Polyhedron – Mechanical Testing
Polyhedron Laboratories performs mechanical testing
according to ASTM standards, such as Abrasion Resistance with the
Taber Abraser (ASTM D1044, D4060), Coefficient of Friction of
Plastic Film (ASTM D1894), Compressive Testing (ASTM D695), Dynamic
Mechanical Analysis, from –100 to 200 Degrees Centigrade (ASTM
D5026), Flexural Strength (ASTM D790), Hardness (Durometer) (ASTM
D2240), Hardness (Rockwell) (ASTM D785), Izod Impact (ASTM D256A),
Shear Strength (ASTM D732), Tear Resistance (ASTM D1004), Tensile
Properties of Plastics/Strength and Elongation (ASTM D638), Tensile
Modulus (ASTM D638), Compression Properties of Rigid Cellular
Plastics (ASTM D1621) and Tensile Properties of Rigid Cellular
Plastics (ASTM D1623). Polyhedron also offers
tensile testing from –100 to 200 Degrees Centigrade. All ASTM
standard descriptions below are paraphrased from the ASTM website (www.astem.org).
Due to copyright restrictions, Polyhedron Laboratories cannot
make available copies of standards. Standards can be found and are
available at www.astm.org.
Abrasion Resistance with the Taber
Abraser:
ASTM D1044-05 - Standard Test Method
for Resistance of Transparent Plastics to Surface Abrasion - This
test procedure describes a method for estimating the resistance of
transparent plastics to one kind of surface abrasion by measurement
of its optical properties. Abrasive damage is judged by the
percentage of transmitted light that, in passing through the abraded
track, deviates from the incident beam by forward scattering. For
the purpose of this test procedure, only light flux deviating more
than 0.044 rad (2.5°) on average is considered in this
assessment of abrasive damage. Abrasive damage is visually judged
and numerically quantified by the difference in haze percentage
between an abraded and unabraded specimen. This procedure has been
successfully used with plastic films and sheeting.
ASTM D4060-01 - Standard Test
Method for Abrasion Resistance of Organic Coatings by the Taber
Abraser - This test procedure deals with the determination of the
resistance of organic coatings to abrasion created by the Taber
Abraser on coatings applied to a plane, rigid surface, such as a
metal panel. This test method is most successful when testing in
only one laboratory where numerical abrasion resistance values are
to be used. Inter-laboratory results are notably improved when
rankings of coatings are used in place of numerical values.
Coefficient of Friction of Plastic Film:
ASTM D1894-01 - Standard Test Method for Static and Kinetic
Coefficients of Friction of Plastic Film and Sheeting - This test
procedure outlines the determination of the coefficients of sliding
and starting friction of plastic sheeting and film when sliding over
it or other substances at specific test conditions. The test method
permits the use of a moving sled with a stationary plane or a
stationary sled with a moving plane. Both test methods yield the
same coefficients of friction values for a given specimen.
Compression Testing
ASTM D695-02a - Standard Test Method for Compressive Properties of
Rigid Plastics - This test procedure deals with the determination of
the mechanical properties of reinforced and unreinforced rigid
plastics, including high-modulus composites, when loaded in
compression at relatively low uniform rates of loading or straining.
Test samples of standard shapes are employed.
Dynamic Mechanical Analysis (-100 to 200
Degrees Centigrade)
ASTM D5026-01- Standard Test Method for Plastics: Dynamic
Mechanical Properties: In Tension - This test procedure outlines the
use of dynamic mechanical instrumentation for reporting and
gathering the viscoelastic properties of thermosetting and
thermoplastic resins and composite systems in the form of
rectangular samples molded directly or cut from molded shapes,
plates or sheets – only small samples are needed. This test
procedure provides a means for determining the modulus as a function
of temperature of a wide variety of plastics materials using
nonresonant forced-vibration techniques. Plots of the loss
(viscous); elastic (storage); and complex moduli and tan delta as a
function of temperature, time, or frequency indicate considerable
transitions in the thermomechanical performance of the polymeric
material system. This is the best method for determining the glass
transition temperature. This test procedure is valid for a wide
range of frequencies from 0.01 to 100 Hz.
Flexural Strength
ASTM D790-03 - Standard Test Methods for Flexural Properties of
Unreinforced and Reinforced Plastics and Electrical Insulating
Materials - These test procedures deal with the determination of
flexural properties of reinforced and unreinforced plastics,
including electrical insulating materials and high-modulus
composites in the form of rectangular bars molded directly or cut
from molded shapes, plates or sheets. These test routines are
generally applicable to both semi-rigid and rigid materials. These
test procedures utilize a three-point loading system that is applied
to a simply supported beam. Test Method A is designed principally
for materials that break at comparatively small deflections; Test
Method B is designed particularly for those materials that undergo
large deflections during testing.
