-
Shotaro KODAMA
1985 Volume 51 Issue 464 Pages
961-966
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Etsuo TAKEUCHI, Saburo MATSUOKA, Satoshi NISHIJIMA, Megumi KIMURA
1985 Volume 51 Issue 464 Pages
967-974
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Koichi ASAKAWA, Seizo TAKAHASHI
1985 Volume 51 Issue 464 Pages
975-982
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Hideharu FUKUNAGA, Koichi GODA
1985 Volume 51 Issue 464 Pages
983-989
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Mitsunori MIKI, Kokichi FUJIMORI, Yasushi MIYANO
1985 Volume 51 Issue 464 Pages
990-998
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Kunio KOTANI, Minoru TANAKA
1985 Volume 51 Issue 464 Pages
999-1007
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Hironobu NISITANI, Masahiro ENDO
1985 Volume 51 Issue 464 Pages
1008-1016
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Hironobu NISITANI, Norio KAWAGOISHI, Minoru WAKAHARA
1985 Volume 51 Issue 464 Pages
1017-1025
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Hideo KITAGAWA, Yuji NAKASONE, Masuo SHIMODAIRA
1985 Volume 51 Issue 464 Pages
1026-1033
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Naotake NODA, Fumihiro ASHIDA
1985 Volume 51 Issue 464 Pages
1034-1041
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Yoshinobu TANIGAWA, Shouzo KURIYAMA, Yoitiro TAKEUTI
1985 Volume 51 Issue 464 Pages
1042-1049
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Yukitaka MURAKAMI, Makoto ISIDA
1985 Volume 51 Issue 464 Pages
1050-1056
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Masatoshi YATSUDA, Yukitaka MURAKAMI, Makoto ISIDA
1985 Volume 51 Issue 464 Pages
1057-1065
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Yotsugi SHIBUYA, Hideki SEKINE, Yoshio TAKAHASHI, Hiroyuki ABE
1985 Volume 51 Issue 464 Pages
1066-1072
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Hiromasa ISHIKAWA, Shigeru TADANO, Kin-ichi HATA
1985 Volume 51 Issue 464 Pages
1073-1081
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Toshio HIRANO, Koki MIZOGUCHI
1985 Volume 51 Issue 464 Pages
1082-1088
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Yasushi NIITSU, Kozo IKIGAMI
1985 Volume 51 Issue 464 Pages
1089-1097
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Manabu GOTOH, Kozo TANAKA
1985 Volume 51 Issue 464 Pages
1098-1106
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Mitsuyuki KOBAYASHI, Omi MIYAGAWA, Jinichiro TAKAHASHI
1985 Volume 51 Issue 464 Pages
1107-1114
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Masahiro ICHIKAWA, Tohru TAKAMATSU
1985 Volume 51 Issue 464 Pages
1115-1121
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Katsuhiko WATANABE, Hideyuki AZEGAMI
1985 Volume 51 Issue 464 Pages
1122-1130
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Toshio JINGU, Hiroyuki MATSUMOTO, Kikuo NEZU
1985 Volume 51 Issue 464 Pages
1131-1140
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Toshiyuki SAWA, Hisanori MARUYAMA, Hideki YANAGISAWA
1985 Volume 51 Issue 464 Pages
1141-1149
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Michio KURASHIGE
1985 Volume 51 Issue 464 Pages
1150-1152
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
-
Tashiyuki TORII, Kazuo HONDA
1985 Volume 51 Issue 464 Pages
1153-1160
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
An expression for evaluation of fatigue life was proposed on the basis of fatigue crack growth law, confirming the fact that tensile mean stress and tensile residual stress did not influence the fatigue crack initiation life but has effects of acceleration for the fatigue crack growth. By using this expression, bending S-N curves for base metals and laminated inhomogeneous plates were discussed. As a result, a constant m of fatigue crack growth law in which the growth rate was proportional to the mth power of stress level and a ratio of crack intiation life to fatigue life were estimated for surface microcracks of base metals subjected to bending fatigue. In addition, especially in laminated inhomogeneous plates, tensile mean stress was found to decrease fatigue life remarkably because fatigue crack growth comprised a significant portion of fatigue lifetime.
View full abstract
-
Yozo KATO, Motohisa HIROSE, Shinji SUZUKI
1985 Volume 51 Issue 464 Pages
1161-1167
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
It has been a serious problem whether the microstructure dependence of crack growth arises due to the change in crack closure level or intrinsic crack growth resistance. In order to investigate the effect of microstructure on fatigue crack growth behaviors at the threshold region, three kinds of ferrite base materials were fatigued at room temperature and slightly elevated temperatures. The fatigue results on the low carbon steel can be explained well by the ΔK
eff conception, that is, the crack growth resistance is not affected by the structural factors, such as cyclic strain aging and precipitation hardening by low temperature quench aging. On the other hand, the results on spheroidal graphite cast iron cannot be explained only by ΔK
eff conception. It may be considered that the graphite particles act as promoters at higher ΔK level and as obstacles at lower ΔK level to crack growth.
View full abstract
-
Kazuaki SHIOZAWA
1985 Volume 51 Issue 464 Pages
1168-1176
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
In order to study the interaction of fatigue cracks in structures subjected to cyclic loading, coupled compact tension specimens of JIS S45C, 0.45%C carbon steel, individually precracked to their initial lengths are loaded by common pins in the grip of fatigue machine. The crack propagation behaviour of coupled specimens fatigued under the stress ratio of 0.05 and 0.7 is compared with that of single specimen. The difference in crack propagation rate between specimens is explained with the mechanism of crack closure induced by residual tensile deformation which is left in the material behind the crack front and is a function of the crack lengths in individual specimens. The path of crack growth of coupled specimens is theoretically predicted and interaction law is discussed, based on the maximum released-strain-energy concept.
