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Article type: Cover
Pages
Cover1-
Published: July 31, 2000
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Article type: Appendix
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App1-
Published: July 31, 2000
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Article type: Index
Pages
Toc1-
Published: July 31, 2000
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Norihiro UENOYAMA, Genki YAGAWA, Minoru SHIRAZAKI
Article type: Article
Pages
1-2
Published: July 31, 2000
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In this paper, Free Mesh Method (FMM) was applied to moving boundary problems. FMM is a kind of meshless method based on the finite element method. In FMM, global equations can be constructed without element-node connectivity information, only if nodal coordinates and boundary information are given as input data. The Arbitrary Lagrangian-Eulerian (ALE) method was employed here. The present method was applied to a simple two-dimensional analysis.
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Jun IMASATO, Yuzuru Sakai
Article type: Article
Pages
3-4
Published: July 31, 2000
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This paper describes an Application of Meshless Method to 2 dimensional crack propagation problem. The Meshless Method, it is effective method to apply to problem with complextive curved crack path, because the stiffness matrix obtained by estimate each nodes without element mesh. In this study, the local approximation is defined by using Taylor series expansion with high order derivatives, and Nodal Integration is evaluated by using Voronoi polygons.
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Changcheng SHAO, Yasuhiro MATSUDA, Naoharu Hasagawa
Article type: Article
Pages
5-6
Published: July 31, 2000
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Atsuya OISHI, Shinobu YOSHIMURA, Genki YAGAWA
Article type: Article
Pages
7-8
Published: July 31, 2000
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This paper describes a new contact searching method using a hierarchical neural network. Generally, contact searching process consists of two phases : a global searching phase for finding nearest node-segment pair and a local searching phase for finding exact local coordinates of the contact point in the segment found. In the present method, a hierarchical neural network is utilized for finding the local coordinates of the contact point in the local searching phase. In this paper, the fundamental formulation of the neuro-based local contact searching method is described in detail and basic performance of the method is demonstrated through sample analyses.
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Tadao SHIMADA, Shoji MURAKAMI, Takao KANAMARU, Jyunichi OKUMURA
Article type: Article
Pages
9-10
Published: July 31, 2000
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This paper describes an automatic operating system with Neural Networks for a bulky-refuse shredding plant. One of the important technologies in the automatic operating system is the measurement, with an image processing unit, of the volume of raw materials. However, it is sometimes impossible to measure the material volume correctly only with the image processing unit, for example, in a dusty environment. As one of the solutions, we applied Neural Networks for the volume estimation, and have verified the advantage of using Neural Networks through a series of validation tests in a real shredding plant.
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Nagatomo TSUJI, Yoshitaka UMENO, Takayuki KITAMURA
Article type: Article
Pages
11-12
Published: July 31, 2000
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Atomic disorder near grain boundary influences property of material. In this study, stress and elastic coefficient near the Σ5 tilt grain boundary in alminium are analyzed by molecular statics simulation based on the Effective Medium Theory (EMT). Local stress and elastic coefficient within the range of 7Å from boundary differ from those in grain, though the averaged elastic coefficient in this range is almost the same as that of single crystal. The grain boundary consists of two kinds of atomic layers where elastic coefficient is different.
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Shuuichi NAKAZATO, Akito TAKASAKI
Article type: Article
Pages
13-14
Published: July 31, 2000
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An early stage of tensile behavior of Ni crystal containing a small amount of hydrogen was simulated by means of molecular dynamics. The total number of Ni atoms was 1800 and hydrogen atoms were located at the tetrahedral site (T-site) as well as the octahedral one (O-site) in the unit lattice. It is found that hydrogen at the T-site migrates to the O-site at an early stage of tensile test and the presence of hydrogen in the system enhances the crystal slip at a lower strain. Total number of hydrogen atoms and their location in the system also influence to the slip.
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Yoshinari HATANAKA, Shigenobu OGATA, Hiroshi KITAGAWA
Article type: Article
Pages
15-16
Published: July 31, 2000
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A sliding properties of {0110}, <0001> of β-silicon nitride are studied using the first principle molcular dynamics method (FPMD). The system was examined by means of molecular dynamics recently, and it has been proved that easy sliding occurs in this system and the sliding behavior is strongly dependent on rebonding process. Accordingly, we investigate the detail of the Si-N rebonding which happens in the {0110}, <0001> sliding by FPMD. The FPMD calculation is peformed to investigate the electric structure of Si-N bonds as well as energy, without relaxing atomic positions. Finally the result is compared with that of molecular dynamics in order to inspect validity of the potential that was suggested to represent two- and three-body interatomic energy by Vashishta.
