Design Guide - Solvay Plastics

Figure 37: Notched Charpy Impact Strength of
30%-33% GR Resins
Table 17: Penetration Impact (ASTM D3763) of
Impact Modified PPA
Charpy Impact Strength, kJ/m 2
14
12
10
8
6
4
2
0
A-1133 HS PA 6,6 PPS PEI
DAM
50% RH
2.0
1.5
1.0
0.5
0.0
Charpy Impact Strength, ft-lb/in 2
Max Load Total Energy
Grade Condition N lb J ft-lb
AT-1001 L DAM 4,900 1,100 54 40
AT-1002 HS DAM 4,400 1,000 54 40
AT-1002 HS 50% RH 4,000 900 47 35
AT-5001 DAM 4,400 1,000 54 40
AT-5001 50% RH 4,000 900 50 37
ET-1000 HS DAM 4,670 1,050 54 40
Falling Weight Impact Properties
ASTM D3763, High-Speed Puncture Properties of
Plastics Using Load and Displacement Sensors, was
used to measure the practical toughness of Amodel
polyphthalamide resins.
In this test, an injection molded specimen is clamped
down over a 76 mm (3 in.) diameter hole and a weighted
plunger is dropped from a predetermined height to give
it a predetermined impact velocity. The plunger assembly
consists of a 12.7 mm (0.500 in.) diameter steel rod with
a hemispherical end. The plunger assembly is attached
to a load cell which measures the energy needed to
cause a sample to fail.
Specimens can fail in either a brittle or a ductile mode.
In a ductile failure mode, the specimen is permanently
deformed to the shape of the plunger, but remains in
one piece after the penetration by the plunger. In a brittle
failure mode, the specimen does not have sufficient
ductility to be deformed without failure, and therefore
breaks into two or more pieces when impacted by
the plunger.
This method is preferred to ASTM D3029, because
although the impact values obtained are similar in
nature to the "stair step" falling weight impact test,
the instrumented test results are obtained via a
computerized data reduction technique and fewer
samples are required.
ET-1001 L DAM 5,600 1,260 64 47
Poisson’s Ratio
Poisson’s ratio is a measure of the strain characteristics
imposed on a material transverse to the applied load.
Poisson’s ratio is the ratio of lateral strain to longitudinal
strain within the proportional limit. To illustrate, consider
a cylindrical bar subjected to tensile stress, the length (L)
increases and simultaneously its diameter (D) decreases.
In this case, Poisson’s ratio (υ) would be calculated by:
-ΔD
D
υ =
ΔL
L
Most plastic materials have a Poisson’s ratio between
0.3 and 0.5.
Table 18 gives the Poisson’s ratios for various Amodel
formulations at 23°C (73°F), "dry, as molded".
30 Amodel ® PPA Design Guide
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