The purpose of this study is that development of welfare machine which type of human conmforts byimprovement of lubrecating properties in the human lifespeed area by using porous film that is hard and have many holes on the film and mixed grease. Results are as follows. (1) Conparing uncoated and porous in the torque tests, differenses weren't gain in torque property in each grease. (2) The hybrid film was created by inpregnation of micro-porous of porous film with MoS_2 on each grease. This is very affective against redusing torque in very-slow-speed-range. (3) By analysing grease flow on spinel film, thin grease film was created on the porous film. By this, increasing torque by rough surfase on spinel film could prevent. (4) Examining containing rate of MoS_2 in porous film, increasing containing rate of MoS_2 brings about redusing torque in very-slow-speed-range on each grease. (5) Depending on the hyblid film, redusing torque and improvement of lubrecating propertiesin the human lifespeed area were obtained relative to compositing spinel film and mixed grease.

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In the future, the aging society will come in Japan. So it will be almost impossible to nurse to old people. Recently, the welfare equipment has been developed to support of independence life and barrier free. However, they have not been designed with the sensitivity and performance evaluation of a walk support machine is not performed. Therefore, we will sense the discomfort when we use the welfare equipment. In this study, we tried to develop the buggy cane suitable for the operation of human. Concretely, study contents are as follows; (1) Design of the buggy cane of a trial product. (2) Outline design of walking analysis system. (3) Comparison of the walk data of a youth and elderly people and reduction to improvement of a walk support machine, we tried to develop the "wonderful" and "comfortable" buggy cane.

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In order to make low the friction coefficient between the flange parts of a railway wheel and which ride and cause uphill derailment, it considered giving a DLC leather film However, this DLC leather film is not used in the place of high load and high-speed rotation. Then, the destructive mechanism of a leather film was solved in this experiment, and it aimed at tying to creation of a future leather film. And although a friction coefficient can reduce a DLC leather film by having composite as an obtained result, the durability of a leather film is missing. Therefore, a leather film needs to be improved.

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Recently, the thinning of the plastic product is advanced. But many problems such as the increase of inside residual stress and the lowering of the mold shrinkage rate in the metal mold by high-speed and high-speed filling by injection molding, the increase of the mould release force in the mould release occur. And, the increase of the mould release force causes the mould release bad, and deformation, cracks, injury of the product, etc. have arisen. In this study, we aimed at reduction in the problem about mold release by surface modification. Especially, we noticed influence of surface modification on friction phenomenon and adhesion phenomenon of the interface between metal and plastic

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Viscosity-pressure-temperature relation of polyalphaolefin were determined at a pressure up to 0.5GPa and a temperature between 30 and 90℃ with a falling ball type viscometer. Then, the traction curve was determined at low-pressure region with a disk-on-ball type EHD tester. The calculated results based on the simplified Newtonian solution taking into account the shear heating were not in good agreement with the measurements in the non-linear region of a traction curve.

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Wear properties were evaluated for some synthetic lubricants including polyalkylene glycols polyolesters, perfluoropolyether and polyalphaolefin with an aluminum alloy pin on cast iron disk type tribometer in HFC-134a refrigerant environment, in which the friction behavior and contact potential were also determined. The anti-wear performance revealed the boundary lubricating effect depending upon the solubility of gas in the oil. That is, comparing the results between 100kPa, and 500kPa, the wear resistance for each lubricant was improved at higher gas pressure except for polyalphaolefin immiscible with refrigerant.

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Oil film formability of oils containing polymer was studied with an ultra low speed disk-on ball type EHL tester, where conventional polymethacrylate and dispersant type polymethacrylate were employed. As the rolling speed is increased, the oil film thickness for the polymethacrylate containing oil follows the theoretical prediction based on the base oil. On the other hand, oil film thickness for dispersant type containing oil deviates upward from the prediction line with increasing rolling speed. It is inferred that adsorption of polymer on the surface affect film the thickness at the low speed.

