Abstract

Physical vapor deposited (PVD) coatings have low effective stiffness Eeff (as compared to the bulk material) in directions parallel to the substrate. It increases with an increasing residual compressive stress. A simple micromechanical model, based on the contact problem, is constructed that explains the observed behavior. Quantitative characterization of microstructure relevant for Eeff is developed.

Issue Section:
Technical Papers
Keywords:
PVD Coating, Microstructure, Elasticity, vapour deposited coatings, elastic constants, elasticity, internal stresses, micromechanics, mechanical contact, crystal microstructure
Topics:
Coatings, Elasticity, Stiffness, Stress, Compressive stress
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Copyright © 2002
 by ASME
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