1、Designation: E 604 83 (Reapproved 2008)Standard Test Method forDynamic Tear Testing of Metallic Materials1This standard is issued under the fixed designation E 604; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r
2、evision. A number in parentheses 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 Department of Defense.1. Scope1.1 This test method covers the dynamic tear (D
3、T) test usingspecimens that are316 in. to58 in. (5 mm to 16 mm) inclusivein thickness.1.2 This test method is applicable to materials with aminimum thickness of316 in. (5 mm).1.3 The pressed-knife procedure described for sharpeningthe notch tip generally limits this test method to materials witha ha
4、rdness level less than 36 HRC.NOTE 1The designation 36 HRC is a Rockwell hardness number of36 on Rockwell C scale as defined in Test Methods E18.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are p
5、rovided for information onlyand are not considered standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-b
6、ility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B 221 Specification for Aluminum and Aluminum-AlloyExtruded Bars, Rods, Wire, Profiles, and TubesE18 Test Methods for Rockwell Hardness of MetallicMaterialsE 399 Test Method for Linear-Elastic Plane-Strain Fractu
7、reToughness KIcof Metallic Materials3. Terminology3.1 Description of Terms Specific to this Standard3.2 Dynamic Tear (DT) Energythe total energy requiredto fracture DT specimens tested in accordance with theprovisions of this test method.NOTE 2With pendulum-type machines, the DT energy is the differ
8、-ence between the initial and the final potential energies of the pendulumor pendulums.NOTE 3With drop-weight machines, the DT energy is the differencebetween the initial potential energy of the hammer and the final energy ofthe hammer as determined by a calibrated energy measurement system.3.3 Perc
9、ent Shear Fracture AppearancePercent shearfracture appearance is the percent of the net section thatfractured in a shear mode. Net section can be either the netsection area before fracture or the area of the projected plane ofthe fracture surface.4. Summary of Test Method4.1 The DT test involves a s
10、ingle-edge notched beam that isimpact loaded in three-point bending, and the total energy lossduring separation is recorded.4.2 The DT specimens are fractured with pendulum ordrop-weight machines.5. Significance and Use5.1 The DT energy value is a measure of resistance to rapidprogressive fracturing
11、. In a number of applications, the en-hanced resistance that may develop during about one platethickness of crack extension from a sharp notch is of majorinterest. In the test method, a sufficiently long fracture path isprovided so that the results serve as a measure of this property.1This test meth
12、od is under the jurisdiction of ASTM Committee E28 onMechanical Testing and is the direct responsibility of Subcommittee E28.07 onImpact Testing.Current edition approved Sept. 1, 2008. Published January 2009. Originallyapproved as a proposed test method in 1975. Last previous edition approved in 200
13、2as E 604 83(2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Ha
14、rbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 Fracture surfaces of nonaustenitic steels tested in theirtemperature transition region have areas that appear bright andareas that appear dull. The bright, faceted appearing areas aretermed “cleavage” fracture, and the dull
15、 appearing areas aretermed “shear” fracture after their respective mode of fractureon a micro scale.5.3 This test method can serve the following purposes:5.3.1 In research and development, to evaluate the effects ofmetallurgical variables such as composition, processing, orheat treatment, or of fabr
16、icating operations such as forming andwelding on the dynamic tear fracture resistance of new orexisting materials.5.3.2 In service evaluation, to establish the suitability of amaterial for a specific application only where a correlationbetween DT energy and service performance has been estab-lished.
