Anisotropic elastic properties of thermal spray coatings determined via resonant ultrasound spectroscopy

Elastic moduli and elastic anisotropy of cold sprayed metallic coatings

“…the amplitude dependence of the elastic moduli [32]), the map in Fig. 7 comprises only the results obtained by ultrasonic methods, in particular by pulse-echo [25], RUS [19,26] or by their combination [23]; therefore, all these results refer to very small straining amplitudes and high straining rates typical for ultrasound. The CS materials obviously possess a unique combination of high E OOP /E bulk ratio and very weak anisotropy.…”

“…Among the sprayed metallic prepared by water-stabilized plasma (WSP) spraying. In all reported cases, the difference between the in-plane and out-of plane properties of the coatings were significant, with the values of the ratio α = E OOP /E IP between the out-of-plane Young's modulus (E OOP ) and the in-plane Young's modulus (E IP ) ranging from 0.36 (for APS [19]) to 0.87 (for WSP [23]). Here we apply this method to determine the elastic constants and the strength of anisotropy for pure copper, aluminum, titanium and nickel coatings prepared by CS.…”

“…All samples were oriented so that longest and the shortest edge of the sample were always perpendicular to the spraying direction and aligned with the directions of motion of the nozzle during spraying. However, it was assumed (as usual for the sprayed materials [19,23,25,26]) that all samples exhibit transversal isotropy, i.e. that all directions perpendicular to the spraying direction are equivalent, and the elasticity of the material can be fully described by five independent elastic coefficients.…”

Anisotropic elastic properties of chiral sculptured thin films at micro-scale evaluated by resonance frequency spectra

“…The development of dynamic techniques to determine the anisotropic elastic properties enables an understanding of the role of microstructural features and linkages to processing conditions (Tan et al, 2010). Some dynamic studies use fixed-free or freeefree resonance bar techniques, and composite oscillator techniques (Gregori et al, 2007).…”

Application of resonant ultrasound spectroscopy to determine elastic constants of plasma-sprayed coatings with high internal friction

“…Most recently, Tan et al [24] have applied resonant ultrasound spectroscopy (RUS, [25,26]) to determine elastic constants of freestanding coatings prepared by atmospheric plasma spraying (APS) and high-velocity oxygen-fuel (HVOF)process. RUS is an advanced ultrasonic method based on determination of the elastic moduli from resonant spectra of free elastic vibrations of a small sample of the examined material.…”