ASTM D648-00a

Standard Test Method for Deflection Temperature of Plastics Under Flexural Load in the Edgewise Position

SCOPE
1.1 This test method covers the determination of the temperature at which an arbitrary deformation occurs when specimens are subjected to an arbitrary set of testing conditions.  
1.2 This test method applies to molded and sheet materials available in thicknesses of 3 mm ( 1/8 in.) or greater and which are rigid at normal temperature.
Note 1—Sheet stock less than 3 mm (0.125 in.) but more than 1 mm (0.040 in.) in thickness may be tested by use of a composite sample having a minimum thickness of 3 mm. The laminae must be of uniform stress distribution. One type of composite specimen has been prepared by cementing the ends of the laminae together and then smoothing the edges with sandpaper. The direction of loading shall be perpendicular to the edges of the individual laminae.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.  
Note 2—The test method described as a Method B of this test method, and test methods Ae and Be of ISO 75-1 and ISO 75-2, 1993 are technically equivalent.

General Information

• Status: Historical
• Publication Date: 09-Aug-2001
• ICS: 83.080.01 - Plastics in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.30 - Thermal Properties

Relations

• Replaced By: ASTM D648-01 - Standard Test Method for Deflection Temperature of Plastics Under Flexural Load in the Edgewise Position
• Effective Date: 10-Aug-2001
• Referred By: ASTM D4216-22 - Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) and Related PVC and Chlorinated Poly(Vinyl Chloride) (CPVC) Building Products Compounds
• Effective Date: 10-Aug-2001
• Referred By: ASTM F3510-21 - Standard Guide for Characterizing Fiber-Based Constructs for Tissue-Engineered Medical Products
• Effective Date: 10-Aug-2001
• Referred By: ASTM F2695-12(2020) - Standard Specification for Ultra-High Molecular Weight Polyethylene Powder Blended With Alpha-Tocopherol (Vitamin E) and Fabricated Forms for Surgical Implant Applications
• Effective Date: 10-Aug-2001
• Referred By: ASTM D635-22 - Standard Test Method for Rate of Burning and/or Extent and Time of Burning of Plastics in a Horizontal Position
• Effective Date: 10-Aug-2001
• Referred By: ASTM D4396-22 - Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) and Chlorinated Poly(Vinyl Chloride) (CPVC) Compounds for Plastic Pipe and Fittings Used in Nonpressure Applications
• Effective Date: 10-Aug-2001
• Referred By: ASTM E2092-18a - Standard Test Method for Distortion Temperature in Three-Point Bending by Thermomechanical Analysis
• Effective Date: 10-Aug-2001
• Referred By: ASTM D6041-23 - Standard Specification for Contact-Molded “Fiberglass” (Glass-Fiber-Reinforced Thermosetting Resin) Corrosion Resistant Pipe and Fittings
• Effective Date: 10-Aug-2001
• Referred By: ASTM D4020-18 - Standard Specification for Ultra-High-Molecular-Weight Polyethylene Molding and Extrusion Materials
• Effective Date: 10-Aug-2001
• Referred By: ASTM D4634-16(2022) - Standard Classification System and Basis for Specification for Styrene-Maleic Anhydride Molding and Extrusion Materials (S/MA)
• Effective Date: 10-Aug-2001
• Referred By: ASTM D5948-05(2020) - Standard Specification for Molding Compounds, Thermosetting
• Effective Date: 10-Aug-2001
• Referred By: ASTM D5364-14(2019) - Standard Guide for Design, Fabrication, and Erection of Fiberglass Reinforced (FRP) Plastic Chimney Liners with Coal-Fired Units
• Effective Date: 10-Aug-2001
• Referred By: ASTM C1349-17 - Standard Specification for Architectural Flat Glass Clad Polycarbonate
• Effective Date: 10-Aug-2001
• Referred By: ASTM D4673-23 - Standard Classification System for and Basis for Specification for Acrylonitrile–Butadiene–Styrene (ABS) Plastics and Alloys Molding and Extrusion Materials
• Effective Date: 10-Aug-2001
• Referred By: ASTM D2609-21 - Standard Specification for Plastic Insert Fittings for Polyethylene (PE) Plastic Pipe
• Effective Date: 10-Aug-2001

Standards Content (Sample)

