Wrinkling of a thin film-substrate with a shear-lag model at the interface

2021 ◽  
pp. 138765
Author(s):  
Masoud Noroozi
Keyword(s):  
Thin Film ◽  
Shear Lag ◽  
Shear Lag Model ◽  
Lag Model ◽  
Film Substrate

scholarly journals Constraint Effects on Thin Film Channel Cracking Behavior

2005 ◽  
Vol 20 (9) ◽  
pp. 2266-2273 ◽  
Author(s):  
Ting Y. Tsui ◽  
Andrew J. McKerrow ◽  
Joost J. Vlassak
Keyword(s):  
Thin Film ◽  
Residual Stress ◽  
Buffer Layer ◽  
Layer Thickness ◽  
Silicon Substrate ◽  
Shear Lag ◽  
Shear Lag Model ◽  
Lag Model ◽  
Buffer Layer Thickness ◽  
Cds Film

One of the most common forms of cohesive failure observed in brittle thin film subjected to a tensile residual stress is channel cracking, a fracture mode in which through-film cracks propagate in the film. The crack growth rate depends on intrinsic film properties, residual stress, the presence of reactive species in the environments, and the precise film stack. In this paper, we investigate the effect of various buffer layers sandwiched between a brittle carbon-doped-silicate (CDS) film and a silicon substrate on channel cracking of the CDS film. The results show that channel cracking is enhanced if the buffer layer is more compliant than the silicon substrate. Crack velocity increases with increasing buffer layer thickness and decreasing buffer layer stiffness. This is caused by a reduction of the constraint imposed by the substrate on the film and a commensurate increase in energy release rate. The degree of constraint is characterized experimentally as a function of buffer layer thickness and stiffness, and compared to the results of a simple shear lag model that was proposed previously. The results show that the shear lag model does not accurately predict the effect of the buffer layer.

A Theory for Multi Damage Evaluation of TiN Thin Film

2000 ◽  
Vol 653 ◽  
Author(s):  
Kazunori Misawa ◽  
Tomonaga Okabe ◽  
Masaaki Yanaka ◽  
Masao Shimizu ◽  
Nobuo Takeda
Keyword(s):  
Thin Film ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Titanium Alloy ◽  
Tensile Load ◽  
Damage Evaluation ◽  
Shear Lag ◽  
New Approach ◽  
Shear Lag Model ◽  
Lag Model

AbstractThe present paper experimentally studies the cracking phenomena of a TiN thin film on a titanium alloy, and presents a new approach to predict the number of cracks under tensile load. An elastoplastic shear-lag model is developed to obtain the stress distribution caused by the film cracks, which is found to agree well with that calculated with FEM. The number of thin film cracks is predicted using a Monte Carlo simulation using the present approach, and favourably compared with the experimental results.

scholarly journals Stress Transfer from Axially Loaded Fiber to Matrix in a Microcomposite

1994 ◽  
Vol 365 ◽  
Author(s):  
Chun-Hway Hsueh
Keyword(s):  
Analytical Solutions ◽  
Volume Fraction ◽  
Axial Stress ◽  
Stress Transfer ◽  
Radial Dependence ◽  
Shear Lag ◽  
Shear Lag Model ◽  
The Matrix ◽  
Lag Model ◽  
Loaded Fiber

ABSTRACTThe shear lag model has been used extensively to analyze the stress transfer in a singe fiberreinforced composite (i.e., a microcomposite). To achieve analytical solutions, various simplifications have been adopted in the stress analysis. Questions regarding the adequacy of those simplifications are discussed in the present study for the following two cases: bonded interfaces and frictional interfaces. Specifically, simplifications regarding (1) Poisson's effect, and (2) the radial dependences of axial stresses in the fiber and the matrix are addressed. For bonded interfaces, the former can be ignored, and the latter can generally be ignored. However, when the volume fraction of the fiber is high, the radial dependence of the axial stress in the fiber should be considered. For frictional interfaces, the latter can be ignored, but the former should be considered; however, it can be considered in an average sense to simplify the analysis. Comparisons among results obtained from analyses with various simplifications are made.

scholarly journals On the Stress Transfer of Nanoscale Interlayer with Surface Effects

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Quan Yuan ◽  
Mengjun Wu
Keyword(s):  
Surface Effect ◽  
Surface Elasticity ◽  
Stress Transfer ◽  
Interfacial Stress ◽  
Interlayer Thickness ◽  
Shear Lag ◽  
Multilayered Structures ◽  
Residual Surface Stress ◽  
Shear Lag Model ◽  
Lag Model

An improved shear-lag model is proposed to investigate the mechanism through which the surface effect influences the stress transfer of multilayered structures. The surface effect of the interlayer is characterized in terms of interfacial stress and surface elasticity by using Gurtin–Murdoch elasticity theory. Our calculation result shows that the surface effect influences the efficiency of stress transfer. The surface effect is enhanced with decreasing interlayer thickness and elastic modulus. Nonuniform and large residual surface stress distribution amplifies the influence of the surface effect on stress concentration.

Investigation of Damage in Unidirectional Ceramic Matrix Composites Using a Cohesive-Shear-Lag Model

2001 ◽  
Author(s):  
B. Yang ◽  
S. Mall
Keyword(s):  
Ceramic Matrix Composites ◽  
Ceramic Matrix ◽  
Interfacial Debonding ◽  
Matrix Composites ◽  
Fiber Reinforced ◽  
Shear Lag ◽  
Stress Strain ◽  
Unidirectional Fiber ◽  
Shear Lag Model ◽  
Lag Model

Abstract The present study develops a cohesive-shear-lag model to analyze the cycling stress-strain behavior of unidirectional fiber-reinforced ceramic matrix composites. The model, as a modification to a classical shear-lag model, takes into account matrix cracking, partial interfacial debonding, and partial breakage of fibers. The statistical nature of partial breakage of fibers is modeled by using a cohesive force law. The validity of the model is demonstrated by investigating stress-strain hysteresis loops of a unidirectional fiber-reinforced ceramic-glass matrix composite, SiC/1723. This example demonstrates the capability of the proposed model to characterize damage and deformation mechanisms of ceramic matrix composites under tension-tension cycling loading. The dominant progressive damage mechanism with cycling in this case is shown to be accumulation of fibers breakage, accompanied by increase in interfacial debonding and smoothening of frictional debonded interface.

Dynamic Shear-Lag Model for Stress Transfer in Piezoelectric Transducer Bonded to Plate

AIAA Journal ◽  
2019 ◽  
Vol 57 (5) ◽  
pp. 2123-2133 ◽  
Author(s):  
Santosh Kapuria ◽  
Bhabagrahi Natha Sharma ◽  
A. Arockiarajan
Keyword(s):  
Piezoelectric Transducer ◽  
Stress Transfer ◽  
Dynamic Shear ◽  
Shear Lag ◽  
Shear Lag Model ◽  
Lag Model
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