*Always consult your Heat Treater*
      *Information Provided is General*

D-3 is oil hardening high carbon-high chromium die steel developed for purposes where high resistance to wear or abrasion is required. Its size change during heat treatment is outstanding among the non-deforming oil hardening steels; holding size almost as well as the air hardening high carbon-high chromium die steels. D-3 generally is used on specialized applications such as draw dies, forming tools, powder metal tooling and lamination dies, but its application is decreasing due to the development of such steels as D-7 and super high speed steels.

D-3 should be preheated at 1200-1250ºF then transferred to a furnace at 1700-1750ºF. If furnace hardening uses a soak time of 30 minutes for parts over 1 inch or less and add 15 minutes for each inch in thickness over 1 inch.

An interrupted quench is normally advisable, quench in oil until the pieces have lost color and are black (temperature then is about 800ºF. Then remove the pieces from the oil and complete the cooling in still air. Temper the pieces as soon as they have cooled to room temperature.

As soon as the pieces have cooled to room temperature, place the pieces in the tempering furnace at room temperature and raise to the selected tempering temperature slowly. Temper D-3 for a minimum time of 2 hours per inch (25.4mm) of thickness. A tempering temperature in the range of 300 – 500ºF is normally used.

Hardening happens between 1700 – 1750ºF

D-3 is an oversized material, available upon request.


  •  Up to 1″ + .007 up to .0181

  •  1″ up to 6″ + .015 up to .0406

  •  6″ and up + .0625 up to .250

 Hardening Temp.:    1700ºF through 1750ºF

 Quench Medium:  Salt Bath Oil

 Tempering Range:     400ºF through 1000ºF

 Typical Hardness Level: ( 58 – 62 R/C )

 Preheat Forging:   1400ºF through 1500ºF

 Forging Temperature:  2000ºF through 2100ºF

 Anneal Temperature:    1650ºF

 Anneal Cooling Method: Furnace cool to 1000ºF at 100ºF per hr.,  then  air cool.

 Anneal Hardness: 255 BHN

 D-3 Material in Stock

 Color code: SPECIAL ORDER

 Flat Dimensions:

  • 1/8″ x 3 ½” up to 3″ x 3″

  • Non-standard sizes, quoted upon request

 Round Dimensions:

  • 5/8″ up to 10″

  • Non-standard sizes, quoted upon request

 D-3 Typical Analysis:









 · Slight variations from typical analysis shown may occur in order  to maintain the desired graphitizing potential.