ASTM E604-83(2002)
(Test Method)Standard Test Method for Dynamic Tear Testing of Metallic Materials
Standard Test Method for Dynamic Tear Testing of Metallic Materials
SIGNIFICANCE AND USE
The DT energy value is a measure of resistance to rapid progressive fracturing. In a number of applications, the enhanced resistance that may develop during about one plate thickness of crack extension from a sharp notch is of major interest. In the test method, a sufficiently long fracture path is provided so that the results serve as a measure of this property.
Fracture surfaces of nonaustenitic steels tested in their temperature transition region have areas that appear bright and areas that appear dull. The bright, faceted appearing areas are termed “cleavage” fracture, and the dull appearing areas are termed “shear” fracture after their respective mode of fracture on a micro scale.
This test method can serve the following purposes:
5.3.1 In research and development, to evaluate the effects of metallurgical variables such as composition, processing, or heat treatment, or of fabricating operations such as forming and welding on the dynamic tear fracture resistance of new or existing materials.
5.3.2 In service evaluation, to establish the suitability of a material for a specific application only where a correlation between DT energy and service performance has been established.4
5.3.3 For information, specifications of acceptance, and manufacturing quality control when a minimum DT energy is requested. Detailed discussion of the basis for determining such minimum values in a particular case is beyond the scope of this test method.
SCOPE
1.1 This test method covers the dynamic tear (DT) test using specimens that are 3/16 in. to 5/8 in. (5 mm to 16 mm) inclusive in thickness.
1.2 This test method is applicable to materials with a minimum thickness of 3/16 in. (5 mm).
1.3 The pressed-knife procedure described for sharpening the notch tip generally limits this test method to materials with a hardness level less than 36 HRC.
Note 1—The designation 36 HRC is a Rockwell hardness number of 36 on Rockwell C scale as defined in Test Methods E 18.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:E604–83(Reapproved 2002)
Standard Test Method for
Dynamic Tear Testing of Metallic Materials
This standard is issued under the fixed designation E604; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
NOTE 3—With drop-weight machines, the DT energy is the difference
1. Scope
between the initial potential energy of the hammer and the final energy of
1.1 Thistestmethodcoversthedynamictear(DT)testusing
the hammer as determined by a calibrated energy measurement system.
3 5
specimens that are ⁄16 in. to ⁄8 in. (5 mm to 16 mm) inclusive
3.3 Percent Shear Fracture Appearance—Percent shear
in thickness.
fracture appearance is the percent of the net section that
1.2 This test method is applicable to materials with a
fractured in a shear mode. Net section can be either the net
minimum thickness of ⁄16 in. (5 mm).
sectionareabeforefractureortheareaoftheprojectedplaneof
1.3 The pressed-knife procedure described for sharpening
the fracture surface.
the notch tip generally limits this test method to materials with
a hardness level less than 36 HRC.
4. Summary of Test Method
NOTE 1—The designation 36 HRC is a Rockwell hardness number of
4.1 The DTtest involves a single-edge notched beam that is
36 on Rockwell C scale as defined in Test MethodsE18.
impact loaded in three-point bending, and the total energy loss
during separation is recorded.
2. Referenced Documents
4.2 The DT specimens are fractured with pendulum or
2.1 ASTM Standards:
drop-weight machines.
B221 Specification for Aluminum-Alloy Extruded Bars,
Rods, Wire,
5. Significance and Use
E18 Test Methods for Rockwell Hardness and Rockwell
5.1 The DTenergy value is a measure of resistance to rapid
Superficial Hardness of Metallic Materials
progressive fracturing. In a number of applications, the en-
E399 Test Method for Plane-Strain Fracture Toughness of
hanced resistance that may develop during about one plate
Metallic Materials
thickness of crack extension from a sharp notch is of major
interest. In the test method, a sufficiently long fracture path is
3. Terminology
provided so that the results serve as a measure of this property.
