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استاندارد ASTM D 1037 – 99 (بخش دوم)
D 1037
9
fastener like a staple or roofing nail may be desired instead of a common
nail. If for any reason a different fastener than the common nail is used, the
report of the test shall describe the fastener actually used.
56. Specimens Tested in the Dry Conditions
56.1 When the tests are made in the dry state, the pullthrough
shall be made immediately after the nails have been
driven
57. Specimens Soaked Before Test
57.1 Specimens to be tested in the soaked condition shall be
prepared in accordance with Section 13, and the nails shall be
driven before the specimens are soaked.
58. Method of Loading
58.1 Modify the assembly for the direct withdrawal test
detailed in Fig. 11 by replacing the top pair of angles in the
specimen-holding fixture with a 6-in. (152-mm) length of 6 by
21⁄4-in. (152 by 57-mm) American standard channel. The web
of the channel shall have a 3-in. (76-mm) diameter opening
centered in the web. The edge of this opening provides the
support to the specimen during test. Center the specimenholding
fixture and attach it to the lower platen of the testing
machine. Insert the specimen in the holding fixture with the
point of the nail up. Grip the pointed end of the nail with a
tension grip or “Jacob’s-type drill chuck” which is attached to
the upper platen of the testing machine with a universal joint or
toggle linkage, to provide for automatic aligning. Apply loads
by separation of the platens of the testing machine. For other
Metric Equivalents
in. 1⁄16 1⁄8 3⁄16 3⁄8 1⁄2 5⁄8 3⁄4 7⁄8 1 11⁄8 11⁄4 21⁄4
mm 1.5 3 4.5 9 12.7 15 19 21 25.4 28 32 57
FIG. 9 Detail of Stirrups and Connections for Measuring the Resistance of Nails to Lateral Movement
FIG. 10 Test Assembly for Measuring the Resistance of Nails to
Direct Withdrawal
NOTE 1—1 in. = 25.4 mm.
FIG. 11 Details of Testing Equipment for Measuring the
Resistance of Nails to Direct Withdrawal
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types of fasteners than nails, it may be necessary to modify the
chuck or tension-grip type of loading fixture.
59. Speed of Testing
59.1 Apply the load to the specimen throughout the test by
a uniform motion of the movable head of the testing machine
at a rate of 0.06 in./min (1.5 mm/min) (see Note 8).
60. Test Data and Report
60.1 The maximum load required to pull the head of the nail
or other fastener through the board shall be the measure of
resistance of the material to nail-head pull-through, and shall
be included in the report. The report shall describe the type of
fastener used and the failure.
DIRECT SCREW WITHDRAWAL TEST
61. Scope
61.1 Screw-holding tests shall be made on screws threaded
into the board to measure the resistance to withdrawal in a
plane normal to the face. For numerous applications, the
withdrawal resistance of screws from the edge of the board is
desired. When that value is required the screw withdrawal
resistance in the plane parallel to the face shall be determined.
When general information is desired for comparing the screw
withdrawal resistance of a board with another board or
material, the No. 10, 1-in. (25-mm) Type AB sheet metal screw
(Note 25) shall be used. For special applications, however, this
procedure is adaptable to other sizes and types of screws.
62. Test Specimen
62.1 Withdrawal Perpendicular to the Plane of the Board—
The test specimen shall be at least 3 in. (76 mm) in width by
4 in. (102 mm) in length. The thickness of the specimen shall
be at least 1 in. (25 mm) unless other considerations make it
desirable to test with the thickness as manufactured because
local bending of the board at withdrawal may affect test results.
If necessary, glue up two or more thicknesses of the board to
arrive at the 1-in. minimum thickness. One-inch, No. 10 Type
AB sheet metal screws (Note 25) shall be threaded into the
specimen 2⁄3 in. (17 mm). Lead holes shall be predrilled using
a drill 0.125 in. (3.2 mm) in diameter (Note 27).
62.2 Withdrawal from the Edge of the Board—The test
specimen shall be 3 in. (76 mm) in width by at least 6 in. (152
mm) in length and the thickness of the board as manufactured
(Note 26). One half of the test specimens shall be prepared
with the long dimension parallel and the other half with the
long dimension perpendicular to the long dimension of the
board in order to evaluate directional properties.A1-in., No. 10
Type AB sheet metal screw (Note 25) shall be threaded into the
edge of the board at midthickness 2⁄3 in. (17 mm). Lead holes
shall be predrilled using a drill 0.125 in. (3.2 mm) in diameter
(Note 27).
