1、Designation: A681 08 (Reapproved 2015)Standard Specification forTool Steels Alloy1This standard is issued under the fixed designation A681; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This specification covers the chemical, mechanical, andphysical
3、 requirements for available wrought alloy tool steelproducts.1.2 These products, which include hot or cold finished bar,plate, sheet, strip, rod, wire, or forgings, are normally fabri-cated into tools, dies, or fixtures. The selection of a material fora particular application will depend upon design
4、, serviceconditions, and desired properties.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards
5、:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA561 Practice for Macroetch Testing of Tool Steel BarsA600 Specification for Tool Steel High SpeedA700 Guide for Packaging, Marking, and Loading Methodsfor Steel Products for ShipmentE3 Guide for Preparation of Metallographic
6、 SpecimensE30 Test Methods for Chemical Analysis of Steel, Cast Iron,Open-Hearth Iron, and Wrought Iron (Withdrawn 1995)3E45 Test Methods for Determining the Inclusion Content ofSteelE59 Practice for Sampling Steel and Iron for Determinationof Chemical Composition (Withdrawn 1996)3E527 Practice for
7、Numbering Metals and Alloys in theUnified Numbering System (UNS)2.2 Military Standard:4MIL-STD-163 Steel Mill Products, Preparation for Ship-ment and Storage2.3 Federal Standards:4Fed. Std. No. 123 Marking and Shipment (Civil Agencies)Fed. Std. No. 183 Continuous Identification Marking of Ironand St
8、eel Products2.4 Other Standards:5SAE J1086 Recommended Practice for Numbering Metalsand Alloys (UNS)3. Classification3.1 Material in accordance with this specification is classi-fied by chemical composition. Types correspond to respectiveAISI designations.3.1.1 Hot Work Tool Steels, Identification H
9、:3.1.1.1 Types H10 to H19 are characterized by a controlledchromium content along with other alloying elements. The firstfour, containing molybdenum, offer excellent toughness andhigh hardenability and are frequently used in cold workapplications requiring toughness at relatively high hardnesslevels
10、.3.1.1.2 Types H21 to H26 are characterized by a controlledtungsten content along with other alloying elements. Thesesteels offer greater resistance to the softening effect of elevatedservice temperatures but exhibit a lower degree of toughness.3.1.1.3 Types H41 to H43 are low-carbon modifications o
11、fmolybdenum high speed tool steels (Note 1) and have charac-teristics similar to the tungsten types.NOTE 1High-speed tool steels are covered in Specification A600.3.1.2 Cold Work Tool Steels, Identification ATypes A2 toA10 cover a wide range of carbon and alloy contents but allhave high hardenabilit
12、y and may be hardened in air. The lowcarbon Types A8 and A9 have less wear resistance but offergreater toughness than others in this group. Type A7, with high1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloysand is the direct responsibilit
13、y of SubcommitteeA01.29 on Tool Steels.Current edition approved Sept. 1, 2015. Published September 2015. Originallyapproved in 1973. Last previous edition approved in 2008 as A681 08. DOI:10.1520/A0681-08R15.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custome
14、r Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from DLA Document Services, Building 4/D, 700 Robbins Ave.
