ASTM F1293-91A

Test Method for Evaluation of Coated Transparent Plastics Subjected to Cyclic Flexural/Thermal Fatigue (Withdrawn 2000)

SCOPE
1.1 This test method defines a procedure for evaluating the craze resistance of coated transparent plastics subjected to cyclic bending stresses induced by pressurizing the specimen under ambient, hot, and cold temperature conditions.
1.2 This standard does not purport to address all of the safety problems, 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.  
1.3 The values stated in SI units are to be regarded as the standard.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1990
• Withdrawal Date: 09-Oct-2000
• ICS: 83.140.01 - Rubber and plastics products in general
• Technical Committee: F07 - Aerospace and Aircraft
• Drafting Committee: F07.08 - Transparent Enclosures and Materials

Standards Content (Sample)

ASTM FI1293 REV*A 93
0759530 0530679 OT2
(@ Designation: F 1293 - 91a
Standard lest Method for
Evaluation of Coated Transparent Plastics Subjected to Cyclic
Flexural/Thermal Fatigue'
This standard is issued under the fixed designation F 1293; 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.
coatings on transparent plastics prior to in-service exposure,
1. Scope
taking into account the influence of biaxial bending stress
1.1 This test method defines a procedure for evaluating
combined with ambient, elevated, and low temperature.
the craze resistance of coated transparent plastics subjected
to cyclic bending stresses induced by pressurizing the spec-
6. Apparatus
imen under ambient, hot, and cold temperature conditions.
6.1 Manifold Test Fixture-The pressure-cell/test-fixture
1.2 This standard does not purport to address all of the
used to flex the specimen is detailed in Test Method F 1164.
safety problems, if any, associated with its use. It is the
Safety precautions should be taken to depressurize the test
responsibility of the user of this standard to establish appro-
fixture prior to handling, removing, or changing specimens
priate safety and health practices and determine the applica-
or servicing the heating/cooling chamber, or a combination
bility of regulatory limitations prior to use.
thereof.
1.3 The values stated in SI units are to be regarded as the
6.2 Heating/Cooling Chamber-Details of design and
standard.
construction of a high/low temperature test chamber are
optional. However, the following general guidelines should
2. Referenced Document
be implemented to satisfy essential requirements.
2.1 ASTM Standards:
6.2.1 Use insulated construction.
F 1164 Test Method for Evaluation of Transparent Plas-
6.2.2 The cabinet shall be cooled using expendable refrig-
tics Exposed to Accelerated Weathering Combined with
erant, either liquid nitrogen vapor or liquid carbon dioxide
Biaxial Stress.2
vapor, and heated using clean air.
6.2.3 Thermocouples are satisfactory for measuring tem-
3. Terminology
perature. Control the maximum test temperature fluctuation
3.1 Description of Term Specijìc to This Standard: inside the cabinet to +4"C (7°F) within 2 in. distant from the
3.1. I crazing-fine cracks, sometimes hairline in size, test surface midpoint of each specimen.
which may extend in a network in or under the surface or
7. Test Specimens
through a plastic.
7.1 Use at least three coated specimens for each coating
4. Summary of Test Method being tested. The specimen configuration shall be as follows:
clean, coated, transparent circular plates, 21 6 mm (8.50 in.)
4.1 This test method consists of mounting an unexposed
in diameter, having both sides substantially plane and
circular plate test specimen in the test apparatus; subjecting
parallel; coated specimen nominal thickness being 5 m (0.20
the specimen to alternating cycles of pressure and tempera-
in.).
ture; and periodically inspecting for evidence of crazing on
the coated surface of the specimen.
8. Test Conditions
8.1 Conduct tests in the laboratory atmosphere of 23 f
5. Significance and Use
2°C (73.4 -i- 3.6"F) and 50 -i- 5 % relative humidity unless
5.1 Many coated transparent plastics, such as acrylic and
otherwise specified.
polycarbonate commercial aircraft cabin windows and mili-
tary aircraft canopies having abrasion resistant surface coat-
9. Procedure
ings, are exposed to significant flexing and temperature
9.1 Code mark each specimen and circumferentially
changes during flight. These factors influence the initiation
clamp specimen in the manifold test fixture using 2.825 J (25
of surface crazing, leading to further optical degradation, and
in-lb) bolt torque. The outer tensile test/exposure side of
finally to in-service removal and replacement. This test
each specimen shall be the coated surface.
method provides the transparency suppliers and users with a
9.2 In accordance with Test Method F 1 164, calibrate or
realistic screening test to assess the long-term performance of
calculate the required pressure to induce an outer coated
surface (tensile) strain 13.8 x lo6 (l-v)/E m/m in metric
units (2000 (1-v)/E in./in. in inch pound units in the center
'This test method is under the jurisdiction of ASTM Committee F-7 on
Aerospace and Aircrafi and is the direct responsibility of Subcommittee F07.08 on
of the specimen, where Y = Poisson's ratio at room temper-
Transparent Enclosures and Materials.
ature and E = modulus of elasticity (Pa or psi) at room
Current edition approved Dec. 15, 1991. Published February 1992. Originally
temperature for the test material.
published as F I293 - 9 I. iast previous edition
...