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ASTM D 638 and ISO 527-1 are
technical equivalents. This test method is designed
to determine the tensile properties of plastic materials. And can be used for
testing materials of any thickness up to 14 mm [0.55 in.].
However, it is preferable to use ASTM Test Methods D 882
for specimens of thin sheeting including films less than 1.0mm [0.04 in.] All
materials of a thickness of greater than 14 mm.[0.55in.] must be reduced by
machining before this method can be applied.
The
Tensile Properties of
reinforced and unreinforced plastics may be determined using standard
dumbbell-shaped test specimens tested under defined conditions of pretreatment,
temperature, humidity, and testing machine speed. These properties include: True
stress and strain, Engineering Stress and Strain, the Elastic Modulus, the
Ultimate Tensile Strength, the Fracture Stress, the Modulus of Toughness, and
the Modulus of Resilience,
Poisson’s ratio at room
temperature also may be determined using the ASTM D 638 test method.
Poisson's ratio is a measure of transverse strain versus axial strain when
unaxial stress is applied.
Poisson's ratio is important when
an engineer needs to design for all dimensional
changes due to applied forces. Poisson's ratio is also employed when applying
the generalized theory of elasticity to structural analysis.
To obtain complete
specifications go
to
ASTM International.
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