17、35.3.3 For information, specifications of acceptance, andmanufacturing quality control when a minimum DT energy isrequested. Detailed discussion of the basis for determiningsuch minimum values in a particular case is beyond the scopeof this test method.6. Apparatus6.1 General RequirementsThe testing
18、 machine shall beeither a pendulum type or a drop-weight type of capacity morethan sufficient to break the specimen in one blow. DT energyvalues above 80 % of the initial potential energy of the bloware invalid. The capacity needed to conduct DT tests on moststeels is 2000 ftlbf (2700 J) for58-in. (
19、16-mm) and 500 ftlbf(700 J) for316-in. (5-mm) thick specimens. The capacityneeded to conduct DT tests on the cast irons and aluminumalloys is less than 20 % of the values given above for moststeels.6.1.1 Velocity LimitationsTests may be made at velocitiesthat range from 13 to 28 ft/s (4.0 to 8.5 m/s
20、). Velocity shall bestated as the velocity between the striker and the specimen atimpact. This range in velocities corresponds to that of hammersdropped from heights of 32 in. to 12 ft (0.8 to 3.7 m).6.1.2 The impact machine shall have a calibrated scale,charts, or direct reading-indicator of initia
21、l and final energyvalues, or the difference between the initial and final energyvalues. The scale, chart, or direct-reading indicator shall bedivided so that DT energy values can be estimated within thefollowing increments:DT Energy Value Maximum Increment600 ftlbf (800 J) 30 ftlbf (40 J)6.1.2.1 The
22、 error in the DT energy value due to an error inthe weight of the pendulum or the dropping weight, or due toan error in drop height, shall not exceed 1 %. Windage andfriction may be compensated for by increasing the height of thedrop, in which case the height may exceed the nominal valueby not over
23、2.0 %.6.1.3 The specimen anvil and the striker tup shall be of steelhardened to a minimum hardness value of 48 HRC and shallconform to the dimensions presented in Fig. 1. Clearancebetween the sides of the hammer and anvil shall not be lessthan 2.0 in. (51 mm), and the center line of the striker edge
24、shall advance in the plane that is within 0.032 in. (0.80 mm) ofthe midpoint between the supporting edges of the specimenanvils. The striker edge shall be perpendicular to the longitu-dinal axis of the specimen within 0.01 rad. When in contactwith the specimen, the striker edge shall be parallel wit
25、hin0.005 rad to the face of a square test specimen held against theanvil. Specimen supports for pendulum machines shall besquare with anvil faces within 0.0025 rad. Specimen supportsshall be coplanar within 0.005 in. (0.125 mm) and parallelwithin 0.002 rad.6.2 The design of the pendulum impact machi
26、nes shallposition the center of percussion at the center of strike within1 % of the distance from the center of rotation to the center ofthe strike. When hanging free, the pendulums shall hang so thatthe striking edge is less than 0.20 in. (5.0 mm) from the edgeposition of the specimen.6.2.1 The loc
27、ation of the center of percussion may bedetermined as follows: Using a stop watch or some othersuitable timer to within 0.2 s, swing the pendulum through atotal angle not greater than 15, and record the time for 100complete cycles (to and fro). Determine the center of percus-sion as follows:l 5 0.81
28、5r2, to determine l in feet (1)l 5 0.2485r2, to determine l in metres3Pellini , W. S., “Analytical Design Procedures for Metals of Elastic-Plastic andPlastic Fracture Properties,” Welding Research Council Bulletin 186, August 1973.Dimensions and Tolerance for Specimen BlankParameter Units Dimension
29、ToleranceLength, L in. 7.125 60.125mm 181 63Width, W in. 1.60 60.10mm 41 62Thickness, B in. 0.625 60.035mm 16 61Angularity, a deg 90 61NOTE 1See 9.1 for specimens less than58-in. (16 mm) thick.FIG. 1 Dynamic Tear Test Specimen, Anvil Supports, and StrikerE 604 83 (2008)2where:l = distance from the a
30、xis to the center of percussion, ft (orm), andr = time of a complete cycle (to and fro) of the pendulum,s.6.2.2 For double-pendulum machines, the center of percus-sion of each pendulum shall be determined separately.7. Safety Hazards7.1 A safety screen shall surround the anvil to restrict theflight
31、of broken specimens.7.2 Precautions shall be taken to protect personnel fromswinging pendulums, dropping weights, flying broken speci-mens, and hazards associated with specimen warming andcooling media.8. Sampling8.1 Notation of the orientation of base metal specimensshall be in accordance with that
32、 recommended in Test MethodE 399.8.2 If the thickness of the product is greater than58 in. (16mm), then a58-in. (16-mm) thick specimen shall be thestandard specimen.9. Test Specimens9.1 Size of SpecimensThe specimen blank shall be B by1.60 by 7.125 in. ( B by 40.6 by 181.0 mm) where B can befrom316
33、to58 in. (5 to 16 mm). The tolerances for thesedimensions are presented in Fig. 1.9.2 Notch DetailThe notch is machined to provide afracture path in test material of 1.125 in. (28.5 mm); the smallextension required for notch sharpening is considered a portionof the nominal net section. Details of th
34、e notch are shown inFig. 2, and the notch dimensions shall conform to the valuesgiven therein.9.3 Procedure for Preparing Notch:9.3.1 Rough MachiningMachine a notch to the dimen-sions shown in Fig. 2. The angular apex portion and particu-larly the final cut on the root radius can be machined with ap
35、recisely ground saw, cutter, electric discharge machine, or anyother machining process that will ensure a final root radius lessthan 0.005 in. (0.13 mm). These machining operations arenormally performed simultaneously for a group of specimens.9.3.2 Pressing Notch TipPressing the sharp tip of thenotc
36、h to the dimensions prescribed in Fig. 2 is performed onindividual specimens. The impression is made with a blade ofhigh-speed tool steel (60 HRC min), which has been ground tothe dimensions presented in Fig. 3, and subsequently honed toremove any burrs or rough edges. Any loading device withsuffici
37、ent capacity to press the knife to the prescribed depthmay be used. The force required to accomplish the pressing isrelated to the hardness and the thickness of the specimen. Theforce required can be approximated by either of the followingformulas:force lbf!547 3 ultimate tensile strength ksi!3B in.