3.1 Description of Terms Specific to this Standard
5.2 Fracture surfaces of nonaustenitic steels tested in their
3.2 Dynamic Tear (DT) Energy—the total energy required
temperature transition region have areas that appear bright and
to fracture DT specimens tested in accordance with the
areas that appear dull. The bright, faceted appearing areas are
provisions of this test method.
termed “cleavage” fracture, and the dull appearing areas are
NOTE 2—With pendulum-type machines, the DT energy is the differ- termed “shear” fracture after their respective mode of fracture
ence between the initial and the final potential energies of the pendulum
on a micro scale.
or pendulums.
5.3 This test method can serve the following purposes:
5.3.1 Inresearchanddevelopment,toevaluatetheeffectsof
metallurgical variables such as composition, processing, or
ThistestmethodisunderthejurisdictionofASTMCommitteeE28onFracture
Testing and is the direct responsibility of Subcommittee E28.07 on Impact Testing.
heattreatment,oroffabricatingoperationssuchasformingand
Current edition approved March 25, 1983. Published July 1983. Originally
welding on the dynamic tear fracture resistance of new or
published as a proposed test method in November 1975. Last previous edition
existing materials.
E604–80.
Annual Book of ASTM Standards, Vol 02.02.
Annual Book of ASTM Standards, Vol 03.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E604–83 (2002)
5.3.2 In service evaluation, to establish the suitability of a
material for a specific application only where a correlation
between DT energy and service performance has been estab-
lished.
5.3.3 For information, specifications of acceptance, and
manufacturing quality control when a minimum DT energy is
requested. Detailed discussion of the basis for determining
such minimum values in a particular case is beyond the scope
of this test method.
6. Apparatus
6.1 General Requirements—The testing machine shall be
either a pendulum type or a drop-weight type of capacity more
than sufficient to break the specimen in one blow. DT energy
values above 80% of the initial potential energy of the blow
are invalid. The capacity needed to conduct DT tests on most
steels is 2000 ft·lbf (2700 J) for ⁄8-in. (16-mm) and 500 ft·lbf
(700 J) for ⁄16-in. (5-mm) thick specimens. The capacity
Dimensions and Tolerance for Specimen Blank
needed to conduct DT tests on the cast irons and aluminum
Parameter Units Dimension Tolerance
alloys is less than 20% of the values given above for most
Length, L in. 7.125 60.125
steels.
mm 181 63
6.1.1 Velocity Limitations—Tests may be made at velocities
Width, W in. 1.60 60.10
that range from 13 to 28 ft/s (4.0 to 8.5 m/s). Velocity shall be
mm 41 62
Thickness, B in. 0.625 60.035
stated as the velocity between the striker and the specimen at
mm 16 61
impact.Thisrangeinvelocitiescorrespondstothatofhammers
Angularity, a deg 90 61
dropped 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,
NOTE 1—See 9.1 for specimens less than ⁄8-in. (16 mm) thick.
charts, or direct reading-indicator of initial and final energy FIG. 1 Dynamic Tear Test Specimen, Anvil Supports, and Striker
values, or the difference between the initial and final energy
values. The scale, chart, or direct-reading indicator shall be
square with anvil faces within 0.0025 rad. Specimen supports
divided so that DT energy values can be estimated within the
shall be coplanar within 0.005 in. (0.125 mm) and parallel
following increments:
within 0.002 rad.
DT Energy Value Maximum Increment
6.2 The design of the pendulum impact machines shall
<40 ft·lbf (54 J) 2 ft·lbf (3 J)
position the center of percussion at the center of strike within
40–600 ft·lbf (54–800 J) 5 % of DT energy
>600 ft·lbf (800 J) 30 ft·lbf (40 J)
1% of the distance from the center of rotation to the center of
thestrike.Whenhangingfree,thependulumsshallhangsothat
6.1.2.1 The error in the DT energy value due to an error in
the striking edge is less than 0.20 in. (5.0 mm) from the edge
the weight of the pendulum or the dropping weight, or due to
position of the specimen.