15、,Philadelphia, PA 19111-5094, http:/quicksearch.dla.mil.5Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale,PA 15096, http:/www.sae.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1carbon and vanadium, offers
16、exceptional wear resistance but ata very low level of toughness.3.1.3 Cold Work Tool Steels, Identification DTypes D2 toD7 are characterized by high carbon and high chromiumcontents and exhibit high resistance to abrasion. The typescontaining molybdenum may be hardened in air and offer ahigh degree
17、of dimensional stability in heat treatment.3.1.4 Cold Work Tool Steels, Identification OTypes O1 toO7 are low-alloy types that must be hardened by quenching inoil. Sizes over about 2 in. (50 mm) in cross section usuallyexhibit lower interior hardness.3.1.5 Shock-Resisting Steels, Identification STyp
18、es S1 toS7 vary in alloy content but are intended for shock-resistingapplications.3.1.6 Special-Purpose Tool Steels, Identification LTypesL2 to L6 are low-alloy steels with a wide range of carboncontent. The low-carbon types are generally used for structuralapplications requiring good levels of toug
19、hness, while thehigh-carbon types may be used for short-run tools.3.1.7 Special-Purpose Tool Steels, Identification FTypesF1 to F2 are high-carbon steels with varying tungsten contentused primarily for relatively short-run fine edge cutting tools.3.1.8 Mold Steels, Identification P:3.1.8.1 Types P2
20、to P6 are very low-carbon steels and mustbe carburized after machining or hubbing.3.1.8.2 Types P20 and P21 are usually supplied in theprehardened condition and can be placed in service directlyafter machining.4. Ordering Information4.1 Orders for material under this specification shall includethe f
21、ollowing information, as required to describe adequatelythe desired material:4.1.1 Class of material (hot work tool steel, etc.),4.1.2 Type (H11, D2, etc.),4.1.3 Shape (sheet, strip, plate, flat bar, round bar, squarebar, hexagon bar, octagon, special shapes),4.1.4 Dimensions (thickness, width, diam
22、eter, length),4.1.5 Finish (hot rolled, forged, blasted or pickled, colddrawn, machined, ground, precision ground and polished),4.1.6 Condition (annealed, hardened and tempered, etc.),4.1.7 ASTM designation and year of issue, and4.1.8 Special requirements.5. Materials and Manufacture5.1 Unless other
23、wise specified, material covered by thisspecification shall be made by an electric melting process. Itshall be made from ingots or slabs that have been reduced incross section in such a manner and to such a degree as to ensureproper refinement of the solidification structure.6. Chemical Composition6
24、.1 An analysis of each heat of steel shall be made by themanufacturer to determine the percentage of the elementsspecified, and these values shall conform to the requirementsfor chemical composition specified in Table 1. If requested orrequired, the chemical composition shall be reported to thepurch
25、aser or his representative.6.2 Analysis may be made by the purchaser from finishedbars and forgings by machining off the entire cross section anddrilling parallel to the axis of the bar or forging at any pointmidway between the center and surface in accordance with thelatest issue of Practice E59. T
26、he chemical analysis of thedrilling chips shall be made in accordance with the latest issueof Test Methods E30. The chemical composition thus deter-mined shall not vary from the limits specified in Table 1.7. Hardness Requirements7.1 Annealed hardness values shall be obtained in accor-dance with the
27、 latest issue of Test Methods and DefinitionsA370, and shall not exceed the Brinell hardness values (orequivalent Rockwell hardness values) specified in Table 2.7.2 Specimens for determination of minimum response tohardening shall be14-in. (6.4-mm) thick disks cut so as torepresent either the full c
