ASTM F736-95(2011)

Standard Test Method for Impact Resistance of Monolithic Polycarbonate Sheet by Means of a Falling Weight

SIGNIFICANCE AND USE
This practice is applicable for qualitatively evaluating coated and uncoated monolithic polycarbonate sheet material, for monitoring process control, for screening studies, and as an aid in the prediction of hardware performance when exposed to impact service conditions.
A limitation of Type A specimen testing is that a thick sheet may not fail since the available impact energy is limited by the maximum drop height and falling weight capacity of the test apparatus. Use Specimen Type A for material less than 12.7 mm (0.50 in.) thick.
Within the range of drop heights of this system, tests employing different velocities are not expected to produce different results. However, for a given series of tests, it is recommended that the drop height be held approximately constant so that velocity of impact (strain rate) will not be a variable.
As the polycarbonate specimen undergoes large plastic deformation under impact, the down (opposite impact) side is under tensile loading and most influential in initiating failure. Polycarbonate sheet coated on one side may yield significantly different test results when tested with the coated side down versus the coated side up.
Direct comparison of specimen Type A and specimen Type B test results should not be attempted. For test programs that will require the comparison of interlaboratory test results the specimen type and the approximate drop height must be specified.
Monolithic polycarbonate sheet is notch sensitive. Data obtained from other test methods, particularly notched Izod/Charpy test results, and extremely high- or low-strain rate test results, should not be compared directly to data obtained from this method. It is noted that Type A specimens, free of flaws, have not experienced the characteristic ductile-to-brittle transition between thin, less than 3.18 mm (1/8 in.), and thick, greater than 7.94 mm (5/16 in.), sheet as reflected by other test methods.
SCOPE
1.1 This test method covers the determination of the energy required to initiate failure in monolithic polycarbonate sheet material under specified conditions of impact using a free falling weight.
1.2 Two specimen types are defined as follows:
1.2.1 Type A consists of a flat plate test specimen and employs a clamped ring support.
1.2.2 Type B consists of a simply supported three-point loaded beam specimen (Fig. 1) and is recommended for use with material which can not be failed using the Type A specimen. For a maximum drop height of 6.096 m (20 ft) and a maximum drop weight of 22.68 kg (50 lb), virgin polycarbonate greater than 12.70 mm (½ in.) thick will probably require use of the Type B specimen.
Note 1—See also ASTM Methods: D1709, D2444 and D3029.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3.1 Exception—The inch-pound units in parentheses are provided 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. For specific hazard statement, See Section 7.
FIG. 1 Type B Specimen Geometry and Loading

General Information

• Status: Historical
• Publication Date: 30-Nov-2011
• ICS: 83.140.10 - Films and sheets
• Technical Committee: F07 - Aerospace and Aircraft
• Drafting Committee: F07.08 - Transparent Enclosures and Materials

Relations

• Replaces: ASTM F736-95(2006) - Standard Test Method for Impact Resistance of Monolithic Polycarbonate Sheet by Means of a Falling Weight
• Effective Date: 01-Dec-2011
• Referred By: ASTM F790-23 - Standard Guide for Testing Materials for Aerospace Plastic Transparent Enclosures
• Effective Date: 01-Dec-2011

