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- TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C
- TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B
- TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A
- Transactions of the Japan Society of Mechanical Engineers Series C
- Transactions of the Japan Society of Mechanical Engineers Series B
Volume 53, Issue 489
Displaying 1-23 of 23 articles from this issue
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Susumu TAKAHASHI1987 Volume 53 Issue 489 Pages 861-862
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSDownload PDF (376K) -
Tsuneshichi TANAKA, Tatsuo SAKAI, Kenji OKADA, Nobushige TAMURA1987 Volume 53 Issue 489 Pages 863-870
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSIt is well known that the fatigue failure of metallic materials will occur due to the initiation of cracks and their subsequent growth. However, the number of crack nuclei is not provided deterministically and the number is not so small in many cases of engineering application. In these cases, the number of initiated cracks is also randomly variable and this should be taken into account in the evaluation of crack coalescence. In the present study, based on the numbers of initiated cracks, a statistical evaluation was made of the coalescence of cracks as a function of the number of stress cycles, and the fatigue life distribution was probabilistically derived from the above evaluation assuming that failure occurs immediately after the coalescence of cracks. The analytical results obtained are in good agreement with the experimental results of fatigue life distribution.View full abstractDownload PDF (983K) -
Yukitaka MURAKAMI, Kenji MATSUDA1987 Volume 53 Issue 489 Pages 871-877
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe value of ΔKeff, th for a medium carbon steel (0.46%C) was measured by a rotating bending fatigue test using specimens which were annealed after introducing fatigue cracks. Since the fatigue cracks become ideal cracks after annealing, ΔKeff, , th can be determined by finding the critical stress under which no crack growth occurs. The values of Kop/Kmax for a stationary fatigue crack in the rotating bending fatigue test(R=-1) were estimated by the Dugdale model as Kop/Kmax=-1.0 over a wide range of stresses. The values of ΔKeff, th obtained in this study were 3.4∼3.6 MPa·m1/2 and were approximately independent of crack size in the range from 100 μm to 1 000 μm. The importance of this value for short cracks is emphasized from the view point of fatigue under varying loads which include both high and low stress amplitudes.View full abstractDownload PDF (869K) -
Michiya KISHIDA, Kazuaki SASAKI, Yukio ISHIDA, Akihiko NOGUCHI1987 Volume 53 Issue 489 Pages 878-883
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe elastic stress analysis of a three-dimensional crack is carried out by the use of the indirect boundary integral method. The fundamental solutions of this method are simple- and double-layer potentials. This method has the advantages that discontinuity of a layer potential on the crack surface is related to that of displacement, i. e. crack opening displacement. As a result, the stress intensity factors and the crack opening displacement of penny and ring shaped cracks are obtained and the usefulness of this method in crack problems is shown by comparison with other results.View full abstractDownload PDF (706K) -
Yoshio MIKITA, Ichiro NAKABAYASHI1987 Volume 53 Issue 489 Pages 884-889
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSOuench cracking is generally considered to occur under thermal and transformational stresses. In this paper, some of the quench effects on cracks (fin and/or vertical), hardness and residual stresses of a SUJ 2 bar were examined by using polyalkylene glycol (PAG) solutions. The fin crack by water quenching occurred in all specimens at the austenitizing temperatures higher than 800°C. Similarly, the vertical crack occurred in all specimens at higher than 900°C. The increase in PAG polymer concentration results in the decrease of a fin crack and increase of a vertical crack. The PAG quenchant temperature is closely related to the fin crack, because of the clouding points of PAG solutions. The residual stresses caused by quenching were mearured by the X-ray diffraction method. A considerable tensile stress existed on the surface area of all specimens.View full abstractDownload PDF (796K) -
Kiyohiko IKEDA, Hisashi IGAKI1987 Volume 53 Issue 489 Pages 890-893
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSIn order to examine the effect of subcritical crack growth on fracture strength under multiaxial stress by considering subcritical crack growth, soda-lime glass specimens having a controlled surface flaw introduced by Knoop microhardness indentation were fractured by four-point bending under different hydrostatic pressures up to 100 MPa and different stressing rate conditions. For both as-indented specimens and specimens without residual stresses, it was found that the fracture stress evidently increased under hydrostatic pressure of 100 MPa and a high stressing rate condition, as subcritical crack growth was fully restricted under those conditions.View full abstractDownload PDF (624K) -
Hiroyuki MURATA, Toshiyuki HASHIDA, Tetsuo SHOJI, Hideaki TAKAHASHI1987 Volume 53 Issue 489 Pages 894-898