28、ross-sectional area or that midwaybetween the center and outer surface of the material. If thematerial form or size does not lend itself to accurate hardnessdetermination on14-in. thick cross-sectional disks, then longi-tudinal specimens may be used for hardness testing. Examplesare round bars less
29、than12 in. (12.7 mm) in diameter or sheet.In this case, the specimen shall be a minimum of 3 in. (76 mm)in length and parallel flats shall be ground on the original millsurfaces. The specimens shall be heat treated as prescribed inTable 3.7.2.1 The hardness of the specimen after the specified heattr
30、eatment shall meet the minimum hardness value for theparticular type of steel shown in Table 3. Rockwell C testsshould be used where possible but light load tests may benecessary on thin specimens. These tests should be specified byagreement between the seller and the purchaser. The hardnessvalue sh
31、all be obtained in accordance with the latest issue ofTest Methods and Definitions A370, and shall be the average ofat least five readings taken in an area midway between thecenter and surface of the largest dimension of the cross-sectional specimen or along the parallel surfaces of thelongitudinal
32、specimen.8. Macrostructure8.1 Specimens for the determination of the macrostructureshall represent the entire cross-sectional area in the annealedcondition and be prepared in accordance with the latest issue ofPractice A561. Material supplied to this specification shall becapable of exhibiting a str
33、ucture free of excessive porosity,segregation, slag, dirt or other nonmetallic inclusions, pipe,checks, cracks, and other injurious defects.8.2 Macroetch severity levels for center porosity and ingotpattern, illustrated photographically in Practice A561, shall notexceed the ratings specification in
34、Table 4 for the appropriatematerial size and composition. More stringent requirements areavailable by agreement between seller and purchaser.9. Decarburization9.1 Specimens for the determination of decarburizationshall represent a cross section of the material and be preparedin accordance with the l
35、atest issue of Guide E3. Materialsupplied to this specification shall be capable, when examinedA681 08 (2015)2at 20 times or greater magnification, of not exceeding thevalues given in Tables 5-8 for the appropriate size and shape ofmaterial. Lower limits of decarburization may be specified byagreeme
36、nt between the seller and purchaser.9.2 Material ordered as ground and polished or groundfinished or machine finished shall be free of scale anddecarburization.TABLE 1 Chemical Requirements, %AUNSDesig-nationBTypeCarbon ManganeseCPhos-phorus,maxSulfur,DmaxSilicon Chromium Vanadium Tungsten Molybdenu
37、mmin max min max min max min max min max min max min maxT20810 H10 0.35 0.45 0.20 0.70 0.030 0.030 0.80 1.25 3.00 3.75 0.25 0.75 . . . . . . 2.00 3.00T20811 H11 0.33 0.43 0.20 0.60 0.030 0.030 0.80 1.25 4.75 5.50 0.30 0.60 . . . . . . 1.10 1.60T20812 H12 0.30 0.40 0.20 0.60 0.030 0.030 0.80 1.25 4.7
38、5 5.50 0.20 0.50 1.00 1.70 1.25 1.75T20813 H13 0.32 0.45 0.20 0.60 0.030 0.030 0.80 1.25 4.75 5.50 0.80 1.20 . . . . . . 1.10 1.75T20814 H14 0.35 0.45 0.20 0.60 0.030 0.030 0.80 1.25 4.75 5.50 . . . . . . 4.00 5.25 . . . . . .T20819 H19 0.32 0.45 0.20 0.50 0.030 0.030 0.15 0.50 4.00 4.75 1.75 2.20 3
39、.75 4.50 0.30 0.55 Co 4.004.50T20821 H21 0.26 0.36 0.15 0.40 0.030 0.030 0.15 0.50 3.00 3.75 0.30 0.60 8.50 10.00 . . . . . .T20822 H22 0.30 0.40 0.15 0.40 0.030 0.030 0.15 0.40 1.75 3.75 0.25 0.50 10.00 11.75 . . . . . .T20823 H23 0.25 0.35 0.15 0.40 0.030 0.030 0.15 0.60 11.00 12.75 0.75 1.25 11.0
40、0 12.75 . . . . . .T20824 H24 0.42 0.53 0.15 0.40 0.030 0.030 0.15 0.40 2.50 3.50 0.40 0.60 14.00 16.00 . . . . . .T20825 H25 0.22 0.32 0.15 0.40 0.030 0.030 0.15 0.40 3.75 4.50 0.40 0.60 14.00 16.00 . . . . . .T20826 H26 0.45 0.55E0.15 0.40 0.030 0.030 0.15 0.40 3.75 4.50 0.75 1.25 17.25 19.00 . .