NOTE 25—Number 10 Type AB screws should have a root diameter
0.138 6 0.003 in. (3.51 6 0.1 mm) and a pitch of 16 threads per inch.
NOTE 26—In some applications where several thicknesses of hardboard
or the thinner particle board are laminated together, it may be desirable to
obtain the edge withdrawal resistance of a laminated board. When this is
done, the specimen shall be laminated from an odd number of thicknesses
and the screws shall be located at the midthickness of the center laminate.
NOTE 27—It is recognized that some other lead hole diameter may give
higher withdrawal resistance values for some densities and kinds of board.
Departures from this size of lead hole are permitted, but diameter used
shall be reported.
63. Specimens Tested in the Dry Condition
63.1 When the tests are made in the dry state, the withdrawals
shall be made immediately after the screws have been
embedded.
64. Specimens Soaked Before Test
64.1 Specimens to be tested in the soaked condition shall be
prepared in accordance with Section 13, and the screws shall
be embedded before the specimens are soaked.
65. Method of Loading
65.1 The assembly for the direct screw withdrawal is the
same as shown for direct nail withdrawal in Fig. 10. Attach the
specimen-holding fixture to the lower platen of the test
machine. Insert the specimen in the fixture with the heads of
the screws up as shown. Engage the heads of the screws by the
load-applying fixture equipped with a slot for easy attachment.
Attach this loading fixture to the upper platen of the testing
machine. Apply loads by separation of the platens of the testing
machine.
66. Speed of Testing
66.1 Apply the load to the specimen throughout the test by
a uniform motion of the movable head of the testing machine
at a rate of 0.6 in./min (15 mm/min) (see Note 8).
67. Report
67.1 The report shall include the following:
67.1.1 Diameter of lead hole actually used, indicating both
type and size of screw,
67.1.2 Any departures for other size of fastener,
67.1.3 Type of withdrawal, differentiated as surface (withdrawal
perpendicular to the plane of the board) or edge
(withdrawal parallel to the plane of the board) resistance,
67.1.4 Thickness of the board as actually tested, and
67.1.5 If the screw is broken rather than withdrawn, it shall
be noted and the test value shall not be included in those values
presented in the reports as values of withdrawal.
HARDNESS TEST
68. Scope
68.1 The modified Janka ball test shall be used for determining
hardness.
69. Test Specimen
69.1 Each specimen shall be nominally 3 in. (75 mm) in
width and 6 in. (150 mm) in length and at least 1 in. (25 mm)
thick. Because most boards are manufactured in thicknesses of
less than 1 in. (25 mm), the specimen for test shall be made by
bonding together several layers of the panel to make the
required thickness. A rubber cement or other suitable flexible
adhesive shall be used. The finished specimen shall be trimmed
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after bonding so that edges are smooth. The dimensions of the
specimens as tested shall be measured to an accuracy of not
less than 60.3 %.
70. Procedure
70.1 Use of modified ball test with a “ball” 0.444 in. (11.28
mm) in diameter (100 mm2 projected area) for determining
hardness. Record as the measure of hardness the load at which
the “ball” has penetrated to one half its diameter, as determined
by an electric circuit indicator or by the tightening of the collar
against the specimen. The test assembly with a tool of the
tightening collar type is shown in Fig. 12.
71. Number of Penetrations
71.1 Make two penetrations on each of the two flat faces of
the board. Where one face is different than the other, as for
example the smooth face and wire-textured back of most
hardboards, report the data obtained from the two faces
separately. The locations of the points of penetration shall be at
least 1 in. (25 mm) from the edges and ends of the specimen
and far enough apart so that one penetration will not affect
another one.
72. Speed of Testing
72.1 Apply the load continuously throughout the test at a
uniform rate of motion of the movable crosshead of the testing
machine of 0.25 in./min (6 mm/min) (see Note 8).
73. Test Data and Report
73.1 The maximum load required to embed the “ball” to one
half its diameter shall be the measure of hardness, and shall be
included in the report.
HARDNESS MODULUS TEST
74. Scope
74.1 The hardness modulus method of determining “equivalent
Janka ball hardness” may be used for determining hardness
of building fiberboards and particle boards.
75. Significance and Use
75.1 The hardness modulus (in pounds per inch of penetration)
divided by 5.4 gives the equivalent Janka ball hardness in
pounds.7 The thinness of most wood-base panel materials
precludes the use of the regular Janka ball procedure (see
Methods D 143) unless several thicknesses are laminated
together to provide a thickness of about 1 in. (25 mm) or more.
