The Characteristics of Temperature/Frequency-Dependent Damping and Quasi-Non-Stationary Random Dynamic Method

The damping characteristic of a specific type of high-strength alloys was researched by using a dynamic mechanical analyzer (DMA) and via the application of viscoelastic damping theory. The characteristics of temperature/frequency-dependent damping and coupling factor are provided from the perspective of dynamic applications. Consider the evolution of damping characteristics. The evolution can be expressed as a time-dependent term and a non-time-dependent term. This time-dependent-term variable damping nonlinear stochastic dynamic analysis method was proposed according to the random vibration of magnesium alloy structures. The quasi-non-stationary random analysis method of stationary problems was established based on the solution characteristics of the pseudo-excitation method. In contrast, from the numerical analysis results and experiments conducted on magnesium alloy structures, it is demonstrated that the analysis results of constant damping systems have obvious inconsistencies with the experimental results. The calculation results based on variable damping systems were more consistent with experimental results. It is suggested that variable damping theory should be used in the dynamic structural analysis of the magnesium alloy material under consideration in fields and applications with higher accuracy requirements.