Damping Optimization of Hard-Coating Thin Plate by the Modified Modal Strain Energy Method

Abstract

Due to the medium and small damping characteristics of the hard coating compared with viscoelastic materials, the classical modal strain energy (CMSE) method cannot be applied to the prediction of damping characteristics of hard-coating composite structure directly. In this study, the CMSE method was modified in order to be suitable for this calculation, and then the damping optimization of the hard-coating thin plate was carried out. First, the solution formula of modified modal strain energy (MMSE) method was derived and the relevant calculation procedure was proposed. Then, based on the principle that depositing the hard coating on the locations where modal strain energy is higher, the damping optimization method and procedure were presented. Next, a cantilever thin plate coated with Mg-Al hard coating was taken as an example to demonstrate the solution of the modal damping parameters for the composite plate. Finally, the optimization of coating location was studied according to the proposed method for the cantilever thin plate, and the effect of the coating area on the damping characteristics of hard-coating plate was also discussed.

Application of the hard-coating damper on the mistuned blisk for passive vibration reduction

“…Therefore, modal loss factors of the HCM blisk which can represent the damping capacities typically were significant to be evaluated here. To estimate the damping capacities of the vibrating structures well, the energy-based method has been commonly used by some researchers, such as Sun and Liu 27 and Curà et al. 52 By using the modal strain energy (MSE) method in this work, modal loss factors of the HCM blisk can be given as follows where ηb and ηc represent the material loss factor of the blisk and the hard-coating damper, respectively; MSEb,j and MSEc,j refer to the MSE of the blisk and the hard-coating damper, respectively.…”

“…[21][22][23] In recent years, the significant damping capacities of hard coating produced by internal particles friction have been found by some scholars. 24 Subsequently, the vibration reduction technology by the hard-coating dampers was widely applied to reduce the resonant stress of vibrating structures, such as the titanium plates, [25][26][27] cantilever beams, 28 cylindrical thin shells, 29,30 individual blades 31,32 and highly simplified blisk, 33,34 for its nicer stability than viscoelastic materials under high temperature and pressure. 35 Another great advantage of the hard-coating dampers was that the resonant peaks of vibrating structures can be suppressed remarkably without alerting structural mass and stiffness significantly because of its thin thickness.…”

Passive Vibration Reduction Analysis of the Mistuned Blisk Deposited Hard Coating Using Modified Reduced-Order Model

“…In recent years, the significant mechanical damping capacities of hard coating generated by the friction energy dissipation of internal particles of coating materials [22] have been found by a number of researchers. Subsequently, hard coating was used widely as the vibration dampers to reduce the resonant stress of vibrating structures for its nicer stability and high damping capacities in high temperature [23], such as the titanium plates [24][25][26][27], the cantilever beams [28,29], the cylindrical thin shells [30][31][32] and the individual blades [33][34][35], etc. Moreover, another great advantage of hard coating was that the resonant peaks of the forced response of vibrating structures can be suppressed remarkably without influencing the structural mass and stiffness significantly because of its thin thickness.…”