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: F736 − 95 (Reapproved 2011)
Standard Test Method for
Impact Resistance of Monolithic Polycarbonate Sheet by
Means of a Falling Weight
ThisstandardisissuedunderthefixeddesignationF736;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope D790 Test Methods for Flexural Properties of Unreinforced
and Reinforced Plastics and Electrical Insulating Materi-
1.1 This test method covers the determination of the energy
als
required to initiate failure in monolithic polycarbonate sheet
material under specified conditions of impact using a free
3. Terminology
falling weight.
3.1 Definitions of Terms Specific to This Standard:
1.2 Two specimen types are defined as follows:
3.1.1 failure (of test specimen)—failure is signified by the
1.2.1 Type A consists of a flat plate test specimen and
presence of any crack or split in the impact-deformed area that
employs a clamped ring support.
was created by the impact of the falling weight and that can be
1.2.2 Type B consists of a simply supported three-point
seen by the naked eye.
loaded beam specimen (Fig. 1) and is recommended for use
with material which can not be failed using the Type A
4. Summary of Test Method
specimen. For a maximum drop height of 6.096 m (20 ft) and
4.1 The test procedure to cause failure covers a range of
a maximum drop weight of 22.68 kg (50 lb), virgin polycar-
impact energies and differs with respect to geometry and
bonate greater than 12.70 mm ( ⁄2 in.) thick will probably
support of test specimen Type A and test specimen Type B.
require use of the Type B specimen.
Guidelines are established to control drop heights, impact
NOTE 1—See also ASTM Methods: D1709, D2444 and D3029.
velocity, drop weights, impactor heads, impactor release,
1.3 The values stated in SI units are to be regarded as
impactorrebound,impactlocation,andspecimenconfiguration
standard. No other units of measurement are included in this
which are applicable to a falling weight impact tester designed
standard.
to accommodate Type A or Type B test specimens, or both,
1.3.1 Exception—The inch-pound units in parentheses are
fabricated from monolithic polycarbonate sheet material.
provided for information only.
5. Significance and Use
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
5.1 This practice is applicable for qualitatively evaluating
responsibility of the user of this standard to establish appro-
coated and uncoated monolithic polycarbonate sheet material,
priate safety and health practices and determine the applica-
for monitoring process control, for screening studies, and as an
bility of regulatory limitations prior to use. For specific hazard
aidinthepredictionofhardwareperformancewhenexposedto
statement, See Section 7.
impact service conditions.
5.2 A limitation of Type A specimen testing is that a thick
2. Referenced Documents
sheet may not fail since the available impact energy is limited
2.1 ASTM Standards:
by the maximum drop height and falling weight capacity of the
D618 Practice for Conditioning Plastics for Testing
testapparatus.UseSpecimenTypeAformateriallessthan12.7
mm (0.50 in.) thick.
5.3 Within the range of drop heights of this system, tests
This test method is under the jurisdiction of ASTM Committee F07 on
employing different velocities are not expected to produce
Aerospace and Aircraft and is the direct responsibility of Subcommittee F07.08 on
Transparent Enclosures and Materials.
different results. However, for a given series of tests, it is
Current edition approved Dec. 1, 2011. Published April 2012. Originally
recommended that the drop height be held approximately
approved in 1981. Last previous edition approved in 2006 as F736 – 95 (2006).
constant so that velocity of impact (strain rate) will not be a
DOI: 10.1520/F0736-95R11.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or variable.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
5.4 As the polycarbonate specimen undergoes large plastic
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. deformation under impact, the down (opposite impact) side is
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F736 − 95 (2011)
FIG. 1 Type B Specimen Geometry and Loading
under tensile loading and most influential in initiating failure. surface irregularities. The impactor geometry for Type B
Polycarbonate sheet coated on one side may yield significantly specimens corresponds to Test Method D790.
different test results when tested with the coated side down 6.1.4 Impact Location—The center of mass of the falling
versus the coated side up. weight shall be guided by a two cable system or other suitable