Hardness (Durometer)
ASTM D2240-05 - Standard Test Method for Rubber
Property—Durometer Hardness - This test procedure outlines
twelve types of rubber hardness measurement devices known as
durometers: Types A, B, C, and D. The procedure for determining
indentation hardness of substances classified as vulcanized
(thermoset) rubber, thermoplastic elastomers, cellular materials,
elastomeric materials, gel-like materials, and some plastics are
also described.
Hardness (Rockwell)
ASTM D785-03 - Standard Test Method for Rockwell Hardness of
Plastics and Electrical Insulating Materials - This test procedure
outlines two methods for testing the indention hardness of plastics
and related plastic electrical insulating materials using a Rockwell
hardness tester.
Izod Impact
ASTM D256-06 - Standard Test Methods for Determining the Izod
Pendulum Impact Resistance of Plastics - These test procedures cover
the determination of the resistance of plastics to
"standardized" pendulum-type hammers, mounted in
"standardized" machines, in breaking standard samples with
one pendulum swing. The standard tests for these test routines
require samples made with a milled notch. In Test Procedures A, C,
and D, the notch produces a stress concentration that increases the
probability of a brittle, rather than a ductile, fracture. In Test
Procedure E, the impact resistance is obtained by reversing the
notched specimen 180 degrees in the clamping vise. The results of
all test procedures are reported in terms of energy absorbed per
unit of specimen width or per unit of cross-sectional area under the
notch.
Shear Strength
ASTM D732-02- Standard Test Method for Shear Strength of
Plastics by Punch Tool - This test procedure outlines the punch-type
of shear test and is intended for use in determining the shear
strength of test specimens of organic plastics in the form of molded
discs and sheets in thicknesses from 0.127 to 12.7 millimeters
(0.050 to 0.500 inches).
Tear Resistance
ASTM D1004-03 - Standard Test Method for Initial Tear
Resistance of Plastic Film and Sheeting - This test procedure deals
with the determination of the tear resistance of flexible sheeting
and plastic film at very low rates of loading, 51 millimeters (2
inches)/min. and is designed to measure the force to initiate
tearing. The sample geometry of this test routine produces a stress
concentration in a small area of the sample. The maximum stress,
typically found at the onset of tearing, is recorded as the tear
resistance in newtons (or pounds-force).
Tensile Properties of Plastics/Strength
and Elongation/Tensile Modulus
ASTM D638-03- Standard Test Method for Tensile Properties of
Plastics - This test procedure deals with the determination of the
tensile properties of reinforced and unreinforced plastics in the
form of standard dumbbell-shaped test samples when tested under
defined conditions of humidity, temperature, pretreatment, and
testing machine speed. This test procedure can also be used for
testing materials of any thickness up to 0.25 inches. Materials with
a thickness greater than 0.25 inches must be reduced by machining.
Compression Properties of Rigid Cellular
Plastics
ASTM D1621-04a -Standard Test Method for Compressive
Properties of Rigid Cellular Plastics - This test procedure outlines
a method for determining the compressive properties of rigid
cellular materials, particularly expanded plastics.
Tensile Properties of Rigid Cellular
Plastics
ASTM D1623-03- Standard Test Method for Tensile and Tensile
Adhesion Properties of Rigid Cellular Plastics - This test procedure
deals with the determination of the tensile and tensile adhesion
properties of rigid cellular materials in the form of test samples
of standard shape under defined conditions of testing machine speed,
humidity and temperature. Tensile properties shall be measured using
three types of samples – Type A is the preferred sample in
those cases where enough material exists to form the required
sample; Type B is the preferred sample when only smaller samples are
available, as in sandwich panels and the like; Type C is the
preferred sample for the determination of tensile adhesive
properties of a cellular plastic to a substrate as found in a
sandwich panel or the bonding strength of a cellular plastic to a
single substrate.
Creep Testing
ASTM D2990-01- Standard Test Methods for Tensile,
Compressive, and Flexural Creep and Creep-Rupture of Plastics -
These test procedures outline the determination of tensile and
compressive creep and creep-rupture of plastics under specified
environmental conditions. For measurements of creep-rupture, tension
is the preferred stress mode because for some ductile plastics
rupture doesn’t occur in flexure or compression.
|