Plausible Idea?- Titanium Nitride coated crank, rods, valves, etc

Hi, first time poster on this group.... thought i'd stray away from some of the other groups/forums/boards and a general audience.

Would it be a plausible idea to have a hard coating done on various engine internals? If you didn't know, Titanium Nitride is that golden film stuff you see on drill bits..... The stuff puts an insane hard coat, reducing friction, wear, making stuff more heat resistant, etc. Well, I've had this idea lingering in my mind, and I'm not the only one, but I haven't seen it done.... although one website on the internet sells TiN coated valves. The coating isn't thick at all.... it is thin to about .0003", and is known to make mill/lathe/machining bits last 10times or so longer.

.....So...... Do you guys see any faults with this concept? Surely pistons can be ceramically coated so heat energy doesn't transfer as easily, thus less energy wasted..... so could I coat my pistons with TiN? And the crankshaft, rods, valves, and anyother thing? What I plan to do it do some crank knifing, taking off factory imperfections etc, then hard coating them for strength and possible performance gains (because of less friction, different heat transfer, etc).

Thanks

Reply to
PedGuyKev
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I do not know which Nitride is used but some high performance crankshafts have had their journals Nitrided (surface hardened) for many years. Stan

Reply to
Stan Weiss

Reply to
Shep

It isn't a matter of using a certain "nitride". Nitrogen, adsorbed at the surface, forms a hard Iron Nitride right at the surface. This is underlain by a softer gradient layer that contains diffused nitrogen. The surface is the hardest but the diffused layer provides most of the benefit for crank endurance.

Reply to
cavedweller

----Original Poster

The only reason was his golden film. Which I did not remember the last time I had a nitride crankshaft. Stan

Reply to
Stan Weiss

The first question that comes to mind is I'm not clear what you want to accomplish by coating engine parts with that material. Simply placing a very hard coating on parts may introduce it's own set of problems. Extreme hardness in materials can also bring with it a tendency to shatter and chip. Does that occur with a Titanium Nitride surface?

Also, how does that material react to material used in bearings.

Once the energy in gasoline has been converted to another form and used the excess remains as heat and is of little use once the engine reaches operating temperature. Why would you want to trap heat in pistons and other metal surfaces (assuming this mircale material can do anything like that).

You are making a statement that it reduces friction. How is that done.

Reply to
John S.

PedGuyKev wrote: The coating isn't thick at all.... it

Another poster mentioned the hemi cranks from the sixties. I do know that a lot of industrial manufacturers made hard crankshafts in the sixties, although I'm not sure of the process or the materials that they used.

The main problem with hardening a crankshaft is when you want to rebuild the motor and you have to turn the crankshaft. When you would undersize the crank you would take away the hardness. A lot of manufacturers did not recommend this, I guess maybe because they wanted you to buy their new crankshaft.

If MONEY WAS NO OBJECT, I'd like to see somebody build something like a titanium crankshaft and test it. Would it work for super high RPMs? I'm not sure because there probably has to be a small but certain amount of flexibility in a crankshaft. Food for thought.....

Reply to
Kruse

If you read the other post here you will see nitride on crankshafts has been used for many years .

How do you get heat trapped in pistons from

----Original Poster

In racing engines pistons and combustion chambers along with valves and sometime the ports in the heads have a heat barrier installed. This results in increased HP. Stan

Reply to
Stan Weiss

Silly me not to have perceived that from your post. :-s

Reply to
cavedweller

As you said cutting the crankshaft removed the hardened surface and at that time (do not know about today) there was no place to get one renitride. I used to get them hard chromed and if they did not need to be cut to much could get them back to standard this way.

If you do a web search I think you will find this has been done in a very high end race engine. The more common thing is titanium connecting rods. Stan

Reply to
Stan Weiss

I have no idea. I was guessing at what the O.P was trying to say.

Reply to
John S.

OE engine folks usually "premiumed" forged crankshafts by adding journal and journal fillet induction hardening before finishing.

Not clear to me why an engine rebuild would require turning a crank. I would think removing journal material to say, .030" u/s , would be done by grinding. Grinding can handle a hardened journal quite nicely and the hardened depth remaining is still adequate.

Flexibility? All metals are elastic to varying degrees.

Reply to
cavedweller

For me it was racing and a spin bearing. At the time the nitride was suppose be only a couple of thousands deep / surface hardened.

Reply to
Stan Weiss

You mean a "spun" bearing?

Well, nothing's changed. Nitriding is still only a couple of thousandths deep. The compound layer on the surface is in the order of tenths, the diffused layer is "sort of" a couple thou. If you grind a journal to clean it up morfe than that, the nitriding is gone. So what? The real benefit from nitriding is in the journal fillets, where the fatigue cracks usually start.

Leave the fillet alone and you're good.

Reply to
cavedweller

How I plan on adding performance:

  1. Removing those imperfections and what not, and knifing the rods.
  2. Knifing Crank
3.Lightening pistons
  1. Milling the tops of pistons

Titanium nitride comes into play in these ways (theoretically), 1-4 respectively:

  1. Removing material from these things is compensated for strength by the TiN coat. Heat isn't absorbed into the part as much because of the coating. Surface means it has less friction so oil can glide across it, and it will spin freerer. Less expansion from heat.
  2. Same as reason above.
  3. Pistons have always been ceramically coated on top for heat transfer purposes. Proven increase in performance, so why not use a TiN coating which has a similar qualitiy? Won't expand as much.
  4. Same as 3.

Now they do sell valves with TiN coat, so I'm throwing that into the mix, as well as other things as I can think of.

Also, it is cheaper to have a whole part coated than just a small section (so the person won't have to mask parts off). I asked around, and the prices are relatively cheap, it's just that the minimum order is at least $300ish, which I'm sure covers most of the expense. Thanks for the input so far guys.

Reply to
PedGuyKev

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