Fracture Behavior Of Cracks Research Articles

Online Measuring Method of Interlaminar Cracks of Laminated Composite Based on Image Processing Technology

In order to obtain a real-time interlaminar crack fracture behavior of the laminate composites, in this paper we propose a method of extracting and measuring of interlaminar crack of laminated composite materials based on 2D image analysis via the Matlab software. Extracting the main crack image were conducted using the Matlab script including four different algorithms: the binarization, region growing, morphological, and skeleton thinning, and then a main interlaminar crack image with 1 pixel width were obtained. The length of the main crack was calculated through the sum of pixels of the skeletonized object. The calculated result was closed to the measured result, and the difference between the calculated value and measured value was 0.2%, which can prove the accuracy of the method in present work. The proposed method is of high precision, with strong anti-inference ability and experimental data is stable and reliable, which is helpful to study the crack propagation behavior of laminated composite materials.

Fracture Behavior of HIP Bonded C1100 Copper and SS400 Mild Steel

The fracture behavior of cracks in the vicinity of a HIP diffusion bonded interface between JIS designation SS400 mild steel and C1100 copper was investigated. The cracks were oriented parallel to the diffusion bonded interface and a tensile load was applied in a direction perpendicular to the interface for a range of test temperatures from 20°C to -180°C. Material dissimilarity led to a complex mode of crack opening, and failure occurred either at the crack or at the material interface depending on the position of the crack relative to the interface and the test temperature. The differences in behavior were investigated using a three-dimensional finite element analysis (FEA). The strain energy density criterion was applied to predict the occurrence and direction of crack propagation by lowstress brittle fracture at extremely low temperatures. It is suggested in this paper that fracture initiation at the interface edge can be predicted based on the total strain energy density in that region.

Correction for Wang and Jiang, Fracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditions

You have accessMoreSectionsView PDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmail Cite this article Wang X. D. and Jiang L. Y. 2002Correction for Wang and Jiang, Fracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditionsProc. R. Soc. Lond. A.4583092http://doi.org/10.1098/rspa.2002.2004SectionYou have accessCorrection for Wang and Jiang, Fracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditions X. D. Wang X. D. Wang Google Scholar Find this author on PubMed Search for more papers by this author and L. Y. Jiang L. Y. Jiang Google Scholar Find this author on PubMed Search for more papers by this author X. D. Wang X. D. Wang Google Scholar Find this author on PubMed Search for more papers by this author and L. Y. Jiang L. Y. Jiang Google Scholar Find this author on PubMed Search for more papers by this author Published:08 December 2002https://doi.org/10.1098/rspa.2002.2004This article corrects the followingResearch ArticleFracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditionshttps://doi.org/10.1098/rspa.2001.0922 X. D. Wang and L. Y. Jiang volume 458issue 2026Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences08 October 2002AbstractCorrection for ‘Fracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditions’ by X. D. Wang and L. Y. Jiang (Proc. R. Soc. Lond. A 458, 2545–2560. (doi: 10.1098/rspa.2001.0922)).The Digital Object Identifier on p. 2545 should be 10.1098/rspa.2001.0922. Previous Article VIEW FULL TEXT DOWNLOAD PDF FiguresRelatedReferencesDetailsCited by Lang S (2005) Guide to the Literature of Piezoelectricity and Pyroelectricity. 23, Ferroelectrics, 10.1080/00150190500259707, 321:1, (91-204), Online publication date: 1-Aug-2005. Related articlesFracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditions08 October 2002Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences This Issue08 December 2002Volume 458Issue 2028 Article InformationDOI:https://doi.org/10.1098/rspa.2002.2004Published by:Royal SocietyPrint ISSN:1364-5021Online ISSN:1471-2946History: Published online08/12/2002Published in print08/12/2002 License: Citations and impact

Fracture behaviour of cracks in piezoelectric media with electromechanically coupled boundary conditions

Existing studies on slit crack problems have been limited mostly to the electrically impermeable and permeable crack models, which represent the limiting cases of the physical boundary condition. This paper studies the generalized plane problem of a crack in a piezoelectric medium, with the electric boundary condition along the crack surfaces being governed by its opening displacement. The theoretical formulation of this nonlinear problem is based on the use of Fourier transforms and the solution of a system of integral equations, which are solved using Chebyshev polynomials. The analytical solution of the problem clearly shows the transition between permeable and impermeable models with increasing crack opening. Depending on the applied mechanical and electric loads, different modes of crack deformation are predicted and discussed.

Non-overlapping conditions for crack face displacement of anisotropic bodies

Crack tip stress and displacement fields are useful for studying the fracture behavior of cracks in both isotropic and anisotropic materials. Under certain boundary conditions, crack surfaces could overlap, a condition that could be more prevalent for the anisotropic case as compared with isotropic materials. Conditions can be derived for different loading conditions and material properties such that overlap of the crack faces would not occur.

Sub critical crack advance vs. impact fracture on high impact polystyrene with different second phase volume contents and structures

Also for polymers, many fractures in service occurs after a period in which an existing crack has propagated in a sub-critical manner, while the laboratory tests are mainly concentrated on impact fractures. Aim of this paper is then to investigate the sub critical fracture in some high impact polystyrene (HIPS) materials with different second phase volume fraction and particle size and to compare it with the outcomes of impact Fracture Mechanics experiments. Large differences in the results of the two mechanical test procedures are evidenced: the materials behaviour is then examined from the structural point of view and an interesting case of interfacial failure, which disappears at high strain rate, is attested on some HIPSs by means of different techniques, i.e. electron microscopy, nuclear magnetic resonance spectroscopy and dynamic mechanical spectroscopy, indicating that the slow crack fracture behaviour can be influenced by parameters that do not affect ordinary mechanical tests.

Fracture behavior of cracks in ductile plates under monotonic mixed-mode loading

An experimental study of the early stages of ductile fracture was undertaken by using scanning electromicroscopy (SEM). The variation of several parameters influencing this type of fracture was introduced during the study of the preliminary blunting phase followed by the creation of the damaged ligament in front of the crack which resulted in the initiation of the slow propagation phase. This was achieved by changing the angle of obliqueness, α, of the edge cracks made in thin or thick plates of polycarbonate which exemplified cases where predominantly plane stress or plane strain conditions prevailed. The change of the angle α influenced drastically the value of the mixed-mode factor μ = K 11/K 1. The parameters studied were the crack-tip opening angle (CTOA), the damaged ligament in front of the crack face, the direction and orientation of the subsequent crack initiation and propagation and finally the variation of crack propagation and velocity at the early stage of slow crack propagation. Important results were derived from this experimental study which clarified various aspects of ductile fracture during the initiation of a new step of propagation of the crack.