means to repeatedly strike within 2.54 mm (0.10 in.) of the
5.5 Direct comparison of specimen Type A and specimen
center of the specimen support fixture as measured in the plane
Type B test results should not be attempted. For test programs
of the specimen, in order to assure uniform, reproducible
that will require the comparison of interlaboratory test results
drops. Friction retarding the falling weight should be minimal
the specimen type and the approximate drop height must be
so that the impact velocity approaches
specified.
=2gh
5.6 Monolithic polycarbonate sheet is notch sensitive. Data
obtained from other test methods, particularly notched Izod/
where:
Charpy test results, and extremely high- or low-strain rate test
g = acceleration of gravity, and
results, should not be compared directly to data obtained from
h = drop height.
this method. It is noted that Type A specimens, free of flaws,
6.1.5 Supports—Clamp and support rings as shown inFig. 5
have not experienced the characteristic ductile-to-brittle tran-
and Table 1 will be used to accommodate Type A plate
sition between thin, less than 3.18 mm ( ⁄8 in.), and thick,
specimens. Adjustable D790–Test Method 1 supports will be
greater than 7.94 mm ( ⁄16 in.), sheet as reflected by other test
used to accommodate the Type B simply supported beam
methods.
specimens of 6 + 1 span-to-depth ratio. Specimens shall be
6. Apparatus
supported so that the surface to be impacted is horizontal and
at an angle of 90 (6 1)° (π/2 radians) with respect to the falling
6.1 Impact Tester—The apparatus shall be constructed es-
weight guides.
sentially as shown in Fig. 2. Although not specified, materials
called out have been found to be satisfactory.
6.1.1 Drop Height—A lifting carrier shall be provided to
raise or lower the falling weight impactor that will be adjust-
TABLE 1 Plate Support Ring Geometry
ablewithintherangeof0.305m(1ft)tomaximumdropheight
NOTE 1—Reference Fig. 5 for definition of “A” and “C.”
and measurable to the nearest 25.40 mm (1 in.).
Ring Size “A”“C” Span
6.1.2 Drop Weight—Thefallingweightsshallbedetachable,
mm (in.) mm (in.) mm (in.)
interchangeable, and variable in small known increments from
1 88.9 (3.50) 127.0 (5.00) 101.6 (4.00)
a total of 0.45 kg (1 lb) to a maximum drop weight of 50 kg
2 114.3 (4.50) 157.5 (6.20) 127.0 (5.00)
(110 lb).
3 190.5 (7.50) 254.0 (10.00) 203.2 (8.00)
4 292.1 (11.50) 381.0 (15.00) 304.8 (12.00)
6.1.3 Impactor—The loading nose to be used with Type A
specimens is shown inFig. 3; withType B specimens as shown
in Fig. 4. The impactor surface shall be free of nicks or other
F736 − 95 (2011)
FIG. 2 Falling Weight Impact Tester
6.
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:F736–95 (Reapproved 2006)
Standard Test Method for
Impact Resistance of Monolithic Polycarbonate Sheet by
Means of a Falling Weight
ThisstandardisissuedunderthefixeddesignationF736;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the determination of the energy required to initiate failure in monolithic polycarbonate sheet
material under specified conditions of impact using a free falling weight.
1.2 Two specimen types are defined as follows:
1.2.1 Type A consists of a flat plate test specimen and employs a clamped ring support.
1.2.2 Type B consists of a simply supported three-point loaded beam specimen (Fig. 1) and is recommended for use with
material which can not be failed using the TypeAspecimen. For a maximum drop height of 6.096 m (20 ft) and a maximum drop
weight of 22.68 kg (50 lb), virgin polycarbonate greater than 12.70 mm ( ⁄2 in.) thick will probably require use of the Type B
specimen.
NOTE 1—See also ASTM Methods: D1709, D2444 and D3029.
1.3 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. For specific hazard statement, See Section 7.
2. Referenced Documents
2.1 ASTM Standards:
D618 Practice for Conditioning Plastics for Testing
D790 Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 failure (of test specimen)—failure is signified by the presence of any crack or split in the impact-deformed area that was
created by the impact of the falling weight and that can be seen by the naked eye.
4. Summary of Test Method
4.1 The test procedure to cause failure covers a range of impact energies and differs with respect to geometry and support of
test specimen TypeAand test specimen Type B. Guidelines are established to control drop heights, impact velocity, drop weights,
impactor heads, impactor release, impactor rebound, impact location, and specimen configuration which are applicable to a falling