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThis paper describes an experimental investigation of the effect anisotropy on mixed mode crack propagation in granite by the use of asymmetric three-point bend specimens. Acoustic emission techniques were employed during the fracture tests to detect the onset of kinked crack extension. In order to characterize the fracture strength anisotropy, uniaxial tension tests and Brazilian tests were conducted, and fracture strength was measured as a function of direction with respect to the anisotropy. Based on the fracture strength data, the results of the mixed mode fracture tests were analyzed with regard to the fracture angle by means of linear elastic fracture mechanics. It is shown that the concept of a critical tensile stress at a characteristic distance, modified to account for the anisotropy of fracture strength, can explain the observed extension behaviors mixed mode cracks.View full abstractDownload PDF (674K) -
Kikuo KISHIMOTO, Arata SUZUKI, Shigeru AOKI, Masaru SAKATA1987 Volume 53 Issue 489 Pages 899-904
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe time variation of fracture mechanics parameters may be computed by the finite element method. However, this method requires a large computer time and is not conveniently used in material testing. In a previous paper, the authors derived a simple formula for calculating the dynamic stress intensity factor of an elastic three-point bend specimen subjected to impact loading. In the present paper, the formula is extended to include large scale yielding by introducing a plastic zone correction, and a simple method is proposed for evaluating the J^^-integral, a dynamic fracture mechanics parameter which is an extension of the J-integral and includes the effects of inertia force etc. Numerical examples are presented to demonstrate the practical applicability of the method. It is shown that a reasonable accuracy is obtained by the present method as compared with the elastic/viscoplastic finite element computation; and the CPU-time is within 1% of the finite element method. The limitation of the present method is also discussed.View full abstractDownload PDF (722K) -
Kenji SEO, Jun-ichi MASAKI, Fumio NOGATA, Masahiro KUSAKA1987 Volume 53 Issue 489 Pages 905-910
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThis study was carried out to characterize the behaviour of brittle fracture initiation at the ductile-to-brittle transition region temperature. In the experiment, V-notch Charpy specimens, which had a local mechanical heterogeneity at the vicinity of the notch root, were used for evaluating the brittle fracture resistance of steel. The absorbed energy of the specimen with mechanical heterogeneity in the Charpy impact test was not a proper measure due to the existence of local mechanical heterogeneity. The elasto-plastic analysis on stress and strain in Charpy specimens with mechanical heterogeneity were conducted by using the finite element method. The energy release rate for crack propagation in Charpy specimens with mechanical heterogeneity was calculated. It was shown that the energy release rate could be employed as the criterion for ductile-to-brittle transition in the Charpy test.View full abstractDownload PDF (905K) -
Senji IMAMURA, Yasuo SATO1987 Volume 53 Issue 489 Pages 911-915
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThis paper describes the experimental results and the theoretical analysis concerning the size effect on yielding of a solid cylinder of a mild steel with a transverse hole subjected to compression. We made the theoretical analysis by taking the effect of the surface layer into account. The analytical results coincide well with the experimental data and concluded as follows : (1) There are two modes in yielding ; one is the yielding taking place in the whole section and the other is that taking place locally. (2) The yield point of the cylinder is influenced not only by the ratio of the diameter between the hole and the test cylinder, but also by the diameter of the cylinder. Moreover, we point out that the thickness of the surface layer is 0.16mm which corresponds to about 5∼6 times the grain size of the material.View full abstractDownload PDF (680K) -
Masaaki YOKOYAMA, Shigeru SASAKI1987 Volume 53 Issue 489 Pages 916-925
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSAs a basic study for the establishment of an accuracy estimation method in structural analysis using the zooming method, this report deals with the finite element analysis of the problems of transverse bending of thin, flat plates. From numerical experiments for uniform mesh divisions, the following relation was deduced, ε∝(h/a)k, k≥-1, where ε is the error of the value by the finite element method relative to exact value and h/a is the dimensionless mesh diameter. Using this relation, the errors of gradients on a zooming boundary and that of the bending moment at the selected points in the zooming region can be estimated by the recursive analyses of the whole region or of the zooming region. The error of the bending moment at the selected points is expected to be smaller than the sum of these two errors. A computer program using this error estimation method was developed and applied to sixteen problems of various shapes. The usefulness of this accuracy estimation method was illustrated by these application results.View full abstractDownload PDF (1227K) -
Yeonseung KIM, Hitoshi NAGAO1987 Volume 53 Issue 489 Pages 926-929
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSNowadays, due to the development of the sandwich core series and the progression of the degree of exactness required for each thickness of sandwich plate, optimum design of the structural sandwich plate is needed. We can find several papers for optimum design of laminated plates. They deal with optimum density or optimum fiber direction of each ply, and optimum orthotropic layers under uniaxial and biaxial compression. But we can find no paper for the optimum design of a sandwich plate with a hole or notch witch produces stress concentration. Thus, this paper presents one optimum design method for a sandwich plate with a hole or notch, which searches least weight or least cost per bending strength.View full abstractDownload PDF (509K) -