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Traction curves were determined for a synthetic naphthene with a disk on ball type EHL tester. As the slide/roll ratio was increased, the coefficient of traction linearly increased, and then gradually decreased after reaching the maximum. The calculated results based on the thermal elastic-plastic solution proposed by Tevaarwerk were compared with the measurements, in which the limiting shear stress was expressed as a function of pressure and temperature. The thermal elastic-plastic solution showed more rapid decline compared to the measurements in the thermal region. This implies that further improvement of the thermal treatment of the EHD oil film is necessary.

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The mechanical properties of a Copper electroplating film and Copper bulk material are measured using a Nanoindentation test. This lating film was an amorphous substance (amorphous) after it left it for 24 hours or more in the room temperature, and it became a result by Koike et al. and a different result. The hardness of the copper plating film has lowered overall by about 20% compared with the bulk material. It is thought that hardness lowered to the hardness of the copper plating film overall because hardness including this pore.

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Nanoindentation tester had been made which had a loading system with a displacement-controlled PZT actuator. Vibration amplitude of the tester was a half of that in a load controlled tester. Loading curves measured at some loads were nearly a quadratic curve which was theoretically derived for the elastic indentation of axisymmetric indenter. In a nanoindentation test at 100mgf applied load, the penetration depth of the displacement controlled tester was 12nm larger than that of a load controlled tester, where as penetration depth values measured at 10gf by using both the testers were nearly same.

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Railway wheel is carried out film coating for prevention of "climbing derailment". Properties of DLC (Diamond Like Carbon) film are low friction and high hardness. DLC film showed good film properties in the test piece level. But, adhesion in DLC film is not good. Thus, we made internal layer between substrate and DLC film, and adhesion improved. This time around, this hybrid surface treatment DLC haven't used, at first we investigated effectiveness of DLC film on friction and wear properties. After, we considered the different of adhesion by the different of internal layer. We also analyzed loading stress by finite element method (FEM) analysis.

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The diamond-like carbon (DLC) films were deposited on Si wafers using different techniques such as a RF plasma CVD, a hot filament plasma CVD, and a plasma based ion implantation. Their friction and wear properties were evaluated under water and air environments using a ball-on-disk type reciprocating friction tester. The friction coefficient and wear in water were superior to those in air, when sliding against SiC ball. With SUS440C ball, the friction coefficient was affected by the effect of deposition techniques, although wear was less affected.

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Three types of DLC films, pure DLC, F-containing DLC, and Si-containing DLC film, were deposited on a WC-Co substrate by a plasma-enhanced CVD technique. Friction and wear properties were determined using a ball-on-plate type reciprocating friction tester in water, comparing the water results to those in ambient air. The friction coefficient of DLC and F-DLC films in water was considerably lower than that in air. With Si-DLC, the friction was almost the same level in both water and air, and was less than 0.1. The specific wear rate of films in water was much smaller than that in air and varied around the low level of (10)^<-8>-(mm)^3/Nm in water. With DLC and F-DLC films, the transferred amount of material on the friction surface of a mating ball was larger in a water environment than that in air. With a Si-DLC film, the difference in the transferred amount when exposed to either the water or air environment was small.

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Tribological properties were studied for rapeseed oil, polyolesters and mineral oil with an aluminum alloy in on disk type tribometer, by which the wear amount, the coefficient of friction and the contact potential relating to the formation of boundary film could be simultaneously detected during the run. For rapeseed oil the friction behavior was high with irregular fluctuation and the wear amount drastically increased during the run. On the other hand, the coefficient of friction for polyolesters was low level throughout the run, and the initial wear behavior followed by wear in the steady state was observed.

