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Title: Delamination mechanism maps for a strong elastic coating on an elastic-plastic substrate subjected to contact loading

Abstract

Hard wear resistant coatings that are subjected to contact loading sometimes fail because the coating delaminates from the substrate. In this report, systematic finite element computations are used to model coating delamination under contact loading. The coating and substrate are idealized as elastic and elastic-plastic solids, respectively. The interface between coating and substrate is represented using a cohesive zone law, which can be characterized by its strength and fracture toughness. The system is loaded by an axisymmetric, frictionless spherical indenter. We observe two failure modes: shear cracks may nucleate just outside the contact area if the indentation depth or load exceeds a critical value; in addition, tensile cracks may nucleate at the center of the contact when the indenter is subsequently removed from the surface. Delamination mechanism maps are constructed which show the critical indentation depth and force required to initiate both shear and tensile cracks, as functions of relevant material properties. Numerical results have also been compared to analytical analysis using beam bending and membrane stretching theories.

Authors:
 [1];  [2];  [1];  [3];  [3]
  1. Brown University
  2. ORNL
  3. General Motors Corporation-R&D
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Computational Sciences
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931646
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: International Journal of Solids and Structures; Journal Volume: 44; Journal Issue: 11-12
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; PROTECTIVE COATINGS; FRACTURE PROPERTIES; CRACKS; FAILURE MODE ANALYSIS; WEAR RESISTANCE; FINITE ELEMENT METHOD; ELASTICITY; PLASTICITY; SUBSTRATES

Citation Formats

Xia, Shuman, Gao, Yanfei, Bower, Allan F., Lev, Leo C., and Cheng, Yang-Tse. Delamination mechanism maps for a strong elastic coating on an elastic-plastic substrate subjected to contact loading. United States: N. p., 2007. Web. doi:10.1016/j.ijsolstr.2006.10.009.
Xia, Shuman, Gao, Yanfei, Bower, Allan F., Lev, Leo C., & Cheng, Yang-Tse. Delamination mechanism maps for a strong elastic coating on an elastic-plastic substrate subjected to contact loading. United States. doi:10.1016/j.ijsolstr.2006.10.009.
Xia, Shuman, Gao, Yanfei, Bower, Allan F., Lev, Leo C., and Cheng, Yang-Tse. Mon . "Delamination mechanism maps for a strong elastic coating on an elastic-plastic substrate subjected to contact loading". United States. doi:10.1016/j.ijsolstr.2006.10.009.
@article{osti_931646,
title = {Delamination mechanism maps for a strong elastic coating on an elastic-plastic substrate subjected to contact loading},
author = {Xia, Shuman and Gao, Yanfei and Bower, Allan F. and Lev, Leo C. and Cheng, Yang-Tse},
abstractNote = {Hard wear resistant coatings that are subjected to contact loading sometimes fail because the coating delaminates from the substrate. In this report, systematic finite element computations are used to model coating delamination under contact loading. The coating and substrate are idealized as elastic and elastic-plastic solids, respectively. The interface between coating and substrate is represented using a cohesive zone law, which can be characterized by its strength and fracture toughness. The system is loaded by an axisymmetric, frictionless spherical indenter. We observe two failure modes: shear cracks may nucleate just outside the contact area if the indentation depth or load exceeds a critical value; in addition, tensile cracks may nucleate at the center of the contact when the indenter is subsequently removed from the surface. Delamination mechanism maps are constructed which show the critical indentation depth and force required to initiate both shear and tensile cracks, as functions of relevant material properties. Numerical results have also been compared to analytical analysis using beam bending and membrane stretching theories.},
doi = {10.1016/j.ijsolstr.2006.10.009},
journal = {International Journal of Solids and Structures},
number = 11-12,
volume = 44,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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