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Tadao FUKUTA, Yasuhiro AKAHOSHI, Shoji HARADA
Article type: Article
Pages
17-18
Published: July 31, 2000
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Takashi IIZUKA, Toshihiko HOSHIDE, Akira ONODA
Article type: Article
Pages
19-20
Published: July 31, 2000
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Relation between pore formation and hardness of Al thin film sputtered on Si substrate is investigated by molecular dynamics simulations. Vacancy ratio and size introduced in thin films are varied and these effects to hardness are discussed. Effects to packing ratio and residual stress are also investigated. As vacancy ratio is increased, Both packing ratio and compressive stress which exist in the film without vacancy are decreased. As for hardness, films are softened because of the decrease of residual compressive stress. However, it is also implied that distribution and size of pore also influence film hardness. These results qualitatively agree with experimental results.
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Tomoo KAYABA, Yoshio HAMADA, Masumi SAKA
Article type: Article
Pages
21-22
Published: July 31, 2000
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The single crystal diamond film has been drawn attention for new material such as the electronic devices used in higher temperature. So it is important to understand a mechanism of diamond nucleation on silicon substrate by Chemical Vapor Deposition (CVD) method, but the mechanism has not yet been established because of the difficulty of the observation. Fundamental process of the nucleation of the diamond consists of both the adsorption and the reflection of carbon atoms to the silicon substrate. The details of both phenomena have not yet been clear. In this paper, in order to solve fundamental process of the nucleation of the diamond, molecular dynamics simulation of the adsorption of the carbon atom is conducted. The adsorption phenomenon affected by the velocity and angle of incidence of the carbon atom is presented here. It is shown that the adsorption phenomenon is independent of the velocity and the angle of incidence.
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Yoko SAITO, Naoya SASAKI, Hiroshi MORIYA, Shingo NORO
Article type: Article
Pages
23-24
Published: July 31, 2000
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Molecular dynamics simulation was used to investigate wear models of frictional sliding between a pin and a graphite like carbon film containing nitrogen. In this study, we developed advanced Tersoff interatomic potential describing N-N bond and C-N bond respectively. We examined the influence of content of nitride on the dynamics properties of wear atoms. These simulations show that wear is minimized when about 20 percent nitrogen is added. Also, simulation results correspond with the experimental results qualitatively.
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Kazuhiko SASAGAWA, Masataka HASEGAWA, Manabu YAGI, Masumi SAKA, Hiroyu ...
Article type: Article
Pages
25-26
Published: July 31, 2000
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Tomotsugu SHIMOKAWA, Akihiro NAKATANI, Hiroshi KITAGAWA
Article type: Article
Pages
27-28
Published: July 31, 2000
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Molecular dynamics simulations have been performed to investigate a role of grain boundary region in deformation of nano-polycrystalline material. For three Al nano-crystal models with different mean grain sizes which consist of nearly 600,000 atoms, we perform uniaxial tensile test in two different tensile rate. As the result, the smaller mean grain size is, the smaller the value of the maximum load is. This mechanical property is against the Hall-Petch relation. Equivalent strain in atomic scale shows that the behavior of grain boundary region have a decisive role for many macroscopic properties bacause of large proportion of the grain boundary compared to ordinary porycrystalline materials.
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Masato NAITO, Kisaragi YASHIRO, Yoshihiro TOMITA
Article type: Article
Pages
29-30
Published: July 31, 2000
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A molecular dynamics simulation of tension is conducted on a single crystalline Ni-based superalloy with cuboidal γ' precipitates. The results indicate that a partial dislocation loop nucleated at an edge of cubic γ′precipitate divides into a pair of partial dislocations on a γ/γ′interface of neighboring γ′precipitate.
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Ryuichi TARUMI, Akio OGURA, Masayuki SHIMOJO, Kazuki TAKASHIMA, Yakich ...
Article type: Article
Pages
31-32
Published: July 31, 2000
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A molecular dynamics simulation was performed to investigate the structural changes during a plastic deformation process in an amorphous metal. An amorphous model is constructed from Ni atoms interacting via a Morse-type pairwise additive potential. At shear stresses below 2.4GPa, shear strain increased linearly with increasing shear stress. However, large shear deformation occurred when shear stress reached 2.8GPa. During this shear deformation, crystallization was observed in the model. The crystalline phase had an fcc structure which had an orientation relationship, i.e., the shear direction and a (111) plane are parallel. This relationship was consistent with our experimental study on a Ni-P amorphous alloy.