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Recently, extension of a long grease-up interval is desired in the slide axle hole used under high pressure and low-speed rocking of an oil pressure shovel front part etc. Then, by using the sintering alloy bush which include high viscosity-oil, the frequency of the maintenance between pin and bushes was decreased. However, it was common to have used SUS304,SPCC, etc. for a thrust washer before. Then, when authors added fluoride in high hardness urethane, application in a thrust washer part was attained and that of generating of unusual wear reduced. In this report, the performance under the abrasive environment which is one of the friction wear characteristics is introduced.

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The hard layer on the steel surface is formed by depositing aluminum thin film on the steel, diffusing aluminum into the steel, and nitriding. However, significant thermal deformations are formed on the specimen surface by performing this process. Therefore a method which achieves quenching, tempering, and shape correction was attempted before the above-mentioned process. We examined the wear characteristics for surface modified alloy tool steel made by use of the above processes with varying aluminum film thickness. Excellent resistances to the abrasive wear at an aluminum film thickness of 2.0μm are obtained.

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While by which the screw is used for almost all apparatus, however a screw achieve the duty as a conclusion object There are also many problems, such as fatigue destruction of a bolt and slack of a screw, and those problems are solved. Its attention is paid to the slack of a screw in, book research by which many researches are made from viewpoints, such as optimization of form, in order to carry out.. which gave DLC and MoS2 tunic to the washer which are some screw conclusion objects this time which finds out peculiarity at the point which tries problem solution by surface Modification, loosened by control of a friction coefficient, and aimed at the improvement in question-at that time, the focus was united with the influence of the tunic characteristic exerted on a screw conclusion object, and it inquired in detail.

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In this study, we present a numerical method simulating blood flow. The method uses FDM for continuum blood plasma and DEM for discrete erythrocytes and analyzes the blood behaviour by evaluating interactions between plasma and erythrocyte. In order to confirm the validity of the method, we perform the blood flow simulation of two-dimensional straight and bending blood vessels and compare velocity profile with experiment result.

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In this study, we present a new numerical method to quantitatively analyze the error of numerical solutions by using the adjoint sensitivity analysis. If a reference case of typical parameter is once calculated with the method, no additional calculation is required to estimate the results of the other numerical parameters such as more detailed solutions. Furthermore, we can estimate the exact solution from the results and can quantitatively evaluate the numerical error. Through a one-dimensional advection problem with source, we confirm the effectiveness of the method.

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This paper presents a new algorithm to obtain the trajectory plot of principal stress. From the result of the stress analysis by FEM (finite element method), "direction function" is calculated on each node of triangular mesh. Grid, a 3-dimensional array, is used to store the principal stress and the intersection location between iso-surfaces defined by three direction funcitions

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In the molecular dynamics simulation, the detection of close pairs of particles is the most time consuming process. We propose a new algorithm to detect the pair list for the simulation of rarefied gas. It gives O(n) time by means of counter sort of octree location code of multirecorded particles.

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Surfactant molecules form bilayer lipid membranes (BLM). The BLM undergoes a liquid-gel phase transition, and the surfaces fluctuate. The liquid-gel phase transition of BLM is known to be of first order and closely related with internal degrees of freedom of the amphiphilic molecules. We study shape fluctuation phenomena of a model of BLM by Monte Carlo simulations. We find that the shape fluctuation transition of the model of BLM is not influenced by the internal degrees of freedom when the BLM is in the gel phase.

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A cold moderator using liquid hydrogen is one of the key components in a MW-scale spallation target system, which is cooled down by using a impinging jet flow. Flow visualization experiments with a simulated moderator vessel with cylindrical configuration were carried out in order to clarify flow patterns in the cold moderator vessel, which showed jet induced flows such as recirculation flows and stagnant regions. Analytical results of velocity distributions obtained with a standard k-ε turbulent model agreed well with experimental results obtained under the hight and diameter ratio (h/D) of 1.0. Also, analytical heat transfer coefficients on the vessel bottom were predicted in the case of the ratio (h/D) of 1.0.

