36 replies to this topic

[red300zx99]

Was wondering if anyone knew what materials are used in the driveline of F1 cars. We are about to try a titanium ring and pinion, friction aside was wondering if anyone knew of any material better suited for this application.

[desmo]

Going from memory, I remember being told that most of the the transmission/diff internals are made from 300M steel in F1. I would hazard a guess that using Ti bits here would be begging for trouble.

[red300zx99]

What kind of trouble do you fear with Ti gears? Again friction aside, we believe we have a solution for that.

[VAR1016]

Perhaps Jaguar has the answer: http://www.atlasf1.c...p/id/1209/.html

Oh dearie, dearie, me!!

PdeRL

[desmo]

Ti hasn't in the past been noted for its outstanding tribological properties relative to steels. Perhaps developments in surface treatment for Ti alloys have advanced to the point where highly loaded Ti gearsets are suitable for more than brief drag racing duty. I just doubt the upsides- presumably a small lessening of mass- would outweigh the potential for grief here. It seldom pays to break new ground in materials for motorsports. If the pieces are available from a reputable firm and that firm's engineers are confident that the pieces are up to the proposed use though, I guess it might be worth a try provided the potential benefits are substantial. But I'm conservative, I consider the primary goal of transmission components to be simply doing what is asked without breaking. Anything else is decidedly secondary.

[J. Edlund]

Originally posted by desmo
Ti hasn't in the past been noted for its outstanding tribological properties relative to steels. Perhaps developments in surface treatment for Ti alloys have advanced to the point where highly loaded Ti gearsets are suitable for more than brief drag racing duty. I just doubt the upsides- presumably a small lessening of mass- would outweigh the potential for grief here. It seldom pays to break new ground in materials for motorsports. If the pieces are available from a reputable firm and that firm's engineers are confident that the pieces are up to the proposed use though, I guess it might be worth a try provided the potential benefits are substantial. But I'm conservative, I consider the primary goal of transmission components to be simply doing what is asked without breaking. Anything else is decidedly secondary.

This also limit for example the use of two titanium valve springs per valve.

[saudoso]

Originally posted by red300zx99
Was wondering if anyone knew what materials are used in the driveline of F1 cars. We are about to try a titanium ring and pinion, friction aside was wondering if anyone knew of any material better suited for this application.

I'm interested in the "friction aside" stuff. My kwnoledge of materials is realy small, but I've been to a workshop where some PDV"(Physical Vapour Deposition) materials where presented. Those are usually used in tooling (like plastic molds, cutting tools and so on). They are remarkable for their hardness and low friction rates. The materials are based on Ti, with the adiction of Chrome Carbon, as far as I remember. Are those currently used in drive trains or any other parts?

[red300zx99]

Well we've been testing with a few Winston Cup teams a plating process on ring and pinions. We were able to achieve ~10hp at the rear wheels with everything else in the rear end standard except for our plated ring and pinion over their rear end with this and that, so more improvement is to be expected with polished bearing and the likes. So about 10hp over the peak previous rear wheel hp, and about 7hp better on coastdown, a test for driveline friction. About 30 pulls on our gear and 20 something odd pulls on their equipment, trying to keep things constant and get a good average to compare things. So with our plating process we were able to reduce friction considerable, 10hp in WC is a huge gain, especailly for the big tracks daytona talladega and the like. So our thinking now is plate a lighter gear, titanium, for improved driveline efficiency, havent found any oneelse whos done it before, our thinking is because of the friction created by such a gear, also heard of titanium embrittlement and such, but rear ends dont usually operate in the heat range that this occurs. About coating such a casidium and such it doesnt seem to play nicely with high point loads, something that read end gears will produce. This is why I ask if anyone else sees a concern in making Ti gears, or suggestions of materials that would be even better suited then Ti.........don't want to spend the $$$ on getting a Ti gear made if we know it will fail before we start this process, value the opinion of all, so shoot it down, praise it, or whatever else you do and you will be appreciated for it

[desmo]

Originally posted by red300zx99
Well we've been testing with a few Winston Cup teams a plating process on ring and pinions. We were able to achieve ~10hp at the rear wheels with everything else in the rear end standard except for our plated ring and pinion...

Let's arbitrarily but generously assume that this "plating" process can cut frictional losses by half vs untreated parts. Let's also accept the 10bhp increase in rear wheel power due to reduced friction is real. Wouldn't this perforce mean that the old ring and pinion set- presumablty representing the very best previous technology- were turning 20bhp into waste heat all by themselves? Wow.