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.
Designation: D 648 – 00a
Standard Test Method for
Deflection Temperature of Plastics Under Flexural Load in
the Edgewise Position
This standard is issued under the fixed designation D 648; 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 (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.
1. Scope* eters from ISO/IEC Standards
D 5947 Test Methods for Physical Dimensions of Solid
1.1 This test method covers the determination of the tem-
Plastics Specimens
perature at which an arbitrary deformation occurs when speci-
E1 Specification for ASTM Thermometers
mens are subjected to an arbitrary set of testing conditions.
E77 Test Method for Inspection and Verification of Ther-
1.2 This test method applies to molded and sheet materials
mometers
available in thicknesses of 3 mm ( ⁄8 in.) or greater and which
E 177 Practice for Use of the Terms Precision and Bias in
are rigid or semirigid at normal temperature.
ASTM Test Methods
NOTE 1—Sheet stock less than 3 mm (0.125 in.) but more than 1 mm
E 220 Test Method for Calibration of Thermocouples by
(0.040in.)inthicknessmaybetestedbyuseofacompositesamplehaving
Comparison Techniques
a minimum thickness of 3 mm. The laminae must be of uniform stress
E 608 Specification for Metal-Sheathed Base-Metal Ther-
distribution. One type of composite specimen has been prepared by
mocouples
cementing the ends of the laminae together and then smoothing the edges
with sandpaper. The direction of loading shall be perpendicular to the E 644 Test Methods for Testing Industrial Resistance Ther-
edges of the individual laminae.
mometers
E 691 Practice for Conducting an Interlaboratory Study to
1.3 The values stated in SI units are to be regarded as the
Determine the Precision of a Test Method
standard. The values given in parentheses are for information
E 879 Specification for Thermistor Sensors for Clinical
only.
Laboratory Temperature Measurement
1.4 This standard does not purport to address all of the
E 1137 Specification for Industrial Platinum Resistance
safety concerns, if any, associated with its use. It is the
Thermometers
responsibility of the user of this standard to establish appro-
2.2 ISO Standards:
priate safety and health practices and determine the applica-
ISO 75-1 Plastics—Determination of Temperature of De-
bility of regulatory limitations prior to use.
flection Under Load—Part 1: General Test Method
NOTE 2—The test method described as a Method B of this test method,
ISO 75-2 Plastics—Determination of Temperature of De-
and test methods Ae and Be of ISO 75-1 and ISO 75-2, 1993, are
flection Under Load—Part 2: Plastics and Ebonite
technically equivalent.
2.3 NIST Document:
NBS Special Publication 250-22
2. Referenced Documents
2.1 ASTM Standards:
3. Terminology
D 618 Practice for Conditioning Plastics
2 3.1 General—The definitions of plastics used in this test
D 883 Terminology Relating to Plastics
3 method are in accordance with Terminology D 883 unless
D 1898 Practice for Sampling of Plastics
otherwise indicated.
D 1999 Guide for Selection of Specimens and Test Param-
Annual Book of ASTM Standards, Vol 08.03.
1 5
This test method is under the jurisdiction ofASTM Committee D20 on Plastics Annual Book of ASTM Standards, Vol 14.03.
and is the direct responsibility of Subcommittee D20.30 on Thermal Properties Annual Book of ASTM Standards, Vol 14.02.
(Section D20.30.07). Available from American National Standards Institute, 11 W. 42nd St., 13th
Current edition approved Nov. 10, 2000. Published January 2001. Originally Floor, New York, NY 10036.
published as D 648 – 41 T. Last previous edition D 648 – 00 Mangum, B.W., “Platinum ResistanceThermometer Calibration,” NBS Special
Annual Book of ASTM Standards, Vol 08.01. Publication 250-22, 1987. Available from National Institute of Standards and
Discontinued; see 1997 Annual Book of ASTM Standards, Vol 08.01. Technology, Gaithersburg, MD.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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.
D 648 – 00a
4. Summary of Test Method 6. Interferences
6.1 The results of the test may depend on the rate of heat
4.1 A bar of rectangular cross section is tested in the
transfer between the fluid and the specimen and the thermal
edgewise position as a simple beam with the load applied at its
conductivity of the fluid.
center to give maximum fiber stresses of 0.455 MPa (66 psi) or
6.2 The results of this test may depend on the measured
1.82 MPa (264 psi) (Note 3). The specimen is immersed under
width and depth of the specimen and the final deflection at
load in a heat-transfer medium provided with a means of