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A cold moderator using liquid hydrogen is one of the key components in a spallation target system, which directly affects the neutronic performance both in intensity and resolution. Hydraulic analyses for a decoupled moderator were carried out by using low-Reynolds-number k-ε two-equation turbulence models. : linear and 3rd order nolinear models. Analytical results were compared with experimental results obtained with a simulated decoupled moderator vessel. Analytical results of average velocity distributions could predict the flow patterns show in the experiment. However, it is necessary to use turbulence models improved on the Reynolds stress component.

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Turbulent combined convection between vertical parallel platesis simulated numerically using two-equation turbulence models for both the velocity and temperature fields. The purpose of the present paper is to analyze the transport phenomena affected by buoyancy because they have not been discussed empirically owing to the difficulty of the measurement. In particular, the behavior of turbulent Prandtl number has not been investigated numerically and empirically. Therefore, in this paper, the turbulent transport mechanism is analyzed by adding a buoyant effect to the transport equations and by modifying the damping functions. It is revealed that the modified model can simulate the heat transfer and fluid flow of turbulent combined convection. The effectiveness of the present model is confirmed by comparing the numerical result of DNS.

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In the JSNS facility, a liquid-hydrogen moderator is one of key components to keep high neutronic performance, which has to be designed so as to suppress neutron absorption in a vessel wall. Rational thickness of the moderator vessels made of aluminum alloy A6061-T6 was estimated under the design pressure of 2 MPa along the High Pressure Gas Safety Law. The integrity of the moderator vessel, especially, a neutron extraction surface, would be assured with 5mm-thick wall for a decoupled moderator (flat type vessel) and 4mm-thick for a coupled moderator (cylindrical type vessel). Necessary thickness of the welding line were also decided since the moderator vessel has to be fabricated by welding upper and bottom parts which are formed by a precise shaving processing.

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Sintered material in the past study couldn't be applied to higher-output Power tools because the shortage strength. In this study we developed higher-strength sintered material, and applied to higher-output Power tools. There is a correlation between strength and density. Therefore from the side of the element of powder alloy and the technique of compacting gear this study was proceeded. By investigation from the both side, the newly developed material has achieved 0.2Mg/m^3 higher density and 30% higher strength level than the material based on the simple pre-alloy powder material.

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In nuclear fusion reactors, there is the development of high-performance plasma facing components in one of the large problems. Tungsten and CX-2002U were used as an armour material in this research, it was joined in metallurgical with a heat sink material (oxygen-free copper) having the cooling pipe structure, and the divertor simulation test body was produced. Moreover, for the produced test specimen, repetition heat load test was carried out and the heat-resistance, the thermal conductive characteristics and the stability of the joined part were evaluated. Consequently, in the repetition heat load test of 1000 times, the value of the maximum temperature of each part was almost fixed and there was no rapid change, since the stability of the divertor simulation test body was confirmed. However, because the rapid temperature rise of the tungsten simulation test body in the repetition heat load test of 300 times was generated at the surface, it is necessary to examine the connection method furthermore.

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Recent years, the miniaturization of Electric device is progressing quickly. In connection with it, the miniaturization is advanced also for the coil used for the contact part of a connector. But, internal strain generated at the time of slit working has been a problem. Moreover, typical C5191R-H and typical C2680R-H were used for the quality of the material of a coil. Then, it was made internal strain is changed into result stress and investigated. Consequently, the difference remarkable in result stress arose by material or working.

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Platinum is one of the typical precious metals, and, probably, has an image as an object for accessories. However, it is used for the field broad as an object for industry In this study, in three kinds of Pt alloy (Pure Pt, PtRh10%, T-1Pt), it examines for the purpose of the elucidation of the fatigue destructive mechanism in Pt alloy for industry, each destructive form is compared, and examined. Main results were follows; (1) fatigue strength of PtRh10% is 110MPa, of T-1Pt is 60MPa As opposed to the fatigue strength of pure Pt is 40MPa (2) Destructive forms were static ductility destruction in three kinds of Pt alloys. (3) The intergranular crack occurred only in PtRh10%. It was what is depended on the difference in the strengthening method.