75.2 This procedure is applicable for materials greater in
thickness than 1⁄8 in. (3 mm). For thicknesses 1⁄8 in. or less,
stacks of material may be used, but extreme care must be used
to select the proper slope for hardness modulus.
76. Test Specimen
76.1 Each specimen shall be nominally 3 in. (75 mm) in
width and 6 in. (150 mm) in length by the thickness of the
material. When materials are 1⁄4 in. (6 mm) or less in thickness,
an extra specimen shall be prepared as a backing material
during the test. The finished specimen shall be sawed square
with smooth edges. The dimensions of the specimens as tested
shall be measured to an accuracy of not less than 60.3 %.
77. Procedure
77.1 The rate of penetration of the modified Janka ball,
0.444 in. (11.3 mm) in diameter (100 mm2 projected area),
shall be used for determining hardness modulus. Suitable
modifications of the Janka ball hardness apparatus to measure
penetration are shown in Fig. 13 and Fig. 14. Fig. 13 shows the
modification manual measurements of penetration and Fig. 14
shows a cone unit with microformer for autographic recording.
Fig. 15 shows the kind of load-penetration data obtained from
tests. Each test shall be continued until the penetration is about
0.1 in. (2.5 mm). The slope of the straight-line portion of the
load penetration curve in pounds per inch shall be the hardness
modulus. The equivalent Janka ball hardness value in pounds is
obtained dividing this hardness modulus by the factor 5.4.
78. Number of Penetrations
78.1 At least two penetrations shall be made on each of the
two flat faces of each specimen. Where one face is different
from the other as, for example, the smooth face and wiretextured
back of most hardboards, the data obtained from the
two faces shall be reported separately. The locations of the
points of penetration shall be at least 1 in. (25 mm) from the
edges and ends of specimens and far enough apart so that one
penetration will not affect another one.
7 For further information on this relationship consult “Hardness Modulus as an
Alternate Measure of Hardness to the Janka Ball for Wood and Wood-Base
Materials,” by W. C. Lewis, U.S. Forest Service, research note FPL-0189, March
1968. Available from Forest Products Laboratory, One Gifford Pinchot Dr.,
FIG. 12 Janka Ball Test Apparatus for Hardness of Fiberboards Madison, WI 53705-2398.
D 1037
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79. Speeding of Testing
79.1 The load shall be applied continuously throughout the
test at a uniform rate of motion of the movable crosshead of the
testing machine of 0.05 in./min (1.3 mm/min) (see 1.3).
80. Test Data and Report
80.1 The hardness modulus as determined from the loadpenetration
curve and the calculated equivalent Janka ball
hardness value shall be included in the report. When moisture
content or specific gravity, or both, are required, this shall be
determined as specified in Sections 127 and 128 and included
in the report.
SHEAR STRENGTH IN THE PLANE OF THE
BOARD
81. Scope
81.1 Shear strength tests shall be made on specimens
prepared by laminating each specimen so that the plane of the
FIG. 13 Janka-Ball Hardness Tool Equipped with a Micrometer Dial for Measuring Penetration
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shear failure will be in the board proper and not in the glue
lines. This test, except for the method of preparing the
specimen, follows the procedure described in Section 90 to 94
of Methods D 143.
82. Test Specimen
82.1 The shear-parallel-to-plane of board tests shall be
made on 2 by 2 by 21⁄2-in. (50 by 50 by 63-mm) specimens
notched as illustrated in Fig. 16. It is the intent in this test to
have the plane of shear parallel to the surfaces of the board and
to have the failure approximately midway between the two
surfaces of the board. The specimen shall be glued up by
laminating sufficient thicknesses (Note 28) of the board together
to produce the desired 2-in. (50-mm) thickness of
specimen as shown in Fig. 16. The actual area of the shear
surface shall be measured.
NOTE 28—When the shear strength of a thin board like hardboard is
desired, it will be permissible to use a thicker material such as plywood for
outer laminations to reduce the total amount of gluing. When that
procedure is used, at least the center lamination and preferably the three
center laminations shall be of the board under test.
83. Procedure
83.1 Use a shear tool similar to that illustrated in Fig. 18 of
Methods D 143, providing a 1⁄8-in. (3-mm) offset between the
inner edge of the supporting surface and the plane, along which
failure occurs. Apply the load to, and support the specimen on,
the ends of the specimens as indicated by the large arrow in
FIG. 14 Janka-Ball Hardness Tool Adapted with Cone and Microformer Unit for Direct Autographic Recording of Load-
Penetration Data
D 1037
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Fig. 16. Take care in placing the specimens in the shear tool to
see that the crossbar is adjusted so that the edges of the
specimen are vertical and the end rests evenly on the support
over the contact area. Observe the maximum load only.
