• Structural Engineering and Mechanics
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• v.6 no.3
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• pp.291-304
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• 1998

This paper deals with the non-axisymmetric dynamic response of an imperfectly bonded buried orthotropic pipeline subjected to longitudinal wave (P-wave) excitation. An infinite cylindrical shell model, including the rotary inertia and shear deformation effects, has been used for the pipeline. For some cases comparison of axisymmetric and non-axisymmetric responses have also been furnished.

• Journal of the Korean Ceramic Society
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• v.36 no.4
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• pp.444-450
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• 1999

Hydroxyapatite(HA) was spray-coated to alloy substrate(Ti-6Al-4V) using plasma-spray process for bioceramic application The coating morphology composition and crystallinity were influenced by following process parameters ; stand-off distance spray power level and auxiliary gas pressure. These parameters have been systematically varied in the present study to evaluate their relative influence on the coating qual-ity and to seek an optimum spraying condition. Amorphicity and decomposition of HA increased with stand-off distance and the imperfect coating layer was obtained at the short stant-off distance (55mm). The cry-stallinity of HA coating decreased with spray power level and auxiliary gas pressure but the bond strength between the HA coated layer and Ti alloy substrate increased with the spray power level.