F1technical.net

IIRC Ferrari used ceramic coating for the cylinder walls and pistons in their V10's. I remember reading back then about Shell developing special lubricants as the traditional ones lead to the coating delamination.
Lon time since though, may be wrong.
I think ceramic parts were outlawed with the V8 engine rules.

Yes JA is getting a little confused there. Last week about a dozen journos were taken on a tour of the Mercedes AMG powertrain factory (what was MBHPE). I was amongst that group.
We were shown a range of F1 engine parts, including a current V8 piston. It was totally coated in DLC, which along with the raduissed edges may have appeared to be ceramic. But obviously not, as the rules demand alu pistons.

scarbs wrote:Yes JA is getting a little confused there. Last week about a dozen journos were taken on a tour of the Mercedes AMG powertrain factory (what was MBHPE). I was amongst that group.
We were shown a range of F1 engine parts, including a current V8 piston. It was totally coated in DLC, which along with the raduissed edges may have appeared to be ceramic. But obviously not, as the rules demand alu pistons.

Interesting scarbs, funny there is no ban on DLC, would you have any idea what the oppsite surface in the liner could be?

A bit dumb question:
DLC - is this for Diamond Like Carbon?

Dragonfly wrote:A bit dumb question:
DLC - is this for Diamond Like Carbon?

It is indeed, often used as coating on balls, rollers and raceways for bearings, in order to reduce wear and friction.

http://www.skf.com/portal/skf/home/indu ... tId=870770

Thanks, I lack knowledge of a lot English abbreviations and try to find them googling, but can't always be sure.

scarbs wrote:We were shown a range of F1 engine parts, including a current V8 piston. It was totally coated in DLC, which along with the raduissed edges may have appeared to be ceramic.

To be precise was the interior and piston crown also coated with DLC? What was the general color and was it uniform over the complete piston. Was DLC stated as the coating by company reps?

Brian

You want fries with that...Brian?

xpensive wrote:Interesting scarbs, funny there is no ban on DLC, would you have any idea what the oppsite surface in the liner could be?

1) Although things do change, nickel/silicon carbide composite coatings (ceramic) were/are generally the best solution for the bore coatings. Have you heard of anything better being developed?

TiN coated compression rings being a very good match with nickel/silicon carbide composite. Anything new in this area.

2) I am not sure there would be any concern with the DLC piston skirt coating and nickel/silicon carbide composite cylinder walls, as under normal operating conditions they should never come in contact. It would be my understanding the the DLC would be concerned with reducing the friction caused by the oil film and/or use of lower viscosity oil in this area. Your opinion?

Brian

xpensive wrote:You want fries with that...Brian?

No, just any knowledge he feels he can make public. This is stuff the average racer has access to these days IF he knows what to ask for.

Scarbs' statement, "uniform over the complete piston", would seem contrary to what I would consider best piston coating practice. IF his statement is accurate, then that means I have to do a little research to see what has changed.

Brian

In hydrodynamically dependent bearings such as this, there will always be an element of boundary-friction where solid-to-solid contact occurs. However, within mechanical process-seals, where the lubricant is a less that one micron thick water-film, we typically run graphite against silicon carbide, why TLC against SiC might not be such a bad idea?

Btw, covering the entire piston with DLC sounds different indeed, it would be interesting to learn more.

They didnt say it was specifically DLC, but it was a black friction reducing coating and was sent out to be coated (i.e. not done at MBHPE). The coating was all over the part, I was told that this was to save the coating contractor having mask the rest of the part in oder to just just coat the skirt.
I saw the rings, I'm no experts but I saw a two sets of ring sper piston. Firstly a pair of thin (stainless steel?) rings with a corrugated inner ring and then secondly a thicker ring, which also appeared to have that black coating on it.

Thanks

I am sympathetic to the masking costs. They would also want to coat the pin bores and ring grooves.

The two rail, corrugate center, ring is the one piece oil ring. They are a work of art. Is anyone have knowledge of how they are made?

I will research "black" friction coatings for something that could be used on the ring cylinder sealing surface/edge and how they might interact with the cylinder coating. You could find the sides of the ring coated with DLC, but I have not heard of that application for the cylinder sealing surface.

Brian

scarbs wrote: Firstly a pair of thin (stainless steel?) rings with a corrugated inner ring ...............

That's how oil collecting rings are usually constructed.

These oil rings are one piece, U shaped. The standard three piece oil ring package, but in on piece. Say 1.5 mm thick and the top ring at .65 mm.

"Dana Corporation has advanced the technology of the engine oil-control ring (OCR) with the
development of a one-piece U-Flex(TM) OCR, an effective alternative to three-
and two-piece OCRs for gasoline and light-duty diesel engines"

Setting the tension would seem the challenge!

Brian