[JwS]

I don't know exactly what kind of gears they are running, but standard hypoid diff. gears have quite a bit of sliding action, that is why special lubes are generally wanted, so 20 hp from a winston engine (how many hp? 500+??) sounds very likely.
Titanium is relatively flexy, compared to the typical materials used in those gears, and the loadings are quite high, so I would be concerned about deflection of the gears causing mialignment. That of course doesnt mean Ti wouldn't be a good material, as usual, when the material is changed the design may have to change too.
JwS

Neat stuff though!

[red300zx99]

Non-restricted WC motors are producing in the 800-900hp range, restrictor plate motors less. the 10hp gain was made on a restrictor plate motor, still a gain of ~1% is huge in any racing series. After some more conclusive testing transmissions are next, followed engine internals. This should be fun, but if we could get a Ti gear or something similar to work then greater gains can be found from the rear end alone. All I gotta say is military technology rocks

[McGuire]

Originally posted by red300zx99
Non-restricted WC motors are producing in the 800-900hp range, restrictor plate motors less. the 10hp gain was made on a restrictor plate motor, still a gain of ~1% is huge in any racing series. After some more conclusive testing transmissions are next, followed engine internals. This should be fun, but if we could get a Ti gear or something similar to work then greater gains can be found from the rear end alone. All I gotta say is military technology rocks

The restrictor-plate engine produces only around 415 bhp...hence all the interest in eliminating engine and driveline losses...platings, coatings, metal finishes, low-vis and low-drag lubricants...this area is suspected to be one of the "speed secrets" of the DEI cars on the plate tracks.

[dosco]

Originally posted by red300zx99
All I gotta say is military technology rocks

Huh? Whaddya mean?

[dosco]

What ti alloy are you considering?

What temperature is the gearset supposed to work in?

Can you change the dimensions of the internals? Or are you restricted to replacing for equal size?

[Greg Locock]

I've got figures for the effciiency of a diff,I can believe 10 hp. For a good production diff the efficiency at full throttle lies between 82 and 91 %, depending on which gear is being used.

[Lukin]

Just out of interest, why would the diff effeciency depend on what gear is being used?

The only possible reason I can think of is the higher the gear the higher the speed and the more air flow under the car which would cool the diff.

[JwS]

The effect of gears is torque muliplication, so in first gear the engine torque is multiplied, while in higher gears it is less.
JwS

[red300zx99]

3.07:1 ring and pinoin, as was said the torque multiplication causes the change in power gained. Forget the actual equation for torque at the wheels because of driveline efficiency, but it's in Gillespie's book if you need to know. Also the car was ran at ~215mph if thats any help to anyone.

Military technology rocks as this plating was originaly produced for solutions for the sand in the middle east, can't say much more about what they use it for, am allowed to say that the M-16 in the American military is plating the barrels with this stuff. We just got lucky, we are located in northern Virginia, so defense contractors everywhere. It's amazing the technology we see just from living in the area and knowing the right people, people with big mouths. Just so happened that a chair holder to one of these companies , and he is a gear head and a friend of the company. So now we have the exclusive rights to sell this stuff to the automotive industry, except for penske, damn chair holder knows him too Now the military is doing a study to see if it's feasable to make part of the M-16 out of Ti, and plating it, so light goes off in head, why not driveline parts too.

[dosco]

Originally posted by red300zx99
Military technology rocks as this plating was originaly produced for solutions for the sand in the middle

Interesting. Any URLs or other information?

FWIW, I'd like to get in touch with this guy.....my company might be able to use the stuff too. PM me.....

[red300zx99]

I will post a download or something soon with more info, sorry been only testing the plating so far and little marketing info has been put together yet, but I will start work on it as soon as I goto work.

[rgsuspsa]

As an engineer formerly in the aerospace industry, I have learned the language of pretenders,
and such language is prominent in this thread.

[desmo]

Originally posted by rgsuspsa
As an engineer formerly in the aerospace industry, I have learned the language of pretenders,
and such language is prominent in this thread.

I'd love to hear your thoughts as an engineer on the subject. Posts are welcome here from engineers and non-engineers alike, if you have an objection to any specific assertions put forth why not address them directly?

[Lukin]

Originally posted by JwS
The effect of gears is torque muliplication, so in first gear the engine torque is multiplied, while in higher gears it is less.
JwS

G'day JWS,

I understand the torque multiplication through the gearbox, but when looking at the diff, wont the effeciency simple be a function of what power goes (torque x angular velocity) in and what power comes out? It doesnt matter the multiplication through the final drive ratio.

Wait, are we talking about just the diff or the drievtrain as a whole. In the drivetrain as a whole I can understand how the losses will vary in different gears due to the different gear sizes (and therefore different levels of rotating inertia).

But as for the diff, can someone explain how the diff effeciency changes with the gear.