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Though the platinum is one of the representative precious metals, the platinum has been used as an Industrial use material of the crucible for the glass melt recently. In this study, the fatigue reliability at elevated temperature of platinum alloy which was the industrial use material demonstratively was examined by the elucidation of fracture mechanism. Main results were follows; (1) S-N characteristics of the PtRh alloy was almost arranged in the straight line. And, the (10)^7-fatigue strength was 30MPa. (2) From the fractography using SEM, it was indicated that fatigue fracture mechanism was similar to the static destruction in the high stress side, on the other hand, it was effected by creep in the low stress side.

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The mechanical reliability of flexible printed circuits (FPC) was studied with an attention to the mechanical properties, of reinforcing and adhesive material, specimen which contain different mechanical properties. The main results were as follows. (1) It was admitted that the under bending life of FPC was notably influenced of super engineering plastics. (2) If the Young's modulus is too large, a under bending life will fall and If fracture growth is small, a under bending life will fall were admitted. (3) The super engineering plastics of reinforcement material to extend develop a FPC under bending life needed clear that what possesses uniform and big modification simultaneously with the size of the optimal Young's modulus

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The high polymer material, Polycarbonate (PC) was coated with DLC (Diamond Like Carbon) noticed as a hard film. PC has many excellent characteristics. DLC was coated by following 2 types processes (P-CVD/DLC/PC & IVD/DLC/PC), (1) Plasma-Chemical Vapor Deposition (P-CVD) (2) Ionic Vapor Deposition (IVD). Therefore, it is the research purpose that the evaluations of tribological properties for surfacemodified PC were experimentally carried out. From the experimental result, the friction evaluation shows that DLC coated PC markedly reduce the friction coefficient and wear compared to Virgin (uncoated) materials. Especially, IVD/DLC/PC had low frictioncoefficient and high adhesion further than P-CVD/DLC/PC. However, when film thickness was increased, as for IVD/DLC/PC, the friction coefficient rose in the early stage, and P-CVD/DLC/PC maintained the low friction coefficient.

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The industry of our country has accomplished remarkable development in all fields after the war. Although much of the latest technology was acquired now, a result which has an environmental problem. The production of monochrome which consider the environmental problem is greater importance to reexamine. Since especially lightweight-izing and efficient-izing attract attention as an effective means to environmental load reduction, the expectation for advanced features of lightweight material is great. Then, surface modification technology is positively advanced as material development which gives the highly efficient nature corresponding to each use.

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We investigated the effects of internal stress on electrical properties of transistors fabricated on single-crystalline-silicon substrates. The electrical current direction (channel direction) was set in the Si<100>direction instead of the conventional Si<110>directions. The stress was stepwise applied to single-crystalline silicon by using a four-point-bending method, and the drain-electrical-current change caused by the stress was measured. The measurement showed that the drain electrical current changed linearly with the tensile stress parallel or perpendicular to the channel direction. The drain current in negative channel transistors increased with the tensile-stress increase. On the other hand, the drain current in positive channel transistors decreased with the tensile-stress increase. The defference between<100>-channel transistors and<110>-channel ones is discussed.

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An interatomic potential applicable to strength analysis taking the effects of atomospheric influence into account is investigated. Properties (bond length, latice constants, and binding energy) of Si, O_2 H_2,H_2O, and SiO_2 are calculated by using the extended Tersoff interatomic potential function. It is found that the calculated values coincide well with the experimental values when the proper potential parameter values are used.

