Meaning
Global standard guidelines specify the test conditions and sample geometries for determining the tensile properties of moulding and extrusion plastics. Applying ISO 527-2 yields the tensile modulus and tensile strength required to calculate the mechanical load-bearing capacity of a polymer part. This procedure ensures that material datasheets can be compared across global suppliers.
Mechanical Testing
Tensile specimens are gripped in a universal testing machine and pulled at a constant rate until failure occurs. Standard measurements under ISO 527-2 rely on precise extensometers to track the deformation of the specimen within its narrow parallel region. Stress and strain are calculated directly.
Yield Stress
Ductile polymers display a distinct yield point before plastic deformation occurs. Evaluation under ISO 527-2 identifies the yield stress, which represents the maximum load a part can withstand before permanent deformation ruins its assembly.
Sourcing Security
Sourcing alternative resin grades requires evaluating whether the tensile strength matches the original specification to avoid part failures. While virgin resins exhibit high consistency in tensile modulus, regrind content can lower the yield strength and ultimate elongation due to molecular chain degradation. Regular testing of production samples helps the moulder confirm that the structural integrity of the part remains within specified limits.