Cheers,
Jas

[Lukin]

Just had another thought. Could the effeciency more vary with the actual speed of the car in the terms of the interaction of the oil in the diff. I may be way off, but if the drag that the viscosity of the oil produces in rotation doesnt increase linearly with the shaft speed, the power loss from viscous drag could change with the speed of the input shaft and therefore effec the effeciency. Is that a possibility. I cant for the life of me figure out why diff effeciency would vary with gear. Oh well, going to hit the turps, might have a brainwave then. More than likely not.

[Greg Locock]

Wow, that'll teach me to be cryptic.

The efficiency of the diff depends primarily on the torque through it, In first gear it sees something like 3 times the torque in 4th gear.

Actually those results are from a dyno test, not in-vehicle.

[perfectelise]

Originally posted by red300zx99
.. can't say much more about what they use it for, am allowed to say ..

Originally posted by rgsuspsa
As an engineer formerly in the aerospace industry, I have learned the language of pretenders,
and such language is prominent in this thread.

[ZoRG]

Greg, do you perhaps know what a transverse mounted diff efficiencies are?

[Greg Locock]

No. The same causes of inefficiency will be there, so I'd expect the characteristic to be the same. So far as I can tell the losses are (a) static friction, (b)load dependent friction, © losses associated with misalignment of the gears, due to deflection in the structure, shafts and gears.

[Lukin]

Originally posted by Greg Locock
...So far as I can tell the losses are (a) static friction, (b)load dependent friction, © losses associated with misalignment of the gears, due to deflection in the structure, shafts and gears.

Cool, Ta, Didnt think of that.

[hydra]

Going slightly off topic,
What gear materials do (performance) automotive gears use, and to what level are they usually hardened? A quick web search turned up 9310 steel, as opposed to the mechanically superior 4340... Any idea why that is?

[12.9:1]

red;
Sounds like your coating is low friction? does it effect hardness?
Hardness being essential for any gear.
Are you talking about 'Nitrogen Diffusion Hardening' ? If not perhaps you should look into this impressive tech, hardnesses exceeding 60 - Rockwell-C, with penetration as deep as 0.25mm, and without a propensity for cracking even when flexed. Add a coating such as DLC and . . . . . .

Though as this gear is essentially bolted to tire/wheel/axle/rotor, saving a few ounces with Ti can't seriously be a priority.

[red300zx99]

12.9:1, this is not a coating but a plating. An engineer from a team was concerned at first as the process of plating the gears has a step of heating the part to a certain level too let the plating cure. It's not 'Nitrogen Diffusion Hardening' but the plating is harder then the metal, have numbers on the rockwell, again will post them in the morning at work. PerfectElise and rgsuspsa, trust me I understand you skeptism, we've encountered it with just about everyone we have talked too. Our deal to them, so far, is to buy the gears from them, plate them at our expense and to also pay for the testing to prove our product. All said and done, the only thing that we have botched is a bearing that we plated, without taking it apart first, which lead to a substantial increase in friction and heat. So we're stayin out of the bearing buisness until we can get a manufacturer to allow us to plate the bearing prior to assembly. But back to the teams that have gone along with our testing, we have improved effeiciency compared to their normal gears. They just don't like the fact that we wont sell them back their gears that we plated just yet. Still testing and improving, and finding out which applications we can improve, then to the pricing matrix and so on. But believe it or not thats fine with me. Snake oils come and go, the only proof I can give is for you to see it with your own 2 eyes

[dosco]

Originally posted by rgsuspsa
As an engineer formerly in the aerospace industry, I have learned the language of pretenders,
and such language is prominent in this thread.

FWIW, I agree with your skepticism. Which is why I've asked for more info.

Additionally, I work at a place that has use for coatings, plating, etc etc. So I'd also like to test the stuff, to see if its true.

My thought, though, is that it is BS.

[red300zx99]

Info on it's way, sorry for the delay.

Dosco, whats your application, and how would you test it. If you are willing to share test data then we are willing to give you a very reasonable rate(maybe even free) on plating whatever it is you need plated for your test. As I said I understand a naysayer, espcially in this buisness, and even more so to someone who butchers the spelling of everyother word he types, but bring it on, we are here to prove our product. Test it and if it doesn't do what I say then bash the product all you want, but from the testing we have done that has yet to happen

[RDV]

Seeing as specific stiffness is the same (give or take a couple of decimal points) for steel, ally and Ti, dont really see the point in this , as size and geometry will have to change to suit torque applied... why not just use surface treatment on steel? same size Ti ring would wobble all over the place, hence increasing friction and negating advantage.... increasing size and changing gear profile goes into new areas, V1.0 applications can tend to bite hard if making wrong assumptions....

[red300zx99]

Why would a Ti gear wobble all over the place?

[desmo]

Ti's (non specific) modulus of elasticity is considerably lower than steel's.