ASTM A681-08 pdf free.Standard Specification for Tool Steels Alloy.
ASTM A681 covers the chemical, mechanical, and physical requirements for available wrought alloy tool steel products.
3. Classification
3.1 Material in accordance with this specification is classifled by chemical composition. Types correspond to respective AISI designations.
3. 1 . I 1-lot Work Tool Steels, Identification H:
3.1.1.1 Types H1O to H 19 are characterized by a controlled chroniium content along with other alloying elements. The first four, containing molybdenum, offer excellent toughness and high hardenability and are frequently used in cold work applications requiring toughness at relatively high hardness levels.
3.1.1.2 Types H21 to H26 are characterized by a controlled tungsten content along with other alloying elements. These steels oiler greater resistance to the softening effect of elevated service temperatures but exhibit a lower degree of toughness.
3.1.1.3 Types H41 to H43 are low-carbon modifications of molybdenum high speed tool steels (Note 1) and have characteristics similar to the tungsten types.
3.1.2 Cold Work Tool Steels, Identification A—Types A2 to AlO cover a wide range of carbon and alloy contents but all have high hardenahility and may be hardened in air. The low carbon Types A8 and A9 have less wear resistance but offer greater toughness than others in this group. Type A7, with high carbon and vanadium, offers exceptional wear resistance but at a very low level of toughness.
5. Materials and Manufacture
5.1 Unless otherwise specified, material covered by this specification shall be made by an electric melting process. It shall be made from ingots or slabs that have been reduced in cross section in such a manner and to such a degree as to ensure proper refinement of the solidification structure.
6. Chemical Composition
6.1 An analysis of each heat of steel shall be made by the manufacturer to determine the percentage of the elements specified, and these values shall conform to the requirements for chemical composition specified in Table 1. If requested or required, the chemical composition shall be reported to the purchaser or his representative.ASTM A681-08 pdf download.