weightimpacttesterdesignedtoaccommodateTypeAorTypeBtestspecimens,orboth,fabricatedfrommonolithicpolycarbonate
sheet material.
5. Significance and Use
5.1 This practice is applicable for qualitatively evaluating coated and uncoated monolithic polycarbonate sheet material, for
monitoring process control, for screening studies, and as an aid in the prediction of hardware performance when exposed to impact
service conditions.
5.2 A limitation of Type A specimen testing is that a thick sheet may not fail since the available impact energy is limited by
the maximum drop height and falling weight capacity of the test apparatus. Use Specimen TypeAfor material less than 12.7 mm
(0.50 in.) thick.
This test method is under the jurisdiction of ASTM Committee F07 on Aerospace and Aircraft and is the direct responsibility of Subcommittee F07.08 on Transparent
Enclosures and Materials.
Current edition approved Nov. 1, 2006. Published January 2007. Originally approved in 1981. Last previous edition approved in 2001 as F736 – 95 (2001). DOI:
10.1520/F0736-95R06.
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F736–95 (2006)
FIG. 1 Type B Specimen Geometry and Loading
5.3 Within the range of drop heights of this system, tests employing different velocities are not expected to produce different
results. However, for a given series of tests, it is recommended that the drop height be held approximately constant so that velocity
of impact (strain rate) will not be a variable.
5.4 As the polycarbonate specimen undergoes large plastic deformation under impact, the down (opposite impact) side is under
tensile loading and most influential in initiating failure. Polycarbonate sheet coated on one side may yield significantly different
test results when tested with the coated side down versus the coated side up.
5.5 Direct comparison of specimen Type A and specimen Type B test results should not be attempted. For test programs that
will require the comparison of interlaboratory test results the specimen type and the approximate drop height must be specified.
5.6 Monolithic polycarbonate sheet is notch sensitive. Data obtained from other test methods, particularly notched Izod/Charpy
test results, and extremely high- or low-strain rate test results, should not be compared directly to data obtained from this method.
It is noted that Type A specimens, free of flaws, have not experienced the characteristic ductile-to-brittle transition between thin,
1 5
less than 3.18 mm ( ⁄8 in.), and thick, greater than 7.94 mm ( ⁄16 in.), sheet as reflected by other test methods.
6. Apparatus
6.1 Impact Tester—The apparatus shall be constructed essentially as shown in Fig. 2. Although not specified, materials called
out have been found to be satisfactory.
6.1.1 Drop Height—Aliftingcarriershallbeprovidedtoraiseorlowerthefallingweightimpactorthatwillbeadjustablewithin
the range of 0.305 m (1 ft) to maximum drop height and measurable to the nearest 25.40 mm (1 in.).
6.1.2 Drop Weight—The falling weights shall be detachable, interchangeable, and variable in small known increments from a
total of 0.45 kg (1 lb) to a maximum drop weight of 50 kg (110 lb).
6.1.3 Impactor—The loading nose to be used with Type A specimens is shown in Fig. 3; with Type B specimens as shown in
Fig. 4. The impactor surface shall be free of nicks or other surface irregularities. The impactor geometry for Type B specimens
corresponds to Test Method D790.
6.1.4 Impact Location—The center of mass of the falling weight shall be guided by a two cable system or other suitable means
to repeatedly strike within 2.54 mm (0.10 in.) of the center of the specimen support fixture as measured in the plane of the
specimen,inordertoassureuniform,reproducibledrops.Frictionretardingthefallingweightshouldbeminimalsothattheimpact
velocity approaches
=2gh
where:
g = acceleration of gravity, and
h = drop height.
6.1.5 Supports—Clamp and support rings as shown in Fig. 5 andTable 1 will be used to accommodateTypeAplate specimens.
Adjustable D790–Test Method 1 supports will be used to accommodate the Type B simply supported beam specimens of 6 + 1
span-to-depth ratio. Specimens shall be supported so that the surface to be impacted is horizontal and at an angle of 90 (6 1)° (p/2
radians) with respect to the falling weight guides.
F736–95 (2006)
FIG. 2 Falling Weight Impact Tester
TABLE 1 Plate Support Ring Geometry
NOTE 1—Reference Fig. 5 for definition of “A” and “C.”
Ring Size “A”“C” Span
mm (in.) mm (in.) mm (in.)
1 88.9 (3.50) 127.0 (5.00) 101.6 (4.00)
2 114.3 (4.50) 157.5 (6.20) 127.0 (5.00)
3 190.5 (7.50) 254.0 (10.
...