an error in drop height, shall not exceed 1%. Windage and
6.2.1 The location of the center of percussion may be
frictionmaybecompensatedforbyincreasingtheheightofthe
determined as follows: Using a stop watch or some other
drop, in which case the height may exceed the nominal value
suitable timer to within 0.2 s, swing the pendulum through a
by not over 2.0%.
total angle not greater than 15°, and record the time for 100
6.1.3 Thespecimenanvilandthestrikertupshallbeofsteel
complete cycles (to and fro). Determine the center of percus-
hardened to a minimum hardness value of 48 HRC and shall
sion as follows:
conform to the dimensions presented in Fig. 1. Clearance
between the sides of the hammer and anvil shall not be less
l 50.815r ,todetermine linfeet (1)
than 2.0 in. (51 mm), and the center line of the striker edge
l 50.2485r2, todetermine linmetres
shall advance in the plane that is within 0.032 in. (0.80 mm) of
the midpoint between the supporting edges of the specimen where:
anvils. The striker edge shall be perpendicular to the longitu- l = distancefromtheaxistothecenterofpercussion,ft(or
m), and
dinal axis of the specimen within 0.01 rad. When in contact
r = time of a complete cycle (to and fro) of the pendulum,
with the specimen, the striker edge shall be parallel within
s.
0.005 rad to the face of a square test specimen held against the
6.2.2 For double-pendulum machines, the center of percus-
anvil. Specimen supports for pendulum machines shall be
sion of each pendulum shall be determined separately.
7. Safety Hazards
See Pellini, W. S., “Analytical Design Procedures for Metals of Elastic-Plastic
7.1 A safety screen shall surround the anvil to restrict the
and Plastic Fracture Properties,” Welding Research Council Bulletin 186, August
1973. flight of broken specimens.
E604–83 (2002)
7.2 Precautions shall be taken to protect personnel from 9.3.2 Pressing Notch Tip—Pressing the sharp tip of the
swinging pendulums, dropping weights, flying broken speci- notch to the dimensions prescribed in Fig. 2 is performed on
mens, and hazards associated with specimen warming and individual specimens. The impression is made with a blade of
cooling media. high-speed tool steel (60 HRC min), which has been ground to
the dimensions presented in Fig. 3, and subsequently honed to
8. Sampling remove any burrs or rough edges. Any loading device with
sufficient capacity to press the knife to the prescribed depth
8.1 Notation of the orientation of base metal specimens
may be used. The force required to accomplish the pressing is
shall be in accordance with that recommended in Test Method
related to the hardness and the thickness of the specimen. The
E399.
5 force required can be approximated by either of the following
8.2 If the thickness of the product is greater than ⁄8 in. (16
formulas:
mm), then a ⁄8-in. (16-mm) thick specimen shall be the
standard specimen. force ~lbf!547 3ultimatetensilestrength ~ksi!3 B ~in.!
force ~N!52.9 3ultimatetensilestrength ~MPa!3 B ~mm!
9. Test Specimens
where B =thickness of the specimen.
9.1 Size of Specimens—The specimen blank shall be B by
1.60 by 7.125 in. ( B by 40.6 by 181.0 mm) where B can be NOTE 4—Suggested practices for measuring the pressed tip and for
3 5
pressing the notch tip are given in the Appendixes.
from ⁄16 to ⁄8 in. (5 to 16 mm). The tolerances for these
dimensions are presented in Fig. 1.
10. Calibration of Apparatus
9.2 Notch Detail—The notch is machined to provide a
fracture path in test material of 1.125 in. (28.5 mm); the small
10.1 Single-Pendulum Machine—Support the pendulum
extensionrequiredfornotchsharpeningisconsideredaportion
horizontally (90 6 1° from the rest position) at a point most
of the nominal net section. Details of the notch are shown in
convenient to react with a weighing device such as a platform
Fig. 2, and the notch dimensions shall conform to the values
scale, balance, or load cell, and determine the weight within
given therein.
