Sonic Investigations on Internal Damping in Solids

Sound attenuation and anharmonic damping in solids with correlated disorder

W. Schirmacher1,2, C. Tomaras3, B. Schmid2, G. Baldi4, G. Viliani5 , G. Ruocco6,7, T. Scopigno6,7 1 Physik-Department E13, Technische Universität München, James-Franck-Strasse 1, D–85747 Garching, Germany 2 Fachbereich Physik, Universität Mainz, Germany 3 Arnold Sommerfeld Center for Theoretical Physics, Ludwig-Maximilians-Universität München, Theresienstr. 37, D–80333 München, Germany 4 ESRF G...

On the Problem of Semiinfinite Beam Oscillation with Internal Damping*

We study the Cauchy problem for the equation of the form (*) ü(t) + (αA+ B)u̇(t) + (A+G)u(t) = 0 where A, B, and G are operators in a Hilbert space H with A selfadjoint, σ(A) = [0,∞), B > 0 bounded, and G symmetric and Asubordinate in a certain sense. Spectral properties of the corresponding operator pencil L(λ) := λI +λ(αA+B) + A+G are studied, and existence and uniqueness of generalized and cl...

Investigations of Process Damping Forces in Metal Cutting

Using finite element software developed for metal cutting by Third Wave Systems we investigate the forces involved in chatter, a self-sustained oscillation of the cutting tool. The phenomena is decomposed into a vibrating tool cutting a flat surface work piece, and motionless tool cutting a work piece with a wavy surface. While cutting the wavy surface, the shearplane was seen to oscillate in a...

A modular bearing with internal piezoshunt damping

When a piezoelectric transducer is incorporated in a mechanical structure, it is possible to damp the structural vibrations of the base structure by passive energy dissipation in the electrical domain [1]. Due to the strong electromechanical coupling in piezoelectric elements, the mechanical energy can be efficiently converted to electrical energy. By shunting the piezoelectric element to a pas...

Young's Modulus and Internal Damping in a Vibrating Rod