ISO 18437-4:2008
Mechanical vibration and shock - Characterization of the dynamic mechanical properties of visco-elastic materials - Part 4 : dynamic stiffness method
ISO 18437-4:2008 specifies a direct method for measuring the complex dynamic moduli of elasticity (the Young, shear and bulk moduli, and their respective loss factors corresponding to the tensile, shear and all compressive strains) for polymeric (rubbery and viscous polymers, as well as rigid plastics) materials over a wide frequency and temperature range. Measurements are performed by the dynamic stiffness method, which uses electric signals from sensors attached to a test piece. These signals are proportional to the dynamic forces acting on the test piece and the strains in the test piece due to the effect of these forces.The measurement frequency range is determined by the size of test piece, the accuracy required on the dynamic modulus measurements, the relationship between the stiffness of the oscillation generator and the stiffness of the test piece, and by the resonance characteristics of the test fixture used.The method presented in ISO 18437-4:2008 allows measurement under any static pre-load allowed for the test piece (including the test piece having the non-linear characteristics under different static loads), but under small dynamic (acoustic) strains, i.e. in limits where the linear properties of the test piece are not distorted. Depending on the pre-load conditions, the relation between the moduli is unique.
ISO 18437-4:2008 specifies a direct method for measuring the complex dynamic moduli of elasticity (the Young, shear and bulk moduli, and their respective loss factors corresponding to the tensile, shear and all compressive strains) for polymeric (rubbery and viscous polymers, as well as rigid plastics) materials over a wide frequency and temperature range. Measurements are performed by the dynamic stiffness method, which uses electric signals from sensors attached to a test piece. These signals are proportional to the dynamic forces acting on the test piece and the strains in the test piece due to the effect of these forces.
The measurement frequency range is determined by the size of test piece, the accuracy required on the dynamic modulus measurements, the relationship between the stiffness of the oscillation generator and the stiffness of the test piece, and by the resonance characteristics of the test fixture used.
The method presented in ISO 18437-4:2008 allows measurement under any static pre-load allowed for the test piece (including the test piece having the non-linear characteristics under different static loads), but under small dynamic (acoustic) strains, i.e. in limits where the linear properties of the test piece are not distorted. Depending on the pre-load conditions, the relation between the moduli is unique.
The Requirements department helps you quickly locate within the normative text:
- mandatory clauses to satisfy,
- non-essential but useful clauses to know, such as permissions and recommendations.
The identification of these types of clauses is based on the document “ISO / IEC Directives, Part 2 - Principles and rules of structure and drafting of ISO documents ”as well as on a constantly enriched list of verbal forms.
With Requirements, quickly access the main part of the normative text!

COBAZ is the simple and effective solution to meet the normative needs related to your activity, in France and abroad.
Available by subscription, CObaz is THE modular solution to compose according to your needs today and tomorrow. Quickly discover CObaz!
Request your free, no-obligation live demo
I discover COBAZ