Nontraditional Applications of Damping Measurements

Abstract

Damping measurements have been traditionally of interest to those concerned with noise and vibration control or microstructural relaxations of metallic materials. This paper discusses some recent nontraditional applications of damping measurements that are not related to either of those topics. These results have important implications for nondestructive evaluation, quality control and alternative approaches to characterization of nonmetallic and composite structures and materials. Recent examples of nondestructive evaluation applications of damping measurements include studies of damage, defects, and degradation in composite materials and structures and the effects of environmental conditions on material behavior. Specific examples include the use of damping measurements in studies of cracks, interfacial debonds, delaminations, and environmentally-induced degradation in composite materials. It has also been shown that the time domain creep and relaxation properties of viscoelastic materials can be obtained from frequency domain measurements of damping and stiffness, and the feasibility of developing a rapid screening test for creep susceptibility based on such measurements is discussed.