Jerry Hey wrote:

Stainless Steel type 253MA which is manufactured by Avesta Polarit and
distributed exclusively by Rolled Alloy in Temperance, Mich., will
withstand continuous operation at 2000 degrees with very little loss do
to scaling.   Its operational range is between 850ºC and 1150º C (2100º
F).  For comparison, type 321 is rated at l700ºF for continuous
operation.

Type 253MA is extremely resistant to loss of scale because the initial
layer of oxide strongly bonds to the the metal (instead of flaking off)
and protects it against further corrosion. When heated to 1150ºC in
cyclic testing (15 minutes at temp/5 minutes at room temp for 1000 hrs
or 3000 cycles) the loss was only 43 mpy.  MPY = mills per year)

  253MA is available in sheet metal but tubing may have to be special
ordered.  I have a call in to Rolled Alloy and I will find out exactly
what thickness of sheet/tube is available and at what price.  253MA is
easily welded and worked similar to other stainless steels.  It work
hardens rapidly.

I have more  information which was faxed to me that is too crappy  to
scan.   Attached is a PDF which presents quite a bit of information on
253 (also 153 and 353 its sister products).       Jerry

The pdf was a bit big Jerry.

Paul Lamar
 
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