Hideki SEKINE, Shoji KAMIYA1987 Volume 53 Issue 489 Pages 930-934
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSA semi-infinite shear fracture initiated from notch roots or other stress concentrators in undidrectional fiber-reinforced composites is considered on the basis of the two-dimensional theory of orthotropic elasticity. In a previous paper we have dealt with the stress intensity factors at the tip of a semi-infinite shear fracture in an infinite strip with stress-free-boundaries under tensile loading. As a result we have pointer out that the well-known method of energy balance is inappropriate for estimating stress intensity factors. The present paper continues from the previous paper and deals with the stress intensity factors for the case where the displacement on boundaries is constrained in the direction normal to the shear fracture. In contrast to the result of the previous paper, the energy balance method gives a good approximation to the stress intensity factors for both the opening and in-plane-shear modes.View full abstractDownload PDF (595K) -
Xiaolie CHEN, Keijiro NAKASA1987 Volume 53 Issue 489 Pages 935-940
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThree-point and four-point bending tests were carried out in water on the high strength Ni-Cr-Mo steel quenched and tempered at 653 K in order to investigate the effect mixed mode I-II loading on tte crack propagation and crack branching in delayed failure. The crack propagation velocity before crack branching was almost independent of the ratio of mode II to mode I stress intensity factor when it was within 0.3. Both the crack branching angle and the deviation of crack branching angle to the crack propagation direction before crack branching increased with increase in the ratio of mode II to mode I stress intensity factor. The above results were explained by an criterion which was introduced by combining the hydrostatic tensile stress and the hydrogen concentration at a crack tip.View full abstractDownload PDF (706K) -
Yoshihiro SUGANO1987 Volume 53 Issue 489 Pages 941-946
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSA plane thermoelastic problem in a nonhomogeneous doubly-connected region under a transient temperature field has been formulated by the stress function method. In the formulation, new Michell's conditions have been derived to assure a single-valuedness of the rotating and displacements in the nonhomogeneous doubly-connected region. The system of fundamental equations formulated has been solved numerically by the use of the finite difference method. To make clear quantitatively the effects of thermal and mechanical nonhomogeneous properties on temperature and thermal stress distributions, numerical calculations are carried out for the thermal conductivity, Young's modulus and coefficient of linear thermal expansion which vary exponentially with the position in the doubly-connected region.View full abstractDownload PDF (743K) -
Terumi YAMAMOTO, Tosiyuki NAKAGIRI, Tosimitu TUMURA1987 Volume 53 Issue 489 Pages 947-953
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThis paper is concerned with the mixed boundary value problems of an infinite plate with an elliptic hole. Into which a smooth rigid elliptic plug is simply inserted. Since the infinite plate is subjected to a uniaxial loading (tension or compression) at infinity, apertures are produced in parts along the boundary between the inserted plug and hole. The contact pressure between the inserted plug and the hole is expressed in a convergent series whose differential from is also convergent, so that the stress and displacement generated along the boundary can be numerically analyzed by the point matching method. Using the numerical results for various elliptic shapes, the influence of interference is shown with the stress around an elliptic hole.View full abstractDownload PDF (746K) -
Masashi DAIMARUYA, Masachika NAITOH1987 Volume 53 Issue 489 Pages 954-958
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe aim of this paper is to illustrate the effect of thermoelastic coupling on the propagation of Rayleigh-Lamb waves in an infinite plate. The propagation of thermoelastic waves in a plate bounded by fraction-free surfaces is studied on the basis of the linear theory of coupled thermoelasticity taking into account the coupling between the strain and temperature fields. The characteristic equations are derived for the thermal condition of general heat transfer on the surfaces and their asymptotic equations for particular cases are also examined. Especially, numerical evaluations corresponding to the first three modes of symmetric and antisymmetric waves are carried out over wide range of frequencies, and the thermoelastic energy dissipation together with the phase velocity for both adiabatic and isothermal boundary conditions are illustrated and discussed in detail.View full abstractDownload PDF (625K) -
Chuji KAGAYA1987 Volume 53 Issue 489 Pages 959-963
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe purpose of this paper is to investigate the effectiveness of an inorganic coating to prevent embrittlement. Charpy impact tests were carried out, using specimens of S48C and SCM435 steel partially protected from tufftriding by the coating. The main results obtained are as follows : (1) The formations of nitriding layers were restrained by the inorganic coating regardless of the steel used. The impact value of the anti-tufftrided steel, which was treated for 120 minutes was the same as the impact value of tufftrided steel which was treated for 30minutes. (2) The transition temperature rise of the anti-tufftrided steel was considerably restrained in both type of steels when compared with the tufftrided steel. However this restraint can be attributed to alloy elements of the material and was more marked in the SCM435 steel containing Chromium. (3) This coating can be applied effectively to partially prevent embrittlement or decrease in impact value as an insulating agent of tufftriding.View full abstractDownload PDF (682K) -
