Sintering process for nickel wire mesh - Eng-Tips

I work at a commercial heat treater with vacuum furnace equipment. We had a local manufacturer contact us to ask if we could sinter together nickel wire mesh sheets (product as described in this paper).

The manufacturer's current supplier sinters stainless steel sheets for him, but they have a customer requesting mesh made of nickel alloy 200, and their current supplier will not work with that material.

We have no experience with sintering wire mesh. The manufacturer also had no idea what the sintering process would look like. Does anyone know of any references with general information on times, temperature, and atmosphere requirements for this kind of sintering? Find vendors capable of making AMS Alloy Sheet and Strip, Sintered Wire Mesh, Corrosion and Heat Resistant 30Fe - 1.5Mn - 21Cr - 20Ni - 20Co - 3.0Mo - 2.5W - 1.0(Cb + Ta) - 0.15N Porous - UNS R

Regards, Wil Taylor

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We used to sinter Ni200 mesh.
First the mesh must be rolled flat.
Then you stack layers of them onto a very solid base plate (coated with Al2O3 to prevent sticking).
Then you set a heavy flat steel plate on the top to hole them all in contact.
We always sintered in hydrogen with a dew point -80F.
Then after we sintered them we would cold roll it in order to get the density that we wanted.

This is just as easy as sintering stainless, not sure why the current guys wouldn't do it.

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P.E. Metallurgy, Plymouth Tube Hi Ed - Thank you for the process description, it looks like we would need some specialized fixturing if this customer wanted to work with us, and they would need to do any rolling themselves. Our vacuum furnaces usually run around 50 microns of pressure, which is roughly equivalent to hydrogen with a dew point of -60; not quite as dry as your process, but perhaps close enough to work.

Would you be willing to share what times and temperatures you used? I think that you would need some Hydrogen at the beginning of the cycle in order to strip surface oxides.
After that Vac should work, but I not sure if 50u is low enough.
The fixtures were just steel plates that were ground flat. We used the lowest C steel that we could find.
I don't remember the temp exactly. We were doing it in a continuous furnace. We heated high in the first zone (F?) then dropped to a lower temp (F?). The total time was 30-60 min. We were trying to limit grain growth.
You should double check the vapor pressure of Ni. You want to vaporize a little (it helps it stick together when it condenses) but you don't want to boil off too much.


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P.E. Metallurgy, Plymouth Tube

now that i see what your talking about weld mesh would,nt be for the job. wire it is. looks like 6mm from here. so stainless or mild. stainless wire is a w###e to bend, unless you get into heating the stuff (lots of money and time), its springy. i,d go with mild and then powder coat if you can get the right price. nice little job for your new tig. get bright wire for your tig, so its heitons again. you'll have to make up a tool to pull the wire around.

Hurly, a mind boggling game, how in hell do you catch a ball on the end of a stick and run along with it? And how have any of the players still got their heads still atached with that stick being swung about at head height? Bonkers stuff. But great to watch.
I reckon 6mm bar, and good welds.
Chunko.

if they still had their heads at the end of the game it wasn't my fault 30 blokes in a small field with three foot sticks who'd be a referee

now that i see what your talking about weld mesh would,nt be for the job. wire it is. looks like 6mm from here. so stainless or mild. stainless wire is a w###e to bend, unless you get into heating the stuff (lots of money and time), its springy. i,d go with mild and then powder coat if you can get the right price. nice little job for your new tig. get bright wire for your tig, so its heitons again. you'll have to make up a tool to pull the wire around.

That could be a problem with stainless steel it shouldnt be to hard to make up some sort of jig for bending the wire I must get a helmet with a face guard to see if I can figure out what they are made of
and some work for the new tig I presume the bright wire is for filler