Forged Piston Problems

[Diesel power]

i have used the ceramic coatings on diesel pistons for years andwith the coating not had a heat or nos related issue yet.

where i get my coatings done the ceramic layer is acually part of the piston not just a coating but a chemicl finish.

 

[McRat]

Which coating shop do you use?

 

[Osubeaver]

How thick is the ceramic coating?

 

[Turbo Buick 6]

I believe the problem with anodize is that it expands at a different rate than aluminum does, so for applications of 400 deg or higher, it's not recommended since it can flake. With normal oxidizing, it happens at a microscopic level, so you get some aluminum oxide dust on you when you handle it. When it's heavy anodize, it's different.

Or so I remember.

"Anodized aluminum is easy to clean and resists heat to the temperature at which the aluminum itself melts."

You are probably correct but it is something I am going to look into if I ever have some free time.

 

[Diesel power]

Which coating shop do you use?

Well, i have has a few do the coatings for me but i would only trust two

www.Dartheads.com
www.swaintech.com

 

[Diesel power]

How thick is the ceramic coating?

should only be a few thousands

 

[Osubeaver]

should only be a few thousands

It's interesting that a coating that is only a few thou thick, regardless of how good of an insulator it is can protect a piston.

It seems that anything hot enough to screw your pistons up in an extreme environment would just laugh at the coating and destroy the substrate (aluminum).

It seems it works though, so obviously it does just enough.

Pretty amazing.

 

[Turbo Buick 6]

It's interesting that a coating that is only a few thou thick, regardless of how good of an insulator it is can protect a piston.

It seems that anything hot enough to screw your pistons up in an extreme environment would just laugh at the coating and destroy the substrate (aluminum).

It seems it works though, so obviously it does just enough.

Pretty amazing.

Ceramic is some amazing stuff. They use it in the combustion turbines at work. It was first used in industrial applications so there is no doubt it can work.

 

[mytmousemalibu]

I know this, Top Fuel and Funny Car pistons are iirc phosphate coated! It could be somthin else but think thats what it is. I have one of Kenny Bernstien's pistons up-stairs if some one wants to see the coating. Were loose friends of Hartley Racing which campaign a TF/D and there slugs are coated the same.

Alot of R/C car parts are "Hard-Coated" which is a more durable form of anodizing, this might be somthing to look into?

I wished F1 technology would trickle down to us faster, current 3.0L F1 V-8's are required to run 2 full race events un-touched before a fresh engine can be used, thats including all practice and qualifing and the race itself! And these engines run WOT most the time and RPM about 20,000 revs These motors use full ceramic pistons and cylinders, not coated, full ceramic! And they report in most cases after the 2 races the parts still appear to have no wear! And these engines run super hot with redicoulous piston loads at that kind of RPM, the headers will glow to transparency from reving with no load on them! I WANT THESE FOR THE TRUCK! Cant wait for tech like this for us!

 

[McRat]

The ceramic coating won't stop the piston from igniting, we already tried it and failed. It might be a good thing for other uses, but stopping the reaction from nitrous isn't one.

Anodizing might be the next try.

 

[Osubeaver]

Google

Anodized Piston

Stuff's out there...hmmm

 

[McRat]

Well, some TF use anodized pistons, so whoever told me anodize wasn't OK might be wrong.

 

[Turbo Buick 6]

I swear I had never heard of it befor. Not the first time I came up with an idea on my own that it turned out it was already out there. Makes me wish it was 20 years ago:joker:

 

[Turbo Buick 6]

Looks like they use it mostly on the ring lands as a form of hardening

 

[mytmousemalibu]

Well, some TF use anodized pistons, so whoever told me anodize wasn't OK might be wrong.

Thats kinda what i was gettin at in my above post, it looks like hard coat type of anodizing but not sure if it is or isnt? We'd be hard pressed to find a more harsh enviroment! I wonder if there would be any special consideration for diesels? Especially if burning other elements, nitrous, propane, M/W, CNG?
As is noncompatability or reactivity to fluids or gases eroding the coating?

 

[Fingers]

Hey i dont mind your questions at all, it's those that dont appreciate/listento the answers i give that i would rather not help.


Peak cylinder psi is going to be achieved after ignition which would be after TDC( perfect world)(correctly tuned)

Some engines which are not tuned correctly will have PCP before TDC sadly thats reality.

assuming we are talking about an engine that be injected with nos this is a real word result

peak pressure can NOT happen before TDC. Unless the engine reverses direction.

 

[Fingers]

A quick note on spraying NOx. NOx is itself a FUEL. When you inject the diesel, you light off the NOx charge too. The added benefit is the released O2.

 

[Diesel power]

Thats kinda what i was gettin at in my above post, it looks like hard coat type of anodizing but not sure if it is or isnt? We'd be hard pressed to find a more harsh enviroment! I wonder if there would be any special consideration for diesels? Especially if burning other elements, nitrous, propane, M/W, CNG?
As is noncompatability or reactivity to fluids or gases eroding the coating?

Ceramic phosphate coated pistons are what T/F uses, it should be a green color, and they are chemically bonded to the piston.

 

[Diesel power]

peak pressure can NOT happen before TDC. Unless the engine reverses direction.

Well i think that you can have tremendous pressure before TDC, maybe not peak but enough to slow the rotaion up and cause bent/ broke stuff

 

[Diesel power]

"Piston Coatings
Survival of the fittest also requires a high degree of scuff resistance. Cold starts without adequate lubrication can cause piston scuffing. The same thing can happen if the engine overheats. Piston-to-cylinder clearances close up and the piston scuffs against the bore. The initial start-up of a freshly built engine is also a risky time for scuffing and is of special concern to engine builders because that is when many warranty problems occur.

Applying a permanent low friction coating to the sides of the pistons provides a layer of protection against scuffing. Many engine builders have found that using coated pistons has virtually eliminates warranty problems due to scuffing.

Many late model OEM engines including Ford 4.6L V8, Chrysler 3.2L, 3.5L, 3.8L and 4.0L, and GM 3.1L use pistons with graphite moly-disulfide coatings on the piston skirt to improve scuff resistance. Most aftermarket piston manufacturers also offer some type of coated replacement pistons.

"Thermal barrier" ceramic-metallic coatings for the tops of pistons are another type of coating that have been used on some diesel pistons and performance pistons. Improving heat retention in the combustion chamber improves thermal efficiency and makes more power. It also helps the piston run cooler. But too much heat in the combustion chamber also increases the risk of detonation and preignition, which is not a problem with diesels but is with gasoline engines. So when a coating is used, ignition timing must usually be retarded several degrees to reduce the risk of detonation."