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Heat Treat Foil - Stainless Steel 321 / 309

  • Foil tool wrap
  • Heat treat foil
  • Tool Wrap Stainless Steel Foil
Click to enlarge

The use of stainless steel foil to reduce decarburization of air hardening tool steel is a common practice for tool room shops. How to use it: form a pouch or pocket and fold the edges several times (triplefold) over. Be carefull, the edges of the stainless steel tool wrap are very sharp! Tips:
1. A small piece of paper in the pocket (that will burn up at 1000degF) will consum most of the trapped oxygen.

Keith stocks rolls of stainless steel heat-treating foil with .002" thickness and 24" Wide 
  • Alloy #321 is a high-titanium, soft annealed stainless intended for heat treating parts at temperatures up to 2000F.
    • Due tu supplier issues unavailable until further notice
  • Alloy #309 may be used at temperatures up to 2240F.

Stainless Steel Foil Roll Sizes and Packaging

  • Alloy #321(not available at this time) & #309 foil is available in 24" wide by 100 ft long (200 sq ft) rolls packed in convenient dispenser cartons, 
  • Special widths and lengths of foil are also available by special order.

Stainless steel foil tool wrap protects air-hardening tool steel parts from scale and oxide buildup during heat treating in ordinary furnaces. By using foil tool wrap in your conventional furnace, one realizes nearly the same benefits of vacuum or controlled atmosphere furnaces but at a fraction of the cost.

Heat Treating Foil
Foil may be cut, folded and creased easily to create a protective airtight envelope around parts that will not tear easily during normal use. Our high quality foil is produced by mills here in the U.S. to exacting metallurgical standards and with a very uniform thickness. The foil is resistant to chromium carbide precipitation during exposure to high temperatures. Decarburization buildup is also eliminated.


  • Typically used in heat-treating applications to reduce scale and discoloration of parts
  • Protects parts from oxide build up
  • No special controlled atmospheric furnaces are required
  • Protects the surface of heat treated parts

Stainless Steel Foil
 Stainless Steel Heat Treat Foil is an annealed stainless steel used in the heat treating of tool steel parts. The wrap eliminates the need for Ni-Chrome, box packing and the use of sawdust or other carbonaceous materials. No special controlled atmosphere furnaces are required to use the foil.

Keith Heat Treat Foil is guaranteed to be taken up to temperature.

  • #321 Stainless guaranteed to 2000° Fahrenheit
  • #309 Stainless guaranteed to 2240° Fahrenheit

Obtaining the protection for air-hardened tool steel parts at the temperature you need is a simple task at hand; Keith Stainless Steel Heat Teat Foil is easy to use:

  • Place tool In Foil.
  • Fold over and crimp edges to form an air-tight package.
  • Place package in oven and heat treat in usual way.

Further technical information is available upon request.