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Ryosuke MATSUMOTO, Hiroshi KITAGAWA, Keiko NAKATANI, Akihiro NAKATANI
Article type: Article
Pages
33-34
Published: July 31, 2000
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Large scale molecular dynamics simulation are performed to examine the fracture mechanism of an amorphous metal. Crack propagation behaviors in a model amorphous material made from FS-potential for Fe atom are analyzed for a thick-plate model with periodic structure and a thin-plate model. In the former model, being promoted by development of band-like shear deformation emanating from the crack tip and density decrease in the crack front region, smooth crack blunting with round tip proceeds. On the other hand in the thin plate model, after slight blunting, the crack sharpening proceeds, which is accompanied by a narrow damaged region in the crack front where a void nucleates thereafter. And coalescence of the crack and void drives further crack advance. Fracture in amorphous metal is revealed to be ductile locally but brittle-like macroscopically, which are quite different from those in the materials with crystalline structure.
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Yoshitaka UMENO, Takayuki KITAMURA, Kuniyuki NAKANISHI
Article type: Article
Pages
35-36
Published: July 31, 2000
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Molecular dynamics simulation using EMT is conducted in order to clarify the mechanism of tensile deformation of Al nano contact. The tensile strain is applied to several models with different crystalgraphic directions (Model (a) : [001], Model (b) : [011], Model (c) : [111]). In the early stage of deformation, the nano contact is elongated by slips on {111} plane. In the case of Model (a), slips on the same direction form necking and twin boundaries. In Model (b) and Model (c), slips in the different directions, which occur at the same time, intersect each other and disarrange the crystal structure there. These cause the deformation concentration. The deformation at the late stage is brought about by not the slip but the twist of necking region.
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Takashi Ishiba, Moritaka Hida, Akira Sakakibara
Article type: Article
Pages
37-38
Published: July 31, 2000
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Molecular dynamics simulation of nickel single nanocrystal in the uniaxial tensile and compressive deformation is performed using three kinds of potentials (EAM, Finnis Sinclair and Morse potential) to investigate the effect of potential on the deformation mode. The effect of potential was observed under tensile loading; crystallinity was broken down in the case of Morse potential, phase transformation (fcc→hcp) was caused in the case of FS potential, and (111) [101] slip was observed in the case of EAM potential. Similar development of twin deformation, (111) [112], was observed in all the cases under compressive loading.
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Kenichi SAITOH, Masao KOMAYA, Takehiko INABA
Article type: Article
Pages
39-40
Published: July 31, 2000
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A multi-resolution (MR) molecular dynamics (MD) method is developed for collision and coalescence processes of nano-size metallic atomic clusters. As an interatomic potential between copper atoms, Lennard-Jones model is used. Ordinary molecular dynamics portion, in which interaction between individual atoms is important, is restricted to the region near the contact point. At the same time, translational motion of whole cluster is determined by the interaction between clusters. It is demonstrated that these two kinds of motion are represented by equations of motion, which are derived from the same Lagrangian for the total particles system with some assumptions. In contrast to ordinary MD simulation, the force acting on each cluster in MRMD simulation decreases during collision process, which is supposed to be caused by exclusion of atomic oscillation in the rigid body region.
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Tetsuya KUGIMIYA, Satoshi NAKAMURA, Yoji SHIBUTANI
Article type: Article
Pages
41-42
Published: July 31, 2000
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Tight-binding method (TB) lies between the very accurate but expensive ab-initio calculations and the fast but limited empirical methods for description of atomic-level materials behaviors. As the size of system involved becomes larger, the more inevitable scaling a solved hamiltonian matrix down is. The number of operations required to diagonalize a hamiltonian matrix is proportional to the cube of the system size. Therefore, several algorithms of O (N) scaling have been developed. In the present paper, we demonstrate the improvement of tight-binding molecular dynamics calculation by the density matrix algorithm, compared with standard diagonalization method.
