Thermal spray and fuse forming (Wire Combustion type)

I have many projects that I could use such a beast for, not the least of which is EDM electrode forming, possibly free-standing thin-walled components as well. My question is, is it possible to ATTAIN the WROUGHT PROPERTIES of the sprayed material with adequate fusing (and possibly fluxing) of the sprayed coating? System would be a Metco 10E with oxy/acetylene, and an oxy/acetylene torch for fusing. Spray-formed components approx. 2mm max thickness. Components would be fairly small, like 6"x12" area, I don't care if I have to stand there with a torch for 2 hours (it would still be saving me countless hours of headaches and costly labor), I just want to know if it can be done with that equipment, and what fluxes, shielding gases etc. I would need, if any. The key is to attain the wrought properties, ie ~ ELIMINATE ~ (at least to a VERY low value) oxide inclusions, porosity, and stresses. Thanks!

General G

Reply to
Nathanael
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Sounds like you'd need an inert gas glovebox or a vacuum furnace to meet your purity requirements.

Gary

Reply to
Gary Coffman

Electroforming is what you want. You use wax with a conductive coating or a low melting-point alloy for backing and melt it out afterwards. Slower than a couple of hours, though. Used for small intricate pieces, not really a production technique. Any decent technical library will have something on the subject.

Stan

Reply to
Stan Schaefer

------------ Radar wave guides and bellows coupling are mass-produced by electro forming to great accuracy. Don Warner

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Reply to
Donald

Thanks for the replies, but I am familiar with electroforming, and it's not what I need. I could deal with the extensive lead-times on the electro process, but it's the material selection that stops me. Electroforming is only for a select few metals, copper, silver, chromium, gold, nickel, etc. I am doing parts of 4140, 1018, etc. Even if I could have plating baths specially mixed for those (expen$ive), I would still have to deal with hydrogen embrittlement, haz waste, and a host of other headaches. What kind of density values could be attained practically with the thermal spray process? Similar or better % of theoretical density than hot-cast?

Nathanael

Reply to
Nathanael

Worse. Metal spraying produces a porous coating because the molecules individually freeze to the substrate as they are sprayed. You get voids from entrained air unless you do the spraying in a vacuum. You'd need to add pressure to get it to approach the same density as a liquid metal casting. Or you'd have to heat the underlying substrate sufficiently to allow the sprayed metal to transition to a sensible thickness liquid coating before freezing in place, ie like spray transfer MIG welding.

Gary

Reply to
Gary Coffman

Just to clarify, I am talking about spray and FUSE coatings. The fusing process is done by either putting the part in a furnace or just going over it with an acetylene torch. I know extremely low porosity is attained with this method, but I need to know HOW low. I need something 98% theoretical density or better. Thanks

Nathanael

Reply to
Nathanael

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