ASTM D6343-99(2004)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
An American National Standard
Designation:D6343–99 (Reapproved 2004)
Standard Test Methods for
Thin Thermally Conductive Solid Materials for Electrical
Insulation and Dielectric Applications
This standard is issued under the fixed designation D6343; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope mittivity (Dielectric Constant) of Solid Electrical Insula-
tion
1.1 This standard is a compilation of test methods for
D257 Test Methods for DC Resistance or Conductance of
evaluating properties of thermally conductive electrical insu-
Insulating Materials
lation sheet materials to be used for dielectric applications.
D374M Test Methods for Thickness of Solid Electrical
1.2 Such materials are thin, compliant sheets, typically
Insulation (Metric)
produced by mixing thermally conductive particulate fillers
D412 Test Methods for Vulcanized Rubber and Thermo-
with organic or silicone binders. For added physical strength
plastic Elastomers—Tension
these materials are often reinforced with a woven or nonwoven
D624 Test Method for Tear Strength of Conventional Vul-
fabric or a dielectric film.
canized Rubber and Thermoplastic Elastomers
1.3 These test methods apply to thermally conductive sheet
D792 Test Methods for Density and Specific Gravity (Rela-
material ranging from about 0.02 to 6-mm thickness.
tive Density) of Plastics by Displacement
1.4 This standard does not purport to address all of the
D883 Terminology Relating to Plastics
safety concerns, if any, associated with its use. It is the
D1000 Test Methods for Pressure-Sensitive Adhesive-
responsibility of the user of this standard to establish appro-
Coated Tapes Used for Electrical and Electronic Applica-
priate safety and health practices and determine the applica-
tions
bility of regulatory limitations prior to use. See also 18.1.2 and
D1458 Test Methods for Fully Cured Silicone Rubber-
19.1.2.
Coated Glass Fabric and Tapes for Electrical Insulation
1.5 The values stated in SI units are to be regarded as
D1711 Terminology Relating to Electrical Insulation
standard.
D2240 Test Method for Rubber Property—Durometer
NOTE 1—ThereisnoIECpublicationorISOstandardequivalenttothis
Hardness
standard.
D5470 Test Method forThermalTransmission Properties of
Thermally Conductive Electrical Insulation Materials
2. Referenced Documents
D6054 Practice for Conditioning Electrical Insulating Ma-
2.1 ASTM Standards:
terials for Testing
D149 Test Method for Dielectric Breakdown Voltage and
Dielectric Strength of Solid Electrical Insulating Materials
3. Terminology
at Commercial Power Frequencies
3.1 Definitions of Terms Specific to This Standard:
D150 Test Methods for AC Loss Characteristics and Per-
3.1.1 apparent thermal conductivity, n—the time rate of
heat flow, under steady conditions, through unit area, per unit
temperature gradient in the direction perpendicular to the area,
These test methods are under the jurisdiction of ASTM Committee D09 on for a nonhomogeneous material.
Electrical and Electronic Insulating Materials and are the direct responsibility of
3.1.1.1 See 16.1 for a discussion of the terms thermal
Subcommittee D09.19 on Dielectric Sheet and Roll Products.
conductivity and apparent thermal conductivity. To avoid
Current edition approved March 10, 1999. Published June 1999. Originally
confusion, these test methods use apparent thermal conductiv-
approved in 1998. Last previous edition approved in 1998 as D6343 – 98. DOI:
10.1520/D6343-99R04.
ity for measurements of homogeneous and nonhomogeneous
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
materials.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3.1.2 See Terminologies D1711 and D883 for definitions of
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. other terms used in these test methods.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6343–99 (2004)
4. Significance and Use on one or both sides. In some cases performance in a particular
application can be affected by the adhesion strength.
4.1 These test methods are useful to determine compliance
9.2 Procedure—Test three specimens of 25-mm width in
of thermally conductive sheet electrical insulation with speci-
accordance with Test Methods D1000 except, clean the steel
fication requirements established jointly by a producer and a
panel with isopropyl alcohol.
user.
9.3 Calculation—From the 3 specimens, calculate the aver-
4.2 These test methods have been found useful for quality
assessment. Results of the test methods can be useful in age adhesion strength.
apparatus design.
9.4 Report—Report the average adhesion strength in new-
tons per metre of width.
5. Specimen Preparation
5.1 From a sample of sufficient size, prepare test specimens
10. Breaking Strength
of the dimensions and of the quantity to meet the requirements
10.1 Significance and Use—Breaking strength can be a
for each test procedure.
significant limitation on methods of applying tapes. Hence it
may be important to measure the tensile force they can
6. Conditioning
withstand.