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Yoshihiro OCHIAI
Article type: Article
Pages
43-44
Published: July 31, 2000
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Linear stress analysis without body force can be easily solved by means of the boundary-element method. Some cases of linear stress analysis with body force can also be solved without a domain integral. However, domain integrals are generally necessary to solve the linear stress problem with complicated body forces. This paper shows that the linear stress problem with complicated body forces can be solved approximately without a domain integral by the triple-reciprocity boundary element method. In this method, the distribution of complicated body forces is interpolated by integral equation. A new computer program is develoed and applied to some problems.
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Hiroyuki KISU, Guiming RONG, Yoshihiro KONDO
Article type: Article
Pages
45-46
Published: July 31, 2000
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Hiroyuki KISU, Yoshihiro KONDO, Guiming RONG
Article type: Article
Pages
47-48
Published: July 31, 2000
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Osamu OKUDA, Yoshihiro Nishimura, Hideki NAGAI
Article type: Article
Pages
49-50
Published: July 31, 2000
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This paper describes briefly the formulation by the homogenization method to determine the equivalent elastic modulus of three-dimensional composite materials by considering the microstructure. The reinforcement and matrix of unit cell of multiphase polymer are modeled using the hexahedral finite element discretization and the homogenized elastic constant is numerically analyzed. The effects of the arrangement of reinforcement are discussed.
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Hiroshi OKADA, Shutatsu FUJITANI, Yasuyoshi FUKUI, Noriyoshi KUMAZAWA
Article type: Article
Pages
51-52
Published: July 31, 2000
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A homogenization method for beam/bar structure is derived and presented in this paper. The beam/bar structure is assumed to be made of repeating unit cells, whose sizes are much smaller than the length of the structure. The macroscopic deformation of beam/bar structure is described based on the Euler-Bernoulli beam theory and on the torsion of circular shaft. Perturbed displacements are computed by three dimensional finite element method for unit cell, representing a unit of periodic structure. Procedures to calculate the perturbed displacement and an expression for effective stiffness of structure are presented. A few numerical examples are presented to demonstrate the validity of present method.
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Shigeo TAKEZONO, Hirofumi MINAMOTO, Masataka MITSUYAMA, Motoyuki NAGAI
Article type: Article
Pages
53-54
Published: July 31, 2000
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Impacts of two spheres are generally characterized by coefficients of restitution. The coefficient of restitution is originally defined for the point mass while actual spheres have the size and deform in impact. This paper intends to discuss the effect of plastic deformation on the coefficient of restitution. The elastic plastic analyses of the impacts of two spheres are carried out for the various impact velocities by using the ANSYS code. The variations of the coefficients of restitution with the impact velocities are simulated. Then the coefficients of restitution are presented as the function of the impact velocities.
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Yuzuru SAKAI, Musop SON
Article type: Article
Pages
55-56
Published: July 31, 2000
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Akiyuki YANAGIMOTO, Hiromasa ISHIKAWA, Katsuhiko SASAKI
Article type: Article
Pages
57-58
Published: July 31, 2000
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In this paper, FEM analysises of microelectronics solder joints subjected to cyclic thermal deformation were conducted. Pb free solder alloys (Sn-3.5Ag-0.75Cu) were chosen for the analysis, because of the regulation of using Pb/Sn solder alloys in near future. Results of Pb free solder alloys were compared with that of Pb/Sn solder alloys. Elasto-plastic, elasto-creep, and elasto-plastic-creep analysis were employed in this paper. As a result, it was found that the equivalent stress of Sn-3.5Ag-0.75Cu is much larger than that of Pb/Sn solder alloys, and that the elasto-plastic-creep analysis takes advantage of the simulation both of Pb free and Pb/Sn solder alloys.
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Yasumi KITAJIMA, Satoru SHIBATA
Article type: Article
Pages
59-60
Published: July 31, 2000
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NUPEC and USNRC have been jointly sponsoring "Structural Behavior Test" as Sandia National Laboratory (SNL) in "Cooperative Containment Research Program" to investigate the response of representative models of nuclear reactor containment structure due to internal pressure loading beyond the design basis accident and to establish analytical prediction methods. The Steel Containment Vessel (SCV) model test was carried out at SNL on December 11-12 1996. In this report, we applied the analytical prediction method to an actual scale SCV model under the Severe Accident (SA) condition.
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Masaru HIGA, Ikuya NISHIMURA, Hiromasa TANINO, Yoshinori MITAMURA
Article type: Article
Pages
61-62
Published: July 31, 2000
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Fatigue failure of the acrylic cement and resulting disruption of the bone-cement interface can limit the long-term clinical success of the cemented artificial hip joint. In order to overcome this problem optimal shape design prosthesis is required. This study describe a result of the design shape analysis (DSA) and the numerical shape optimization whereby the finite element method is used to determine optimal shape for the femoral stem of hip prosthesis in order to minimize the maximal value of the 1^<st> principal stress at the cement mantle.