Chuji KAGAYA, Noboru EGAMI1987 Volume 53 Issue 489 Pages 964-969
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe effectiveness of an inorganic coating to ensure the weldability of tufftrided steel is investigated by Co2 are welding, friction welding and tension test, using specimens of SM50A and S15CK steel partially protected from tufftriding by the coating. The results obtained are summarized as follows : (1) In the CO2 are welded joint, the tensile strength of the tufftrided steel after 90minutes was remarkably reduced due to porosity and lack of penetration. But the anti-tufftrided steel was as strong as the non-tufftrided steel regardless of tufftriding time. (2) The porosity of the tufftrided steel was influenced to a greater extent by the compound layer than by the diffusion layer. (3) Friction welding of the anti-tufftrided steel was fully possible under the same condition as was welding with non-tufftrided steel. However, in case of long time tufftrided steel it was difficult to establish welding conditions and ensure strength.View full abstractDownload PDF (773K) -
Masashi DAIMARUYA, Masachika NAITOH, Shinji TANIMURA, Kasuyuki SASAKI1987 Volume 53 Issue 489 Pages 970-974
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe present paper is concerned with the duration of contact at plastic impact of a finite-length bar on a rigid body. The duration of impact is predicted on the basis of the strain-rate dependent theory of plastic wave propagation. Thus the variations of elastic-plastic stress at the impact end of lead bars are examined by using the constitutive equation obtained from the split Hopkinson bar. Next, a new method for measuring the duration of impact is proposed which is termed the sensing cylinder. This method is effective for measuring not only the duration of impact but also the impulsive force at the impact end. The experimental verifications of the duration of impact are made for lead bars of four different lengths. The time variations of stress at the impact end of the bars colliding with the sensing cylinder under various impact velocities are measured. The theoretical predictions are in good agreement with experimental observations.View full abstractDownload PDF (671K) -
Masashi DAIMARUYA, Masachika NAITOH, Shinji TANIMURA, Masashi CHIBA1987 Volume 53 Issue 489 Pages 975-979
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSThe present paper deals with the dynamic behavior of an elastic-plastic bar of finite length colliding longitudinally with a rigid wall. The dynamic, plastic deformation of a finite length bar and the appearance conditions of a plastic strain plateau adjacent to the impacted end are examined on the basis of the strain-rate dependence theory for plastic wave propagation. It is shown that the asymptotic formation of a strain plateau in a finite length bar is governed by the magnitude of strain-rate sensitivity, the impact velocity and the length of the bar. In addition, the distribution of plastic strain along finite length bars is found to gradually approach a certain profile with increasing length of the bars. The experimental results on annealed pure aluminum bars of various lengths have shown to agree well with the theoretical predictions.View full abstractDownload PDF (661K) -
Nobuyuki KANEKO, Toshio NAKAYAMA, Nobuo INOUE1987 Volume 53 Issue 489 Pages 980-985
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSPolymers can be considered isotropic when they have not been cold worked, but they become highly anisotropic when plastically deformed. Biaxially drawn high density polyethylene (HDPE) sheets were prepared by forging them between a pair of opposing punches. Various rates of biaxial drawing were achieved by changing the aspect ratios of the rectangular specimens. In the previous paper, they were subsequentry subjected to tension tests in the direction of principal strain, and the coefficients of anisotropic yield condition were determined for various amounts of principal strains. In the present paper, on the other hand, the test directions were angled 22.5°, 45°, and 67.5° to the principal strain direction. One of the anisotropic coefficients left unknown in the previous study was thus obtained.View full abstractDownload PDF (638K) -
Nobuyuki KANEKO, Toshio NAKAYAMA, Nobuo INOUE1987 Volume 53 Issue 489 Pages 986-991
Published: May 25, 1987
Released on J-STAGE: February 21, 2008
JOURNAL FREE ACCESSPolymers are isotropic when they have not been cold worked, but they become highly anisotropic when plastically deformed. Biaxially drawn high density polyethylene (HDPE) sheets were prepared by forging them in compression between a pair of opposing punches. Various degrees and types of biaxial drawings were achieved by changing the aspect ratios of the rectangular specimens. They were subsequenty subjected to tension tests in the direction of compression. The yield strength remaining assumed in the previous study was thus determined. The energy method was applied to the backward extrusion and tube previous extrusion-expansion of HDPE with various extrusion ratios at room temperature. A good agreement was obtained between the theory and the experiments. It is concluded that anisotropy should be taken into consideration when applying the energy method to polymer forming.View full abstractDownload PDF (663K)
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