84. Speed of Testing
84.1 Apply the load continuously throughout the test at a
uniform rate of motion of the movable crosshead of the testing
machine of 0.024 in./min (0.61 mm/min) (see Note 8).
85. Test Failures
85.1 Record the character and type of failure. In all cases
where the failure at the base of the specimen extends back onto
the supporting surface, the test shall be culled.
86. Moisture Content
86.1 Use the portion of the specimen that is sheared off as a
moisture specimen.
GLUE-LINE SHEAR TEST (BLOCK TYPE)
87. Scope
87.1 The block-type glue-line shear test shall be used to
evaluate glued board constructions such as are obtained when
thicknesses are laminated together to provide a greater thickness
than when manufactured. When desired, the specimens
may be modified to evaluate glue lines between the test
material and solid wood or veneer by laminating the specimen
so that the glue line to be evaluated is so oriented in the
specimen that it coincides with the plane of shear in the
specimen. This test procedure is adopted from Test Method
D 905, except for the rate of loading (see 89.1).
88. Test Specimen
88.1 The test specimen shall be 2 in. (50 mm) in width and
2 in. in height, and shall be fabricated as shown in Fig. 17. The
specimen shall be from 1 to 2 in. (25 to 50 mm) thick, as
necessary, depending on the thickness of the board (Note 29).
Specimens shall be sawed from panels glued up in sizes of at
least 6-in. (152-mm) square. Care shall be taken in preparing
test specimens to make the loaded surfaces smooth and parallel
to each other and perpendicular to the glue line in the shear
plane. Care shall be exercised in reducing the lengths of the
laminations to 13⁄4 in. (44 mm) to ensure that the saw cuts
extend to, but not beyond the glue line. The width and height
FIG. 15 Typical Load-Indentation Lines Obtained with Autographic Equipment for Wood and Wood-Base Panel Materials. Values Shown
on Triangles Were Ones Used to Compute the Hardness Modulus Values
Metric Equivalents
in. 1⁄2 3⁄4 11⁄4 2 21⁄2
mm 12.7 19 31.7 51 63.5
FIG. 16 Shear Parallel to Surface Test Specimen
D 1037
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of the specimen at the glue line shall be measured to at least the
nearest 0.01 in. (0.25 mm). These measurements shall determine
the shear area.
NOTE 29—When the glue-line shear strength of a thin board like
hardboard is desired, it will be permissible to use a thicker material such
as plywood for outer laminations to reduce the total amount of gluing. The
material on either side of the glue line in the plane of shear shall be the
board under test unless the test involves a glue line of board and another
material.
89. Loading Procedure
89.1 Apply the load through a self-aligning seat to ensure
uniform lateral distribution of load. Apply the load with a
continuous motion of the movable head of the testing machine
at 0.024 in. (0.6 mm)/min. Use the loading tool required for the
shear in the plane of the board test, adjusted so that failure will
occur along or adjacent to the glue line (no offset), to load the
specimen. The shear tool is shown in detail in Fig. 1 of Test
Method D 905.
90. Test Failures
90.1 Report the shear stress at failure, based on the maximum
load, the overlap area between the two laminations, and
the percentage of fiber failure, for each specimen.
FALLING BALL IMPACT TEST
91. Scope
91.1 The falling ball impact test shall be used to measure the
impact resistance of boards from the kind of damage that
occurs in service when struck by moving objects. In this test a
2-in. (50-mm) diameter steel ball is dropped on a supported
panel of board from increasing heights, each drop being made
at the same point, the center, in the panel, until the panel fails.
The height of drop in inches that produces a visible failure on
the opposite face of the one receiving the impact is recorded as
the index of resistance to impact.
92. Apparatus
92.1 A suitable assembly for making the falling ball impact
test is shown in Fig. 18. Two frames of 11⁄2-in. (38-mm) thick
plywood, 9 by 10-in. (228 by 254-mm) outside dimension with
a 6-in. (152-mm) central square shall be provided with eight
3⁄8-in. (9-mm) carriage bolts for clamping the specimen between
the frames. The eight bolts shall be spaced equidistant on
and 85⁄8-in. (218-mm) diameter circle. A 2-in. (50-mm) diameter
steel ball (weighing 1.18 lb, 536 g) and a suitable means
of holding and releasing it from predetermined heights shall be
provided. During the test the frame and specimen shall be
supported solidly on a suitable base.