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Masahiro TAKANO, Shiro TAKADA, Hiroshi MURAKAMI, Masashi YUI
Article type: Article
Pages
63-64
Published: July 31, 2000
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The trend of power transformer is large capacity and high voltage. This leads to the increase of the transformer's size and weight, and meets with other problems such as limitations from transportation. Thus, the demand for the lightweight design is in urgent. This paper presents a development of lightweight design of the shell type transformer's tank by structural optimization. Both an optimality criteria technique and genetic algorithms are used in order to perform optimization efficiently. It is shown that the weight is reduced up to 15% while the strength request is ensured in the optimum design compared with in the original design by use of these techniques, which indicates that these techniques are effective in the lightweight design of the shell type transformer's tank.
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Yuki ITOH, Yasuji TSUBAKISHITA, Akira SADAMOTO, Yoshinori MURAKAMI
Article type: Article
Pages
65-66
Published: July 31, 2000
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The transmission characteristics of a duct with eccentric three slits are numerically analyzed and measured with various slit's size. The three-dimensional structure of sound field in the duct is computed with a finited difference method. The present results show that effective frequency range on sound attenuation becomes to be wider, compared with the case of a single eccentric slit or that of concentric three slits. The computed transmission coefficient give excellent agreement with our experimental data.
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Yoshihiro KAWAMOTO, Masahiko UEKUSA, Yoshiaki TERUMICHI, Masumi KATAOK ...
Article type: Article
Pages
67-68
Published: July 31, 2000
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The interesting phenomenon is the segregation in the behavior of objects in the rotation barrel. The segregation may be shown, when rotation barrel that filled 2 kinds of objects of different material of size is rotated. Then, it is uncertain for whether it shows this segregation, when the barrel in which rotating center is eccentric is also filled with objects. This study examines and compares the behavior of the 2 kinds of filled objects which are different material or size in the rotation barrel with the eccentricity from experiment and simulation by DEM (Discrete Element Method). As the result, the segregation was shown when it was also eccentric. However, it became difficult to segregate with the increase of the eccentricity.
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Shun OKAYAMA, Toshiro MATSUMOTO, Masataka TANAKA
Article type: Article
Pages
69-70
Published: July 31, 2000
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Wenwei GU, Genki YAGAWA
Article type: Article
Pages
71-72
Published: July 31, 2000
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The three-field mixed form based upon the Hu-Washizu principle is introduced to 3 dimensional Free Mesh Method (FMM). We call this new kind of FMM as Mixed 3-D FMM. The Mixed 3-D FMM passed a patch test which is a block under uniform tension. It is then applied to stress analysis of a cantilever beam under bending, and remarkable improvement of accuracy compared to displacement based FMM is shown.
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Masataka TANAKA, Wen CHEN
Article type: Article
Pages
73-74
Published: July 31, 2000
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Osamu Yuzawa, Takahumi Aono, Tomonobu GOTO, Yasunari TAKANO
Article type: Article
Pages
75-76
Published: July 31, 2000
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The present paper deals with experimental and computational studies for stress waves induced in elastic solid by a shock wave in gas. For shock-tube experiments, solid models made of transparent acryl resin used, and shock waves are propagated to the model. The schlieren technique is employed to visualize shock waves in gas as well as stress waves in transparent solid. Numerical simulations are carried out for stress waves inside the solid model and for reflected-shock waves outside the model. Good agreement is obtained between experimental and computational results.
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Tomoaki TSUJI, Naotake NODA, Masaki MAKINO
Article type: Article
Pages
77-78
Published: July 31, 2000
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Formation of a void is a considerable feature for a number of engineering materials, because failure by coalescence of the voids is an important fracture mechanism in ductile solids. There are some theoretical solutions of the void formation for a nonlinear elastic solid. On the other hand, it is important to study microscopic void formation, in order to consider the initiation of the void. In this paper, we simulate some void formations by using Molecular Dynamics and FEM. The cylinder with an atom defect is constructed with nickel atoms and is subjected to the hydrostatic tensile load by using Molecular Dynamics. As the load exceeds, sudden appearance of the void is observed and it develops. The same simulation is proceeded by FEM for nonlinear elastic solid. In the simulation, the mechanical properties, which are given by the potential function of the Molecular Dynamics, are used. The behaviors of the void initiation by the two methods, which are microscopic and macroscopic method, are compared to each other.
