Measurement of the viscoelastic properties of materials with a very large loss factor by a two-parameter method

An analysis is made of the feasibility of measuring the viscoelastic properties of materials having a loss factor greater than 1. A conclusion is made as to the suitability of a two-parameter method for measuring the properties of such materials at phase angles θ>100°. Diagrams of the strains and the phase change through the thickness of the specimen are presented, these diagrams illustrating the sound-absorbing and soundinsulating capabilities of such materials. To facilitate practical use of the proposed method, calculated values of coefficients for determining the elastic modulus and loss factor are reported along with parameter measurements made at θ=130°.