41、. . . .T20841 H41 0.60 0.75E0.15 0.40 0.030 0.030 0.20 0.45 3.50 4.00 1.00 1.30 1.40 2.10 8.20 9.20T20842 H42 0.55 0.70E0.15 0.40 0.030 0.030 0.20 0.45 3.75 4.50 1.75 2.20 5.50 6.75 4.50 5.50T20843 H43 0.50 0.65E0.15 0.40 0.030 0.030 0.20 0.45 3.75 4.50 1.80 2.20 . . . . . . 7.75 8.50T30102 A2 0.95
42、1.05 0.40 1.00 0.030 0.030 0.10 0.50 4.75 5.50 0.15 0.50 . . . . . . 0.90 1.40T30103 A3 1.20 1.30 0.40 0.60 0.030 0.030 0.10 0.70 4.75 5.50 0.80 1.40 . . . . . . 0.90 1.40T30104 A4 0.95 1.05 1.80 2.20 0.030 0.030 0.10 0.70 0.90 2.20 . . . . . . . . . . . . 0.90 1.40T30105 A5 0.95 1.05 2.80 3.20 0.03
43、0 0.030 0.10 0.70 0.90 1.40 . . . . . . . . . . . . 0.90 1.40T30106 A6 0.65 0.75 1.80 2.50 0.030 0.030 0.10 0.70 0.90 1.40 . . . . . . . . . . . . 0.90 1.40T30107 A7 2.00 2.85 0.20 0.80 0.030 0.030 0.10 0.70 5.00 5.75 3.90 5.15 0.50 1.50 0.90 1.40T30108 A8 0.50 0.60 0.20 0.50 0.030 0.030 0.75 1.10 4
44、.75 5.50 . . . . . . 1.00 1.50 1.15 1.65T30109 A9 0.45 0.55 0.20 0.50 0.030 0.030 0.95 1.15 4.75 5.50 0.80 1.40 . . . . . . 1.30 1.80 Ni 1.251.75T30110 A10 1.25 1.50 1.60 2.10 0.030 0.030 1.00 1.50 . . . . . . . . . . . . . . . . . . 1.25 1.75 Ni 1.552.05T30402 D2 1.40 1.60 0.10 0.60 0.030 0.030 0.1
45、0 0.60 11.00 13.00 0.50 1.10 . . . . . . 0.70 1.20 . . .T30403 D3 2.00 2.35 0.10 0.60 0.030 0.030 0.10 0.60 11.00 13.50 . . . 1.00 . . . 1.00 . . . . . .T30404 D4 2.05 2.40 0.10 0.60 0.030 0.030 0.10 0.60 11.00 13.00 0.15 1.00 . . . . . . 0.70 1.20T30405 D5 1.40 1.60 0.10 0.60 0.030 0.030 0.10 0.60
46、11.00 13.00 . . . 1.00 . . . . . . 0.70 1.20 Co 2.503.50T30407 D7 2.15 2.50 0.10 0.60 0.030 0.030 0.10 0.60 11.50 13.50 3.80 4.40 . . . . . . 0.70 1.20T31501 O1 0.85 1.00 1.00 1.40 0.030 0.030 0.10 0.50 0.40 0.70 . . . 0.30 0.40 0.60 . . . . . .T31502 O2 0.85 0.95 1.40 1.80 0.030 0.030 . . . 0.50 .
47、. . 0.50 . . . 0.30 . . . . . . . . . 0.30T31506 O6 1.25 1.55 0.30 1.10 0.030 0.030 0.55 1.50 . . . 0.30 . . . . . . . . . . . . 0.20 0.30T31507 O7 1.10 1.30 0.20 1.00 0.030 0.030 0.10 0.60 0.35 0.85 0.15 0.40 1.00 2.00 . . . 0.30T41901 S1 0.40 0.55 0.10 0.40 0.030 0.030 0.15 1.20 1.00 1.80 0.15 0.3
48、0 1.50 3.00 . . . 0.50T41902 S2 0.40 0.55 0.30 0.50 0.030 0.030 0.90 1.20 . . . . . . . . . 0.50 . . . . . . 0.30 0.60T41904 S4 0.50 0.65 0.60 0.95 0.030 0.030 1.75 2.25 0.10 0.50 0.15 0.35 . . . . . . . . . . . . . . . . . .T41905 S5 0.50 0.65 0.60 1.00 0.030 0.030 1.75 2.25 0.10 0.50 0.15 0.35 . .
49、 . . . . 0.20 1.35 . . . . . .T41906 S6 0.40 0.50 1.20 1.50 0.030 0.030 2.00 2.50 1.20 1.50 0.20 0.40 . . . . . . 0.30 0.50 . . . . . .T41907 S7 0.45 0.55 0.20 0.90 0.030 0.030 0.20 1.00 3.00 3.50 . . . 0.35 . . . . . . 1.30 1.80 . . . . . .T61202 L2 0.45 1.00 0.10 0.90 0.030 0.030 0.10 0.50 0.70 1.20 0.10 0.30 . . . . . . . . . 0.25 . . . . . .T61203 L3 0.95 1.10 0.25 0.80 0.030 0.030 0.10 0.50 1.30 1.70 0.10 0.30 . . . . . . . . . . . . . . . . . .NickelT61206 L6 0.65 0.75 0.25 0.80 0.030 0.030 0.10 0.50 0.60 1.20 . . . . . . . . . . . . . . . 0.50 1.25 2.00T60601