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Hidenobu IGAWA, Nao Aki NODA
Article type: Article
Pages
79-80
Published: July 31, 2000
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This paper is concerned with theoretical analyses of periodic arrays of cracks in solids under in-plane shear. We use proper unit regions, and take the complex stress potentials in Taylor series expansions satisfying the external loads and displacements at the outer edges of the unit regions. We also take Body Force Method (BFM) satisfying the traction-free conditions of the crack edges. Numerical calculations are performed for various combinations of the parameters.
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Jinquan Xu, Yoshiharu Mutoh
Article type: Article
Pages
81-82
Published: July 31, 2000
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Ryusuke KAWAMURA, Masashi MORIKAWA, Yoshinobu TANIGAWA
Article type: Article
Pages
83-84
Published: July 31, 2000
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This study is intended as an optimization of material composition in nonhomogeneous hollow sphere which has two-dimensional nonhomogeneous material properties in the radial and meridian directions and is subjected to an axisymmetric heat supply. Numerical solutions of temperature change and axisymmetric thermal stress under the steady state are obtained for nonhomogeneous hollow sphere which has two-dimensional nonhomogeneous material properties by making use of finite element method. As an illustrative numerical result, optimal two-dimensional material composition is found for the functionally graded hollow sphere so as to minimize the ratio of thermal stress under the steady state to strength of material.
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Susumu YAMASHITA, Hideo KOGUCHI
Article type: Article
Pages
85-86
Published: July 31, 2000
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In three-dimensional joints, stress concentration is generated by the difference of material properties at the interface edge, and the generation of cracks and strength degradation may be caused. In this study, stress singularity for the bonded structures of metal and ceramics observed frequently in electronic components is analyzed considering thermal strain. And the eigenvalue analysis based on the formulation of finite element method is used for calculating the order of stress singularity. Concretely, thermal displacement and thermal stress distribution near the stress singular field is investigated in the three-dimensional bonded structure for uniform temperature change.
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Tomoyoshi NINOMIYA, Masayuki ISHIHARA, Naotake NODA
Article type: Article
Pages
87-88
Published: July 31, 2000
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A functionally graded materials which decrease thermal stresses have been developed for structural components and/or mechanical elements in fields such as nuclear, aircraft and space engineering. In this research, the steady thermal stress distribution of a plate of functionally graded material with the homogeneous layers on both surfaces is analyzed. The main theme of this subject is to maximize the safety factor in a plate of functionally graded material with the homogeneous layers.
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Masataka TANAKA, Toshiro MATSUMOTO, Shoji OIDA
Article type: Article
Pages
89-90
Published: July 31, 2000
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Hideaki NOZAKI, Mishio KAWASHITA, Minoru TAYA
Article type: Article
Pages
91-92
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
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In this paper, the elastic field in an infinite elastic body containing a polygonal inclusion with uniform eigenstrains is investigated. Exact solutions are obtained for the stress field inside and outside a fully general polygon, i.e., an arbitrary bounded region of two-dimensional space with a piecewise linear boundary. Numerical examples are presented for the stress field inside and outside a regular polygonal inclusion. Then the special properties of strain field in a regular polygonal inclusion reported in the previous paper (H. Nozaki and M. Taya, ASME J. Appl. Mech., 64 (1997), 495-502) are discussed in detail. Finally, scattering cross sections of a regular polygonal inhomogeneity and static average stress inside a regular polygonal inhomogeneity are calculated by BEM and these values are found to have a similar property with the strain field in a regular polygonal inclusion.
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Sei UEDA, Tatsuya MUKAI
Article type: Article
Pages
93-94
Published: July 31, 2000
Released on J-STAGE: August 01, 2017
CONFERENCE PROCEEDINGS
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The plane elasticity solution is presented in this paper for the crack problem of a layered medium. A functionally graded interfacial region is assumed to exist as a distinct nonhomogeneous transitional layer with the exponentially varying elastic property between the dissimilar homogeneous surface layer and the substrate. The surface layer contains a crack perpendicular to the boundaries. Fourier transforms are used to formulate the problem in terms of a singular integral equation. The main results presented are the variations of stress intensity factors as functions of geometric and material parameters of the layered medium.
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