6.1 Unless otherwise specified, condition specimens in ac-
10.2 Procedure:
cordancewithProcedureAofPracticeD6054.Performalltests
10.2.1 Prepare three specimens at least 500 mm long and 25
on specimens that are in equilibrium with the conditions of
mmwide.Ifthematerialcontainsreinforcingfibers,cutthetest
Procedure A of Practice D6054. Make the tests in a chamber
specimen such that the machine direction reinforcing fibers are
maintained at 23 6 2 °C and 50 6 5 % relative humidity.
parallel to the long axis of the specimen. In the case of
6.2 When required by a test procedure, condition specimens
materials narrower than 25 mm, test the full width as received.
in accordance with Procedure D of Practice D6054 except that
10.2.2 Test the breaking strength in accordance with Test
either distilled or deionized water may be used. In such cases,
Methods D1458.
remove the specimens from the water into air maintained at 23
10.3 Calculation—From the test measurements on the 3
6 2 °C and 50 6 5 % relative humidity, remove surface water
specimens, calculate the average breaking strength.
with a paper towel, and begin testing within 30 s.
10.4 Report—Report the average breaking strength in new-
7. Precision and Bias
tons per metre of width.
7.1 No evaluation of precision or bias has been established
forthetestmethodshereinastheyrelatetothesethinthermally 11. Tensile Strength and Elongation
conductivematerials.Forgeneralguidanceonly,referencemay
11.1 Significance and Use—Tensile test results with these
be made to Precision and Bias statements in the referenced test
materials will vary with specimen geometry and conditions of
methods as listed in Section 2.
testing. Hence, these tensile measurements are not always
reliable indicators of usefulness in a particular application.
8. Thickness
Tensile properties of glass-fiber-reinforced materials vary with
8.1 Significance and Use—The accurate determination of
the ratio of the glass-fiber thickness to the total thickness.
thickness is essential for design purposes for both thermal
Measurements of tensile properties vary with the direction of
conduction and electrical insulation. Thickness enters into the
the glass fibers with respect to the direction in which the
calculation of thermal, electrical, and tensile properties.
specimen is cut.
8.2 Procedure:
11.2 Procedure:
8.2.1 Make thickness measurements on specimens in accor-
11.2.1 Prepare three specimens in accordance with Test
dance with Test Methods D374M, Method H. This test method
Methods D412 using Die C.
uses a micrometer which applies a pressure of 26 6 4 kPa on
11.2.2 If the material contains reinforcing fibers, cut the test
the specimen, using a 6.25-mm diameter presser foot.
specimensuchthatanyreinforcingfibersareat45 610°tothe
8.2.2 Clean the surfaces where the measurements are to be
long axis of the specimen.
made. Take five randomly spaced measurements to cover the
11.2.3 In accordance with Test Methods D412, measure the
length and width of the specimen. Take measurements at least
tensile breaking strength and tensile elongation at a jaw
6 mm from the edges of the specimen.
separation rate of 500 mm/min (20 in./min).
NOTE 2—At the compressive loads of this test method, some materials
11.3 Calculation:
will undergo compression or compression deflection. The buyer and the
seller may wish to agree on other conditions of pressure, anvil and presser 11.3.1 Calculate the tensile strength in kilopascals using the
foot geometry, and the dwell time to be used.
initial thickness and width for each specimen. Calculate the
average tensile strength from the three test measurements.
8.3 Report—Report the thickness in millimetres as the
11.3.2 Similarly, calculate each elongation at break as a
average of the five measurements.
percentage of the initial jaw separation. Calculate the average
9. Adhesion Strength
from the three test measurements.
9.1 Significance and Use—Materials covered by this test 11.4 Report—Report the average tensile strength in kilopas-
methodareoptionallycoatedwithapressuresensitiveadhesive cals and the average elongation in percent.
D6343–99 (2004)
12. Hardness tics of a material under a specific set of conditions, it is not
appropriate to use these results to predict performance in an
12.1 Significance and Use—This test method is empirical
application where conditions differ from those of the test.
and intended for control purposes only.
15.2 Procedure:
12.2 Procedure:
15.2.1 Prepare specimens for two determinations as re-
12.2.1 Prepare a sufficient number of specimens to form a
quiredbyeitherMethodAorMethodBofTestMethodD5470.
stack approximately 6 mm high.
15.2.2 Measure the thermal impedance in accordance with
12.2.2 Determine the indentation hardness in accordance
Test Method D5470, using a pressure of 3.0 6 0.1 MPa and an
with Test Method D2240 with the following exception:
average specimen temperature of 50 6 5°C.
12.2.2.1 Read the scale within 2 s after the presser foot is in
15.3 Calculation—From the two determinations, calculate
firm contact with the specimen.
the average thermal impedance.
12.3 Calculation—From the five measurements taken at
15.4 Report—Report the average thermal impedance in
diffe
...