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High power spallation targets for neutron sources are developing in the world. Mercury target will be installed at the material and life facility in J-PACK, which will promote innovative science. The moment the proton beams bombard the target, pressure waves will be generated in mercury by thermally shocked heat deposition. Provided the negative pressure generates through its propagation in the mercury target, the cavitation erosion will make damage on the interface between mercury and target vessel wall. The pressure wave is imposed to mercury by using Magnetic IMpact Testing Machine, MIMTM, to evaluate the effect of input-power and repeated-frequency on the erosion damage. Additionally, the simulation of bubble dynamics is carried out to discuss the relationship between the life time of micro-bubble and the erosion damage.

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The effect of mechanical degradation in a long-term-operated component on the creep-and fatigue-crack growth rates was studied. Creep-crack-growth tests and fatigue-crack growth tests were performed on creep-pre-strained and cyclic-strained CrMoV rotor-steel specimens. It was found that under constant load, creep-crack growth rates, da/dt, of the creep-pre-damaged specimens were higher than those of virgin specimens. Another result showed that fatigue-crack growth rates, da/dn, of fatigue-pre-damaged specimens were higher than those of virgin specimens. The results suggest that the creep remaining lives and fatigue remaining lives of the mechanically damaged CrMoV rotor steel can be estimated by using C^*&ΔJ of the damaged material and the da/dt and da/dn values of the virgin material.

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In order to evaluate the low cycle fatigue and vibration behavior of Ni-based directionally solidified (DS) material, vibration analysis and low cycle fatigue tests were performed. As a result we could obtain the correct values of natural frequency by considering the material anisotropy. Young's modulus of directionally solidified material was smaller than conventional cast material. So the stress range also became smaller than conventional cast material under the same strain range. The fatigue strength of directionally solidified material was higher than conventional cast (CC) material.

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Al-Mg alloys have been regarded as one of the candidate materials for the storage tank of compressed hydrogen gas in fuel cell vehicles. Since the inner surface of the tank is exposed to the high pressure of hydrogen, hydrogen embrittlement of the materials for the tank might occur by hydrogen penetration. However, little knowledge has been obtained so far on this issue. In this study, to approach a final goal of elucidating how hydrogen penetration and diffusion in the material take place, hydrogen permeation behavior was investigated in 5083 aluminum alloy sheets in O condition by means of hydrogen microprint technique, that can visualize hydrogen atoms penetrating in one side of the surface, diffusing inside the sheets and finally arriving on the other surface, utilizing photographic reaction. The effect of plastic deformation on the permeation behavior was also investigated by applying uni-axial tensile load. In the specimen exposed hydrogen gas and simultaneously subjected to plastic deformation, hydrogen atoms were observed to be evolved at second phase particles.

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Recently, copper is replacing aluminum as the interconnect material in the Si-ULSI devices. Copper has lower electric resistance and higher resistance to EM than aluminum. On the other hand, application of a lower specific inductive capacity, Low-k, material to the intermediate insulation film between copper and silicon is also a crucial subject. From this viewpoint, the authors have been attempting to assess the stress change accompanied by heating and cooling on copper films deposited on a silicon substrate with three insulation layers having different capacity, and to clarify the influence of the insulation film material on the thermal stress. In the previous research, it was found that tensile stress was raised after a heat cycle. In present study, by means of X-ray diffraction, stress data previously measured from deflection amount has been confirmed, and then the effect of the heat cycle as well as the difference in the insulation film material on the grain size of the copper film has been investigation.

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Aluminum alloy sheets are attracting attention since they lighten an automobile body. Among them, some Al-Mg-Si alloys have already been applied practically to a part of automobile bodies because these alloys have hardenability during paint baking and do not cause a stretcher strain pattern. However, their bendability is significantly poor compared to that of steels. Therefore, in this paper, close microstructural observation has been made on the side surface as well as tension surface, in order to clarify the influence of the difference in composition of 9 kinds of Ai-Mg-Si alloys, i.e., amount of Mg_2Si, amount of excess Si, Cu addition, etc. Special care has been taken to the occurrence of the crack and unevenness. As a result, cracks were found to be prone to form when the amount of Mg_2Si or excess Si increased, although the increase in the amount of alloying element, particularly Cu, caused grain refinement.

