ASTM E756-05 Measuring Vibration-Damping Properties of Materials

Scope:

The ASTM E756-05 test method involves loss factor and modulus of damping materials that are useful for determining how to control vibration in structures and the sound emitted by those structures, particularly during resonance. 

Procedure:

Over a wide range of modulus values, different test specimens were employed to explore extensional and shear damping properties of materials. Forming a single, uniform test beam from the damping material itself is used to evaluate self-supporting damping materials. Non-self-supporting damping materials are evaluated in a two-step process requiring two identical base beams. 

Specimen size:

The specimen should be conditioned at ±0.5mm in length and ±0.05mm in thickness.

Calculation:

Young’s modulus and loss factor can be calculated by using the following formula:

E = (12ρl⁴ f²n)/ (H² C²n)
And η = (f_n)/ (f_n)
E = young’s modulus
C = coefficient
Fn = resonance frequency for mode n
L = length
η = loss factor
ρ = density