Nimonic 90 Equivalent Materials

Possibly an Inconel alloy or possibly another iteration of the Nimonic family say 75 or 80a....?

https://www.quora.com/What-is-the-difference-between-Nimonic-and-Inconel-alloys

https://en.wikipedia.org/wiki/Nimonic

I will look more into Inconel. Thank you for the suggestion

More information on operating environment (gas turbine, maybe?) would help.

What does the part do?

Have you considered electrical discharge machining?

It is a seat assembly (upper and lower piece) with a carbide tungsten ball in the center that acts as a sealer that is apart of a aircraft valve (hence the high temperature, wear resistance and high pressure).

EDM is not possible for some of the operations required to machine it (I determined that through drawing interpretation)

My main problem is finding a machine shop capable of machining nimonic 90. Maybe I research more machine shops and try posting somewhere else.

What makes you say that EDM is not possible for some of the operations? We regularly use both wire and plunge EDM to machine Inconel, Hastelloy, and other similar "superalloys".

I think you should listen to lyn and dkwarner. Find a shop proficient in EDM machining...a shop that regularly does EDM machining of various types.

EDM is not usually limited by ability to produce parts that other standard types of machining (milling machine, lathe, broach, etc) can produce. EDM is very capable in what can be removed where. The limitation of EDM is typically time and cost due to time.

You are likely incorrect in your assessment of EDM ability to machine your part if you believe other stabdard processes can complete the job.

These guys might have some suggestions....

https://www.ves-precision.com/

...but to nail anything down we would need to know the function, environment and design life, any budget restrictions and other pertinent details....

If you can equate the use to that of engine valves, then perhaps that might lead to some possibilities....

..."On some passenger car and light truck engines, the original equipment intake valves are 1541 carbon steel with manganese added to improve corrosion resistance. For higher heat applications, a 8440 alloy may be used that contains chromium to add high temperature strength. For many late model engines (and performance engines), the intake valves are made of an alloy called “Silchrome 1” (Sil 1) that contains 8.5 percent chromium."...

https://www.enginebuildermag.com/2005/12/valve-selection-hot-valve-materials-for-hot-engines/

Thanks for the suggestions. I am going to look more into the carbon steel alloys

This sounds like an impossible quest. You need really tough material, immune to surface wear that is also easy to machine. Unless you can machine soft material and then harden it or coat the soft material with a hard finish after machining (ceramics comes to my mind) this sounds like an impossible quest.

Not sure why this was voted OT.

If I were the OP, I'd do a thorough search for machine shops.

Super Alloy Nimonic 90 ™ (UNS N07090) https://www.azom.com/article.aspx?ArticleID=7760 Nimonic 90 ™ can be machined using conventional methods which are used for iron-based alloys. Machining operations are performed usingNimonic 90 ™ is welded using shielded metal-arc welding, gas-tungsten arc welding, gas metal-arc welding, and submerged-arc welding methods.

In my post I mention that it has been difficult to find a shop capable of machining nimonic 90, Hence why I'm looking for other material options. The piece itself is not a hard part to make from a manufacturing standpoint, it's just the material.

Thank you for the responses though, everything helps!

Okay, well it would help to know what attribute(s) of the superalloy, nimonic 90, are relevant for anyone to suggest a replacement material.

I still think an alumina ceramic might meet your concerns if abrasion and thermal expansion are your only concerns. A polished glaze on bearing surfaces could also reduce friction. Impacts might crack things but nobody mentioned anything about impacts.

Where I work we use UHV vacuum chambers and magnetic containment to isolate and steer very hot material to nanometer accuracies but you're obviously not manipulating electron beams.

In the past I have been faced with a similar dilemma. Ended up making the part from a carbon steel then having Nimonic deposited just on the seal area by using a Nimonic arc welding rod. This was then finished by grinding.

Someone else suggested looking at carbon steel as well which is what I am researching currently. Thank you!

I rather think that it will be the very property of wear resistance that will make machining difficult.

Electric Discharge Machining works on fully hardened tool steels and other hard conductive materials.

Thanks for your comments everyone, I believe I have what I need.

BT