Stainless steel for my wood stove

[37 chief]

The original metal on my antique wood stove was starting to have some burn through areas. I bought a piece of stainless steel, had it rolled to fit the
inside of my stove. After 15 or more years it is starting to burn through also. It was probably a poor grade of stainless I picked at the scrap yard. What grade
of stainless sheet metal is rated the best for high heat. Wish I knew the grade of sheet metal that was used when the stove was made. It has lasted for over 100
years. Stan

 

[drsportster]

309 has highest temp at 2000 310 a close second .

 

[Janicholson]

Stainless steel is not recommended for stoves. Medium 40 point carbon steel is better by far. Look at modern wood stoves for sale. they are not stainless. Stainless steel is high in chrome. It has high strength in heat, but does not transfer heat well. The chrome is also able to be affected by caustic ash and other residue in a wood or coal flame. Medium carbon steel is much less expensive, has much better thermal transmission, and will last well. It also can be rolled and cut for doors/windows better. Jim
From New Way Stove company

 

[IaLeo]

Can't recommend a metal, just want to say, those stove fires are sure pleasant on a cold evening (or day) aren't they.

 

[stevieb49829]

Stan, how did my son's cat get to California while I wasn't looking?? He was just here a minute ago. steve

 

[kcm.MN]

If you're going to use stainless in a wood stove, then it needs to have ceramic or other masonry product in front of the metal. As mentioned, stainless doesn't like places like the inside of a wood stove. A metal high in carbon would be a better choice. Look at how long cast iron lasted in old wood stoves such as yours. Not sure of the chemical makeup of that cast iron, but it will last far longer than any stainless out there.

 

[37 chief]

The cat heard the mice were bigger in California, and hopped on the nest plane. Stan

 

[Janicholson]

4.5 to 6.5% carbon!! 450 points to 650 points High carbon steel has 60 to 125 points. Jim

 

[HFJ]

i just have average sized mice here in michigan, but my two boys were busy and rounded up 3 of them in the last 24 hours. i hope that just means winter is coming, and not that they already have a colony in here somewhere.

 

[MarkB_MI]

316 stainless has the best corrosion resistance of the commonly available alloys. Most likely your current patch is 304, which is pretty good but not quite as good as 316. I don't know about their use inside stoves, but chimney liners are available in either grade; 316 stainless chimney liners are used for coal stove chimneys, while either grade is fine for wood stoves.
304 vs 316 corrosion resistance

 

[Geo-TH,In]

Stan,

Here is a table of thermal conductivity.

Stainless steel is more like an insulator.

You may want to repair your wood stove with iron or buy a new one.

Using stainless steel means you could be sending about 3x more heat up the chimney.

 

[kcm.MN]

(quoted from post at 21:15:12 09/09/23) 4.5 to 6.5% carbon!! 450 points to 650 points High carbon steel has 60 to 125 points. Jim

Low carbon, eh? Guess it's a good thing I don't make wood stoves. *lol*

Thank you, Jim, for the correction!!

 

[Russ from MN]

I wondered about stainless being a poor conductor of heat, I was pretty sure it was pretty poor, it also has more thermal expansion, so it would move around in the stove.

 

[Loosehandle]

He can't wait for that thing to be lit

 

[Stephen Newell]

The only thing I'm wondering is if the burn through places will emit smoke.

 

[Dave G9N]

(quoted from post at 06:29:34 09/10/23) I wondered about stainless being a poor conductor of heat, I was pretty sure it was pretty poor, it also has more thermal expansion, so it would move around in the stove.

tainless steel can be either straight chrome (400 series) or chrome nickel (300 series). There are some other categories, but they are more expensive and less available. The straight chrome grades have slightly lower thermal expansion than carbon steels and the thermal conductivity is a little better than CrNi and lower than carbon steels.

409 stainless is used for exhaust systems. It has only 11% Cr and it will rust some, so it isn't decorative, but it does last in exhaust systems. Any polished stainless will have low emissivity, but 409 won't stay pretty. As for conductivity, I can see where it would make more of a difference in a thick section, but for sheet, I have my doubts. Doubts and facts are not always closely related.

A good high temperature coating like the ones used for exhaust manifolds should protect the metal and increase thermal radiation. It should help with either plain carbon or 409 stainless steel.

The only reason I can think of for medium carbon vs low or high carbon steel is that the thermal conductivity around 0.5% C is slightly higher than the higher or lower carbon grades. It may be the peak of a rounded curve, but not that much different from lower and higher carbon plain carbon steel. Whatever you can get locally should suffice. I wouldn't be surprised to find that any plain carbon steel will eventually settle out at about the same carbon content. An oxidizing flame will remove carbon and a reducing flame will increase it. It may eventually depend on the temperature and atmosphere inside the stove.

 

[jimhorne]

For high heat, the best grade of stainless steel sheet metal is typically 304 or 316 stainless steel. These grades are resistant to corrosion and can withstand the intense heat of a wood stove. It sounds like the american made steel you used may have been of lower quality, hence why it's starting to burn through after 15 years. It's tough not knowing the exact grade used in your antique stove, but opting for 304 or 316 stainless steel fabricated parts should provide better longevity and heat resistance for your wood stove.