What stainless might be in a catalytic oven

They could also be a high nickle alloy or one of the refractory alloys.

"Ignoramus22707" wrote in message news: snipped-for-privacy@giganews.com...

Ignoramus22707 on Thu, 21 Jul

Color might be a result of the heat.

Might be inconel or other high temp alloy.

-- pyotr filipivich "With Age comes Wisdom. Although more often, Age travels alone."

If you send me a small piece, I will ask the guys at the scrap yard to shoot it with their Xrf.

Dan

Dan, Thanks, I might ask you...

The stainless could be 309 or 310. Both are really good for high temperatures. But I am not sure that a catalytic oven would require really high temperature stainless.

Is there a model number or manufacturer's name?

At the scrap yard today I saw a really beat up can of 310 welding rod.

Dan

Complex alloys, including most grades of stainless, can produce oxide colors all over the map, so that is not a guide. As for the likely materials for those grates, that depends entirely on the oven's range of operating temperatures.

Melting temperatures of 302 SS, 310 SS, and Incoloy 800 are within 50 deg. C of each other. Stiffness and yield strength show some wider gaps, but they're still close enough that you won't find your answer just in physical properties.

The selection of which stainless would not be on melting temperature. It would be on resisting corrosion at elevated temperatures.

Dan

Then it depends on what's in the furnace atmosphere when it's in use.

Is there some way to identify inconel without xrf gun, contrasting it with stainless?

Say, if I expose it to a acetylene torch with oxidizing flame, and sprinkle salt on top, would the results be any different with an inconel sample compared to a stainless sample? Any other simple tests that you can think of ?

Do you have a TIG welder? If so, melt a small area but use no argon. If SS then the metal will "sugar". What that means is that the molten metal will swell up and turn black, looking a lot like burnt sugar. I don't know of any other alloys that do that. You might be able to do the same with oxy/acetylene torch.

Here's a picture of the grate:

keep in mind that it spent 20-30 years in a hot fire

This is a SUPER EASY and GREAT idea! Just what I was looking for!

I have a TIG welder no problem...

I assume that inconel would not be sugaring, right?

Was the catalyst part of the deal? There's some chance it's worth more than the metal in the oven. TiO2 isn't very valuable, but if it's just a support for something else, like platinum or palladium....

bob prohaska

Yes, but they kept TiO2...

Ignoramus3825 fired this volley in news: snipped-for-privacy@giganews.com:

Again, Ig, you should call those "the catalyst pellets", and not "TiO2".

They _may_ have a titanium dioxide SUBSTRATE (usually it's alumina [Al2O3], shrug), but that's not the catalyst.

As Bob correctly said, sintered oxide pellet is nothing but an INERT solid that can withstand high temperatures. Usually a rather thin layer of a catalytic metal is vapor-deposited on the outsides of the pellets.

Lloyd

TiO2 has some catalytic activity by itself:

I didn't see any mention of it for destroying toxic wastes that might have contaminated the metal grating, but Google wouldn't reveal a proprietary process.

--jsw

Lloyd, I had no idea, thanks for shedding light on this.

"Jim Wilkins" fired this volley in news:nn2eoh$vu6$ snipped-for-privacy@dont-email.me:

Jim, you might want to think of the practicality of that in terms of a mass of the pellets residing in a stack filter full of smokey exhausts!

For all practical purposes, TiO2 is not anything but a refractory substrate.

LLoyd