38、!force N!52.9 3 ultimate tensile strength MPa!3B mm!where B = thickness of the specimen.NOTE 4Suggested practices for measuring the pressed tip and forpressing the notch tip are given in the Appendixes.10. Calibration of Apparatus10.1 Single-Pendulum MachineSupport the pendulumhorizontally (90 6 1 f
39、rom the rest position) at a point mostconvenient to react with a weighing device such as a platformscale, balance, or load cell, and determine the weight within0.4 %. Take care to minimize friction at the bearing supportand the weighing support. Measure the length of the momentarm (that is, the hori
40、zontal distance between the center ofrotation and a vertical line that passes through the point ofsupport) within 0.1 %. The potential energy at any angularposition can be calculated from the following formula:Energy 5 weight 3 moment arm 1 2 cos b!where b = the angle displaced when the pendulum is
41、rotatedfrom the position of rest when hanging free. An alternativeprocedure may be used if the distance between the center ofrotation and the center of gravity is known within 0.1 %. Theweight is then determined within 0.4 %, with the pendulumsupported horizontally at a point in line with the center
42、 ofgravity. The potential energy at any position is equal to theweight times the elevation of the center of gravity from the restposition.10.1.1 The friction and windage loss of energy in themachine shall not exceed 2.0 % of the initial energy. Thefriction and windage loss is the difference between
43、the poten-tial energy of the pendulum from the starting position and thepotential energy of the pendulum after it completes its swingwithout a specimen. Compensate the friction and windage lossso that zero energy is indicated when the pendulum is releasedwithout a specimen being present.Dimensions a
44、nd Tolerances for Notch TipParameter Units Dimension ToleranceNet width, (Wa) in. 1.125 60.020mm 28.6 60.5Machined notch width, Nwin. 0.0625 60.005mm 1.59 60.13Machined notch root angle, Nadeg 60 62Machined notch root radius, Nrin. 0.005 maxPressed tip depth, tDmm 0.13 maxin. 0.010 60.005Pressed tip
45、 angle, tamm 0.25 60.13Pressed tip root radius, trdeg 40 65in. 0.001 maxmm 0.025 maxFIG. 2 Details of the Notch in a Dynamic Tear SpecimenE 604 83 (2008)310.1.2 Impact VelocityDetermine the impact velocity, v,of the machine, neglecting friction as follows:v 5 2 gh!1/2where:g = acceleration of gravit
46、y, ft/s2(or m/s2),h = initial elevation of the striking edge, ft (or m), andv = striking velocity, ft/s (or m/s).10.2 Double-Pendulum MachineThe procedure for cali-brating the hammer pendulum and the anvil pendulum shall bein accordance with the procedure in 10.1 for a single-pendulummachine. Calibr
47、ate the anvil pendulum without a specimen inplace.10.2.1 Determine and compensate the friction and windageloss of energy in accordance with the procedure described in10.1.1.10.3 Vertical Drop-Weight Apparatus The dimensions ofthe apparatus shall be such that the falling hammer travels aminimum verti
48、cal distance of 2 in. (51 mm) after contacting thespecimen before measurement is made of the final energy and2.75 in. (70 mm) before an arresting device is activated, asshown in Fig. 4.10.3.1 Calibration of an aluminum block system is requiredfor each lot of blocks machined from a single bar. Segreg
49、ateand mark for identification purposes blocks that have beenprepared from each bar. The initial cross-sectional area ofblocks from one lot shall not vary more than 0.2 %. Determinethe average height of the blocks before and after test and recordwith an error not to exceed 0.0005 in. (0.013 mm). Develop achart of absorbed energy versus deformation of blocks byconducting duplicate tests without a specimen at height incre-ments not to exceed 1 ft (305 mm) through the calibratedrange. Average the deformation values for the two blocks fromeach