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From the above result, a two-layers structure has improved the greatest problem of the low-toughness of MMC, from the field of structure.. The results obtained are summarized as follows : (1) The fatigue strength of a two-layers structure was the same as AC4CH material at the fatigue strength of Nf=1×(10)^7. (2) As a result of macroscopic observation, the destructive form of a twolayers structure had two different. (3) The origin part of a two-layers structure was the MMC section, and the final fracture was near the angle of aluminum alloys. (4) As a result of observing fracture of a two-layers structure in detail, fatigue fracture surface of face centered cubic lattice was seen from the border plane at the aluminum side. From this result, the fracture mechanism of a two-layers structure was what the fatigue crack initiation from MMC stops in a border plane, what a crack generates by face centered cubic lattice characteristic shearing strain of aluminum, carrying out ductile fracture and the last fractured. (5) From the above result, a two-layers structure type MMC has improved the consequence factor of the low-toughness of MMC. In addition, it is effective in making fatigue crack propagation stop, and has solved that it was material with high added values.

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In order to evaluate the fatigue reliability of the automobile components made from ADC12 to which plastic working was given, the fatigue crack progress characteristic of ADC12,which gave pre-distortion, was clarified. The result is as follows. (1) In II a stage of fatigue crack propagation, ΔK value of distortion material became smaller than non-distortion material. (2) In the design of a machine and a structure, it is important to take the influence of di stortion into consideration.

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To reduce tensile residual stress in a welded region, a new cooling method-which rapidly applies a water shower behind the welding-torch-was developed. In the case of applying this method to the welding of austenitic stainless-steel, the welding and cooling conditions are the parameters for reducing the residual stress efficiently. To optimize these conditions, first, the effects of the parameters on residual stress were determined by FEM. Second, the optimized conditions were determined by using the FEM results and a robust design technique. To confirm the accuracy of the optimized conditions, residual stresses under optimized or non-optimized conditions were experimentally measured. Under the non-optimized conditions, it was found that the residual stresses were tensile. On the other hand, under the optimized conditions, all residual stresses were compressive. These measurements results agree well with the FEM analytical ones; thus it can be concluded that the optimized conditions to reduce tensile residual are valid.

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Torsion processing has been investigated as methods which subject a commercial pure titanium square bar to severe plastic deformation without the adhesion to tools and any changes of shaping. Following the torsion to a suitable direction, the material is twisted in the opposite direction. This processing is continuously curried out by repetition, i.e. accumulative back-torsion (ABT) processing. Then the shape of the material is almost restored to the original. The ABT processing makes it possible to increase shearing strain to fracture more remarkably than the conventional torsion processing.

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This paper presents an analycal solution for an infinite strip having a symmetrically-located circular hole or a circular inclusion, where the strip is subjected to a bending moment at infinity. On the inclusion problem, two types of inclusions, i.e., perfect bonding and pure sliding are analyzed. The analysis is based on the Papkovich-Neuber stress function approach and the solution is obtained through a combination of harmonic functions of integral forms and infinite series. The boundary conditions at the interface of the strip and the inclusion are satisfied using the relations between the polar and Cartesian harmonics. The numerical results obtained from the proposed methods are illustrated the various stiffness ratios and sizes of the inclusion. The validity of the present solution is verified by comparing the theoretical results of Howland or Udoguchi.

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In this paper a crack identification method for plates is presented using both a genetic algorithm (GA) and FEM. In addition to an edge crack, this paper is concerned with an internal crack of plates. To identify the crack location and the width from frequency measurements, FEM program is also developed to calculate the natural frequencies of the cracked plates. The width and the position of the crack in the plate are estimated by using these natural frequencies and the GA. The availability of the proposed method is confirmed by results of numerical simulation.

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