93. Test Specimen
93.1 The impact test specimens shall be 9 by 10 in. (228 by
254 mm) by the thickness of the material. No facing material
other than that which is a regular part of the board shall be
applied to the board prior to test.
94. Procedure
94.1 Before the test, clamp the specimen securely between
the frames. Drop the steel ball with an initial drop of 1 in. (25
mm) so that it strikes approximately at the center of the
specimen. Make repeated drops from increasing heights until a
visible fracture is produced on the top surface and on the
bottom surface of the specimen. Increments of drop shall be 1
in. (25 mm), measuring the distance from the bottom of the ball
to the top surface of the specimen. Record the heights of drop
that produce the visible fractures on the two surfaces. Catch the
ball after each drop so that there will be only one impact for
each drop.
95. Report
95.1 The report shall include the following:
95.1.1 Description of the failure,
95.1.2 Heights of drop that produced failures on each face,
and
Metric Equivalents
in. 1⁄4 1 13⁄4 2
mm 6 25.4 44 51
FIG. 17 Block-Type Glue-Line Shear Test Specimen
FIG. 18 Test Assembly for Falling Ball Impact Test
D 1037
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95.1.3 The measured thickness of each test specimen.
ABRASION RESISTANCE BY THE U.S. NAVY
WEAR TESTER
96. Scope
96.1 Abrasion resistance tests shall be made on the board to
determine the wear under simulated conditions of uniform
abrasion.
NOTE 30—Other test methods have been used to measure abrasion
resistance of other materials. The test method delineated here has been
used extensively for measuring the resistance of wood and other woodbase
materials like plywood to surface abrasion, so values are available for
comparing the resistance of wood-base fiber and particle panel materials
with the materials most commonly used alternately to them.8
97. Test Specimen
97.1 The area of the test specimen to be abraded shall be 2
by 3 in. (50 by 76 mm), and the specimen shall be fabricated
from a piece of the board 2 by 4 in. (50 by 101 mm) by the
thickness of the material (Note 31) as shown in Fig. 19. The
specimens shall be conditioned before test (see Section 6) and
the test made in the same conditioned atmosphere. The actual
dimensions of the abrading area of the specimen shall be
measured to the nearest 0.01 in. (0.2 mm). The thickness of the
test specimen shall be measured to at least the nearest 0.001 in.
(0.02 mm) near each corner and the center.
NOTE 31—When the board tested is less than 1⁄2 in. (12 mm) thick,
either sufficient thicknesses shall be laminated together to provide the
1⁄2-in. thickness or the specimen shall be backed by a thickness of wood
or plywood sufficient to provide the 1⁄2-in. total thickness of specimen
required.
98. Procedure
98.1 Conduct the test on the Navy-type abrasion machine9
as shown in Fig. 20, using as the abrading medium new No.
80-grit aluminum oxide, or equivalent. Apply the grit continuously
(Note 32) to the 14-in. (355-mm) diameter steel disk,
which serves as a platform supporting the specimen and rotates
at the rate of 231⁄2 r/min. Rotate the specimen in the same
direction as the steel disk at the rate of 321⁄2 r/min. Superimpose
a load of 10 lb (4.5 kg) on the test specimen. The machine
is designed so that twice each revolution the specimen is raised
1⁄16 in. (1.6 mm) above the steel disk and immediately lowered.
Determine the decrease in the thickness of the specimen at the
end of each 100 revolutions of the steel disk by measuring the
thickness of the specimen to the nearest 0.001 in. (0.02 mm)
near each corner and at the center, after brushing to remove any
dust or abrading material adhering to the surface of the
specimen. The mean of the five recordings shall be taken as the
loss in thickness. Repeat this procedure until the specimen has
500 revolutions of wear or as required (Note 33).
NOTE 32—The Navy wear tester is designed so that there is an excess
of grit on the abrading disk at all times. During all parts of the abrading
action, except when the specimen is in the raised position, the specimen
is pushing a small amount of grit ahead of it.
NOTE 33—When values of accumulated wear are plotted as ordinates
against revolutions, the slope of the curve is a straight line for wear
through uniform materials. When the rate of wear per 100 revolutions of
the abrading disk is not uniform after the first 200 revolutions, it is
probably due to a change in abrasion resistance with depth from the
original surface of the material being tested.
99. Report
99.1 The report shall include the following:
99.1.1 Loss in thickness in inches per 100 revolutions of
wear if uniform, and
99.1.2 If the amount of wear changes with depth from the
original, surface values for each 100 revolutions.
