1Scope
This method covers the determination of the force
required to initiate tearing in flexible insulating materials.It is bad on ASTM D1004.
2Applicable Documents
ASTM D374
Standard Test Methods for Thickness of Solid打印机出错
Electrical Insulation
ASTM D1004Standard Test Method for Tear Resistance
(Graves Tear)of Plastic Film and Sheeting
3Test Specimens
3.1The specimens shall be prepared using flexible dielec-tric material.If the flexible dielectric is clad,the copper foil shall be etched using standard commercial practices.女孩名字木字旁
3.2
Ten specimens,five in the transver and five in the lon-gitudinal (machine)directions,shall be cut from the sample material.
3.3
The test specimens shall conform to the dimensions shown in Figure 1.
4Test Equipment
4.1Testing Machines
A power driven machine of either of
the two following types shall be ud.
4.1.1Static Weighing
Constant rate of grip paration
type,negligible movement of the upper jaw.
4.1.2Pendulum Weighing
Constant rate of grip motion
type,constant rate of lower jaw movement,variable upper jaw movement.Either maximum load indicating devices or record-ers are permissible in the testing machine.The applied load,as indicated by a recorder,dial or scale,shall be accurate to within 12percent.If an indicating device is ud,the indicator shall remain at the point of maximum load after rupture of the test specimen.
4.2Grips
A gripping system that minimizes both slippage
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and uneven stress distribution on the specimen shall be ud.
4.3Thickness Measuring Devices
Suitable calibrated
ratchet/friction thimble machinist’s micrometer reading to 0.0025mm [0.0001in]or less shall be ud for measuring the thickness of the specimens.The micrometer shall con-form to ASTM D374.
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4.4Die
A die having the dimensions shown in Figure 1
shall be ud to cut all specimens.The 90°angle shall be honed sharp with no radius or have a minimum practical radius,as per ASTM D1004.The cutting edge of the die shall have a 5°negative rake,and shall be kept sharp and free from nicks to avoid leaving ragged edges on the specimen.Cutting may be facilitated by wetting the surface of the sample and cutting edges of the die with water.The sample shall rest on a smooth,slightly yielding surface that will not injure the die blade.Lightweight cardboard or a piece of leather belting is suitable.Care should be taken that the cut edges of the speci-men are perpendicular to its other surfaces and that the edges have a minimum of concavity.NOTE:The test speci-men results depend on the quality of the die ud.
Figure 1Die for Tear Test Specimen
3000Lakeside Drive,Suite 309S
Bannockburn,IL 60015-1249
IPC-TM-650
TEST METHODS MANUAL
Number 2.4.16
Subject
胸口有痣的女人Initiation Tear Strength,Flexible Insulating Materials Date 03/14
宏伟近义词Revision B
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Originating Task Group
Flexible Circuits Test Methods Subcommittee (D-15)
Material in this Test Methods Manual was voluntarily established by Technical Committees of IPC.This material is advisory only and its u or adaptation is entirely voluntary.IPC disclaims all liability of any kind as to the u,application,or adaptation of this material.Urs are also wholly responsible for protecting themlves against all claims or liabilities for patent infringement.Equipment referenced is for the convenience of the ur and does not imply endorment by IPC.
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5Conditioning
5.1Conditioning The test specimens shall be conditioned at23°C±2°C(73.4°F±3.6°F)and50%±5%relative humidity for not less than24hours prior to test.
5.2Test Conditions Conduct tests in the Standard Labo-ratory Atmosphere of23°C±2°C(73.4°F±3.6°F)and50±10percent relative humidity.
6Speed of Testing A jaw paration of25.4mm[1in] shall be ud.The rate of travel of the power activated grip shall be51mm[2in]/minute and shall be uniform at all times.
7Procedure
7.1Measure the thickness of the specimen at veral points to the accuracy limits of the measuring devices specified in 4.3.Record the average thickness in millimeters or microns [in].
7.2Place the specimen in the grips of the testing machine so that the long axes of the enlarged ends of the specimen are in line with the points of attachment of the grips to the machine.
7.3Apply the load at51mm[2in]/minute rate of grip pa-ration.After complete rupture of the specimen,the maximum tearing load in grams[ounces]shall be noted from the dial scale or recorder chart and recorded.Data from specimens which break at some obvious flaw or which break in or at the edges of the grips shall be discarded and retests made.
8Calculation The average resistance to tearing shall be calculated from five specimens tested in each principal direc-tion of orientation.Data shall be recorded as grams[ounces] of tearing resistance.
9Report
9.1Report the average thickness of all specimens.
9.2Report the average transver and the average longitu-dinal initiation tear strength values.
IPC-TM-650
Number 2.4.16Subject
Initiation Tear Strength,Flexible Insulating Materials
郴州哪里好玩Date
03/14
Revision
B
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