which the deflection temperature is determined.
raising the temperature at 2 6 0.2°C/min. The temperature of
6.3 The type of mold and the molding process used to
the medium is measured when the test bar has deflected 0.25
produce test specimens affects the results obtained in this test.
mm (0.010 in.). This temperature is recorded as the deflection
Molding conditions shall be in accordance with the standard
temperature under flexural load of the test specimen.
for that material or shall be agreed upon by the cooperating
laboratories.
NOTE 3—Aroundrobinhasbeenconductedthatshowedthatthereisno
advantagetousinghigherloadswhenmeasuringdeflectiontemperatureof
present-day plastics with present-day instruments.
7. Apparatus
7.1 The apparatus shall be constructed essentially as shown
5. Significance and Use
in Fig. 1 and shall consist of the following:
5.1 This test is particularly suited to control and develop-
7.1.1 Specimen Supports, metal supports, allowing the load
ment work. Data obtained by this test method may not be used
to be applied on top of the specimen vertically and midway
to predict the behavior of plastic materials at elevated tempera-
between the supports, which shall be separated by a distance,
tures except in applications in which the factors of time,
defined in 7.1.1.1 or 7.1.1.2. The contact edges of the supports
temperature, method of loading, and fiber stress are similar to and of the piece by which load is applied shall be rounded to
those specified in this test method. The data are not intended a radius of 3 6 0.2 mm (0.118 6 0.008 in.).
for use in design or predicting endurance at elevated tempera- 7.1.1.1 Method A—101.6 6 0.5 mm (4.0 6 0.02 in.).
tures. 7.1.1.2 Method B—100.0 6 0.5 mm (3.937 6 0.020 in.).
FIG. 1 Apparatus for Deflection Temperature Test
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.
D 648 – 00a
NOTE 4—Atestshouldbemadeoneachapparatususingatestbarmade
m = mass of the rod that applies the testing force to the
r
of a material having a low coefficient of expansion. The temperature
specimen, kg.
range to be used should be covered and a correction factor determined for
each temperature. If this factor is 0.013 mm (0.0005 in.) or greater, its
NOTE 7—In some designs of this apparatus, the spring force of the dial
algebraicsignshouldbenotedandthefactorshouldbeappliedtoeachtest
gage is directed upward (opposite the direction of specimen loading,)
by adding it algebraically to the reading of apparent deflection of the test
which reduces the net force applied to the specimen. In other designs, the
specimen.
spring force of the dial gage acts downward (in the direction of specimen
loading), which increases the net force applies to the specimen. The mass
7.1.2 Immersion Bath—A suitable liquid heat-transfer me-
applied to the loading rod must be adjusted accordingly (increased for
dium (Note 5) in which the specimen shall be immersed. It
upward dial force and decreased for downward dial force) to compensate.
shall be well-stirred during the test and shall be provided with
Since the force exerted by the spring in certain dial gages varies
a means of raising the temperature at a uniform rate of 2 6
considerably over the stroke, this force should be measured in that part of
the stroke that is to be used. Suggested procedures to determine the total
0.2°C/min. This heating rate shall be considered to be met if,
load required to correct for the force of the dial gage spring are given in
overevery5-minintervalduringthetest,thetemperatureofthe
Appendix X1 and Appendix X2. Other procedures may be used if
bath shall rise 10 6 1°C at each specimen location.
equivalent results are obtained. Appendix X3 provides a method of
NOTE 5—Aliquid heat-transfer medium shall be chosen which will not determining the spring force, uniformity of the force in the gage’s test
affect the specimen. Mineral oil is considered safe from ignition to 115°C. measurement range, and whether the gage is contaminated and sticking.
Silicone oils may be heated to about 260°C for short periods of time. For
7.1.5 Temperature Measurement System—Consisting of a
still higher temperatures, special heat-transfer media should be used.
thermocouple, thermometer, resistance thermometer, ther-
Improved performance with longer oil life may be obtained by the use of
mistor, etc., as the sensor, together with its associated condi-
CO or other inert gas to isolate the oil surface from the atmosphere.
tioning and readout instrumentation to cover a suitable range.
NOTE 6—A circulating air oven may be used if it can be shown that
equivalent results are obtained. The thermometer shall be one of the following, or its equiva-