0.4%. Take care to minimize friction at the bearing support
9.3 Procedure for Preparing Notch:
and the weighing support. Measure the length of the moment
9.3.1 Rough Machining—Machine a notch to the dimen-
arm (that is, the horizontal distance between the center of
sions shown in Fig. 2. The angular apex portion and particu-
rotation and a vertical line that passes through the point of
larly the final cut on the root radius can be machined with a
support) within 0.1%. The potential energy at any angular
preciselygroundsaw,cutter,electricdischargemachine,orany
position can be calculated from the following formula:
othermachiningprocessthatwillensureafinalrootradiusless
Energy 5weight 3momentarm ~1 2cos b!
than 0.005 in. (0.13 mm). These machining operations are
normally performed simultaneously for a group of specimens.
where b=the angle displaced when the pendulum is rotated
from the position of rest when hanging free. An alternative
procedure may be used if the distance between the center of
rotation and the center of gravity is known within 0.1%. The
weight is then determined within 0.4%, with the pendulum
supported horizontally at a point in line with the center of
gravity. The potential energy at any position is equal to the
weighttimestheelevationofthecenterofgravityfromtherest
position.
10.1.1 The friction and windage loss of energy in the
machine shall not exceed 2.0% of the initial energy. The
friction and windage loss is the difference between the poten-
tial energy of the pendulum from the starting position and the
potential energy of the pendulum after it completes its swing
Dimensions and Tolerances for Notch Tip
without a specimen. Compensate the friction and windage loss
Parameter Units Dimension Tolerance
so that zero energy is indicated when the pendulum is released
Net width, (W−a) in. 1.125 60.020
without a specimen being present.
mm 28.6 60.5
10.1.2 Impact Velocity—Determine the impact velocity, v,
Machined notch width, N in. 0.0625 60.005
w
mm 1.59 60.13
of the machine, neglecting friction as follows:
Machined notch root angle, N deg 60 62
a
1/2
v 5 ~2 gh!
Machined notch root radius, N in. 0.005 max
r
Pressed tip depth, t mm 0.13 max
D
in. 0.010 60.005
Pressed tip angle, t mm 0.25 60.13
a
where:
Pressed tip root radius, t deg 40 65 2 2
r
g = acceleration of gravity, ft/s (or m/s ),
in. 0.001 max
h = initial elevation of the striking edge, ft (or m), and
mm 0.025 max
v = striking velocity, ft/s (or m/s).
FIG. 2 Details of the Notch in a Dynamic Tear Specimen
E604–83 (2002)
FIG. 3 Knife for Sharpening Tip of Notch in Dynamic Tear Specimen
10.2 Double-Pendulum Machine—The procedure for cali-
DT Energy Value Stiffness per Block
50 ft·lbf (74 J) and under 1 ft·lbf/0.001 in. (54 J/mm)
brating the hammer pendulum and the anvil pendulum shall be
greater than 50 ft·lbf (74 J) 2.5 ft·lbf/0.001 in. (136 J/mm)
inaccordancewiththeprocedurein10.1forasingle-pendulum
machine. Calibrate the anvil pendulum without a specimen in This level of sensitivity permits the use of two aluminum
blockshavinganinitialheightof1.5in.(40mm)andaninitial
place.
10.2.1 Determine and compensate the friction and windage diameter of 0.5 in. (13 mm) when less than 1000 ft lbf (1400
J) are absorbed by the two blocks. The material can be
loss of energy in accordance with the procedure described in
10.1.1. Specification B221 alloy 1060, 1100, or 6061 in the O temper
condition or after annealing at 775°F (413°C) and furnace
10.3 Vertical Drop-Weight Apparatus— The dimensions of
the apparatus shall be such that the falling hammer travels a cooling. Testing of DT specimens shall be conducted with the
aluminum blocks at the same temperature used for calibration
minimumverticaldistanceof2in.(51mm)aftercontactingthe
specimen before measurement is made of the final energy and within 10°F (5.6°C).
10.3.2 The friction and windage loss shall not decrease the
2.75 in. (70 mm) before an arresting device is activated, as
shown in Fig. 4. velocity of the strike by more than 1% of the
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