How do you find the loss factor in hysteretic damping?

Answer 1

Loss factor is best obtained by dynamically loading (extensional, torsional etc.) a specimen of the material and plotting the hysteresis curve in stress-vs strain plane. If the total area under the hysteresis loop is D, the loss factor is computed from the following formula Loss factor=D/(2*pi*max stress* max strain) For lightly damped materials, loss factor is just twice the daming factor 'zeta' which obtained either by log-decrement method or half-power bandwidth method. Loss factor is best obtained by dynamically loading (extensional, torsional etc.) a specimen of the material and plotting the hysteresis curve in stress-vs strain plane. If the total area under the hysteresis loop is D, the loss factor is computed from the following formula Loss factor=D/(2*pi*max stress* max strain) For lightly damped materials, loss factor is just twice the daming factor 'zeta' which obtained either by log-decrement method or half-power bandwidth method.