lent, as prescribed in Specification E1: Thermometer 1°C or
7.1.3 Deflection Measurement Device, suitable for measur-
2°C, having ranges from –20 to 150°C or –5 to 300°C
ing specimen deflection of at least 0.25 mm (0.010 in.). It shall
respectively, whichever temperature range is most suitable.
be readable to 0.01 mm (0.0005 in.) or better. The device may
Mercuryinglassthermometersshallbecalibratedforthedepth
be a dial gage or any other indicating or recording device
of immersion in accordance with Test MethodE77. Thermo-
including electric displacement sensing apparatus.
couples shall comply with the requirements of Specification
7.1.4 Weights—Aset of weights of suitable sizes so that the
E 608. Thermocouples shall be calibrated in accordance with
specimen can be loaded to a fiber stress of 0.455 MPa (66 psi)
Test Method E 220. Resistance thermometers shall comply
6 2.5 % or 1.82 MPa (264 psi) 6 2.5 %. The mass of the rod
with the requirements ofTest Methods E 644 and Specification
that applies the testing force shall be determined and included
E 1137. Thermistors shall comply with the requirements of
as part of the total load. If a dial gage is used, the force exerted
Specification E 879 and be calibrated in accordance with NIST
by its spring shall be determined and shall be included as part
Special Publication 250-22.
of the load (Note 8). Calculate the testing force and the mass
7.2 Micrometers shall meet the requirements of Test Meth-
that must be added to achieve the desired stress as follows:
ods D 5947 and be calibrated in accordance with that test
F 5 2Sbd /3L (1)
method.
F 5 F/9.80665
8. Sampling
m 5 ~F – F !/9.80665 – m
w s r
8.1 Unless otherwise specified, sampling shall be in accor-
where:
dance with the sampling procedure prescribed in Practice
F = load, N,
D 1898. Adequate statistical sampling shall be considered an
F = load, kgf,
acceptable alternative.
S = fiber stress in the specimen (0.455 MPa or 1.82
MPa),
9. Test Specimen
b = width of specimen, mm,
9.1 At least two test specimens shall be used to test each
d = depth of specimen, mm,
sample at each fiber stress. The specimen shall be 127 mm (5
L = distance between supports, (101.6 mm—Method A,
in.) in length, 13 mm ( ⁄2 in.) in depth by any width from 3 mm
or 100 mm—Method B), see 7.1.1.1 and 7.1.1.2.
1 1
( ⁄8in.)to13mm( ⁄2in.).Tolerancesondimensions(forhighly
m = added mass, kg,
w
reproducible work) should be of the order of 60.13 mm (0.005
F = force exerted by any spring-loaded component in-
s
in.) over the length of the specimen.
volved, N; this is a positive value if the thrust of the
spring is towards the test specimen (downwards), or
NOTE 8—The test results obtained on specimens approaching 13 mm in
anegativevalueifthethrustofthespringisopposing width may be 2 to 4°C above those obtained from 4 mm or narrower test
specimens because of poor heat transfer through the specimen.
the descent of the rod, or zero if no such component
is involved, and
9.2 The specimens shall have smooth flat surfaces free from
saw cuts, excessive sink marks, or flash.
9.3 Molding conditions shall be in accordance with the
specification for that material or shall be agreed upon by the
Invar or borosilicate glass have been found suitable for this purpose. cooperating laboratories. Discrepancies in test results due to
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.
D 648 – 00a
variations in molding conditions may be minimized by anneal- 12.3 The thermometer bulb or sensitive part of the tempera-
ing the test specimens before the test. Since different materials ture measuring device shall be positioned as close as possible
require different annealing conditions, annealing procedures to the test specimen (within 10 mm) without touching it. The
shall be employed only if required by the material standard or stirring of the liquid-heat transfer medium shall be sufficient to
if agreed upon by the cooperating laboratories. ensure that temperature of the medium is within 1.0°C at any
point within 10 mm of the specimen. If stirring is not sufficient
10. Preparation of Apparatus
to meet the 1.0°C requirement, then the temperature measuring
device shall be placed at the same level as the specimen and
10.1 The apparatus shall be arranged so that the deflection
within 10 mm of the point at which the specimen is loaded.
of the specimen at midspan is measured by the deflection
12.4 Ascertain that the temperature of the bath is suitable.
measurement device described in 7.1.3. The apparatus may be
The bath temperature shall be at ambient temperature at the
arranged to shut off the
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