this whole, ' protecting thier product like everyone else' that crap, ANY coatings company worth it's salt is more then happy to provide detailed info on it's products.. and were talking companies that compete for business in the F1/NASCAR world.. CALICO, Bekaert, NCT.
At this point I doubt I'd ever do business with them, even if a customer requests the coatings. 'Shady and suspect ' are two words that instantly come to mind everytime they do or say something.
Also why are these people still using outdated HV applicators, det guns are faster, cheaper and don't need to anywhere near as invasive to the material being sprayed..
this is all crap, they are pulling numbers out of thier ***, and as for this whole, ' protecting thier product like everyone else' that crap, ANY coatings company worth it's salt is more then happy to provide detailed info on it's products.. and were talking companies that compete for business in the F1/NASCAR world.. CALICO, Bekaert, NCT.
At this point I doubt I'd ever do business with them, even if a customer requests the coatings. 'Shady and suspect ' are two words that instantly come to mind everytime they do or say something.
05-25-06, 12:03 PM
#70
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I meant to imply having JHB coat our engine components theoretically gives us these benefits, since there is no technical information section disclosing their testing on their website.
05-25-06, 12:29 PM
#71
Dori - I dont see the motivation to get all these numbers? I mean say JHB came out and said "the coating has X firction coefficient and Y tolerance and Z ppm of carbide or whatever......its still not going to tell you JACK about how it performs in the real world. You seem tobe basing the conclusion that the coatings don't work on the fact that you can't get these finite figures.
Just hang tight and wait until we get this motor torn back down in the fall and you'll have all the real world knowledge of how they perform in a rotary.
Just hang tight and wait until we get this motor torn back down in the fall and you'll have all the real world knowledge of how they perform in a rotary.
05-25-06, 12:45 PM
#73
Originally Posted by doridori-rx7
0.03?? that's better then teflon and DLC... I seriously doubt a metal based (0.7 ) substrate product has a 0.1 CofF. never mind lower. DLC is 0.1 and that pretty much is the top of the coatings food chain.
You're also forgetting that most cermets are composed more of ceramics. They're usually less than 20% metal.
It also depends on what kind of coefficient of friction you're looking at. In a greasy environment when looking at sliding, steel can have a coefficient of friction on steel of as low as .029.
On a lubricated surface, zinc on zinc coefficients of friction are around .04. Roughly the same as Teflon.
Overall, NFC (Near Frictionless Carbon) has the lowest coefficient of friction of any material (<.001). Let's just use that
.
05-25-06, 01:36 PM
#74
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Not sure where you get your coating info from but Cof F and wear ratings in high stress /heat environs the DLC is the best.
JHB has claimed it's an 'in house (developed)' product in an older thread in the Canadian section..
I want the nubmers and so should the rest of you, your buying this stuff and building engines with it and you have no clue as to what seals to use and how they are going to behave? why, becuse they don't even know.. they've done NO testing what so ever. Using tool coatings to extrapolate from is at best grasping at straws.
So instead of paying money to a company that is charging a premium and not providing even the most basic of numbers, nor it seems caring much about the fact.. I can go get a 3 micron Me-C:H sp^3 coating that I know the numbers for it would be very simple to then match a coating to the apex seals that would provide the lowest friction, heat and with tabled wear numbers I can predict approximate wear.
with the knowledge that JHB could easily supply it would allow the customer to choose the right product.. who knows maybe thier coatings are not as favorable as a resurface in CrAlTiN (Cromium aluminum Titanium nitride ).. We don't knwo becuse they obviosuly don't want anything published about it.
JHB has claimed it's an 'in house (developed)' product in an older thread in the Canadian section..
I want the nubmers and so should the rest of you, your buying this stuff and building engines with it and you have no clue as to what seals to use and how they are going to behave? why, becuse they don't even know.. they've done NO testing what so ever. Using tool coatings to extrapolate from is at best grasping at straws.
So instead of paying money to a company that is charging a premium and not providing even the most basic of numbers, nor it seems caring much about the fact.. I can go get a 3 micron Me-C:H sp^3 coating that I know the numbers for it would be very simple to then match a coating to the apex seals that would provide the lowest friction, heat and with tabled wear numbers I can predict approximate wear.
with the knowledge that JHB could easily supply it would allow the customer to choose the right product.. who knows maybe thier coatings are not as favorable as a resurface in CrAlTiN (Cromium aluminum Titanium nitride ).. We don't knwo becuse they obviosuly don't want anything published about it.
Originally Posted by My5ABaby
Teflon's usual coefficient of friction is .04. DLC's is ~.1. How does that make DLC the top of the coating's foodchain...
You're also forgetting that most cermets are composed more of ceramics. They're usually less than 20% metal.
It also depends on what kind of coefficient of friction you're looking at. In a greasy environment when looking at sliding, steel can have a coefficient of friction on steel of as low as .029.
On a lubricated surface, zinc on zinc coefficients of friction are around .04. Roughly the same as Teflon.
Overall, NFC (Near Frictionless Carbon) has the lowest coefficient of friction of any material (<.001). Let's just use that.
You're also forgetting that most cermets are composed more of ceramics. They're usually less than 20% metal.
It also depends on what kind of coefficient of friction you're looking at. In a greasy environment when looking at sliding, steel can have a coefficient of friction on steel of as low as .029.
On a lubricated surface, zinc on zinc coefficients of friction are around .04. Roughly the same as Teflon.
Overall, NFC (Near Frictionless Carbon) has the lowest coefficient of friction of any material (<.001). Let's just use that
.
05-25-06, 02:00 PM
#75
Passing life by
Every builder has there own thing. I had been told by very renowned and experienced builders that cryo treating internals are superb. It does not make the metal harder it makes it stronger wile providing cooling properties. I would say the end results of these debates is like 2mm vs 3mm do what you must.