View full abstract
-
Yozo KATO, Norihiko HASEGAWA, Hirofumi MOCHIZUKI
1985 Volume 51 Issue 464 Pages
1177-1183
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
Quantitative observations have been made on the microcracks or small surface cracks in rotating bending fatigue tests of smooth specimens of a quenched and tempered Cr-Mo steel (SCM435) at temperatures up to 450°C. The total life reached a maximum value at about 350°C as a consequence of the inhibition of microcrack nucleation and the arrest of propagation due to cyclic strain aging. The length of microcrack nucleated was about 10μm. In the crack length range of about 300μm to 10mm, the da/dN-ΔK relations held up to 450°C. With the propagation stage from 10μm to 300μm, the relations of the linear fracture mechanics as the above mentioned were not always applicable. The most contribution of cyclic strain aging was performed in the propagation stage up to 300μm. The ratio of the number of cycles in this stage to the total life was about 85%.
View full abstract
-
Kohsoku NAGATA, Juichi FUKAKURA, Tadao MORI, Toshiyuki AIBA
1985 Volume 51 Issue 464 Pages
1184-1192
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
The fatigue strength of large and small-scale smooth specimens of a turbine-generator rotor steel was examined under torsional loading. Shear strain behaviour and axial crack growth of Mode II on smooth specimens and notched specimens were investigated in relation to size effect of the rotor steel. Elastic-plastic shear stress-strain characteristics at notch root were analyzied by finite element method. The main conclusions are as follows; (1) Size effect factor defined by the ratio of fatigue limits between 100 and 10 mm diameters was 0.78 and agreed the value of JSME recomendation (2) Shear stress-strain of notch root under large scale yielding condition can be estimated by expanded Neuber's rule, using inelastic nominal stress-strain relationship. (3) Using the modified parameter √(EJ
IIa), Mode II axial crack growth rate of smooth and notched specimens, in both elastic and plastic shear strain fields, was successfully expressed by linear regression lines.
View full abstract
-
Chitoshi MASUDA, Akira ISHII, Satoshi NISHIJIMA, Hideshi SUMIYOSHI, Yo ...
1985 Volume 51 Issue 464 Pages
1193-1199
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
Fatigue properties and fatigue fracture mechanisms were examined for three heats of SCr420 carburized steels. Carburizing, quenching and tempering were performed at four different conditions and fatigue strength was evaluated up to 10
8 cycles under ratationg bending at room temperature in laboratory air. The heat-to-heat variation of fatigue strength was about twice larger than the variation due to the difference of heat treatment, according to the diversity of the failure modes : failure from the specimen surface, fish-eye failure originated near the case-core interface, or fish-eye failure in the case, and different types of fish-eye origins as non-metallic inclusions, intergranular cracking, or stage I cracking. Fatigue life of the carburized steels would be predicted by the mode I crack propagation period originated from inclusions or intergranular cracking when these were the nuclei of the fish-eye ; the period for the formation of the stage I type cracks would have an important role when the fish-eye was started from this types of cracking.
View full abstract
-
Kohichi TANAKA, Yoshiharu MUTOH, Shuichi SAKODA
1985 Volume 51 Issue 464 Pages
1200-1207
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
Fretting fatigue strengths of high strength spring steel (JIS SUP9) were examined by clamping the contact pads of various materials ; the same steel, low strength carbon steel (SS41), plastics (POM) and ceramics (Si
3N
4). The fretting at a contact pressure of 60 MPa {6.1kgf/mm
2} reduced the fatigue strength by a factor of 1.92 for SUP9 contact pad and 1.68 for SS41 contact pad. The ceramics contact pads were similar to SUP9 steel contact pad, whereas the plastics contact pads did not cause the fretting. The friction coefficients between the contact pads and the specimen increased in proportion to the appropriate relative slip amplitudes, but attained to a saturation dependent on the contact materials. The saturation values were 0.6 for SUP9 steel, 0.34 for SS41 steel and 0.13 for POM. Cyclic J-integral concepts were successfully employed to predict crack propagation lives using measured data on the frictional forces.
View full abstract
-
Yozo KATO, Norihiko NAKANO
1985 Volume 51 Issue 464 Pages
1208-1214
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
Using the conditions of rotating bending and reversed torsion, these fatigue limits of smooth specimens were verified to be critical stress required to propagate the microcracks nucleated in the neighborhood of the graphites. The ratio of the critical stress in torsion to that in bending was about 80%. This value was nearly equal to that in a carbon steel with a micro-hole under the same loading conditions. At the stress level above the fatigue limit in bending, the ratios the number of cycles to microcrack nucleation and to microcrack coalescence to the total life were 3 to 7% and 78 to 89%, respectively. These ratios in torsion were 0.4 to 12% and 77 to 97%, respectively. While the ratios in bending were independent to the stress level, those in torsion were larger at the lower stress level.
View full abstract
-
Shoji HARADA, Yukitaka MURAKAMI, Yoshihiro FUKUSHIMA, Yutaka ISHIMATSU ...
1985 Volume 51 Issue 464 Pages
1215-1223
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
In order to investigate low-cycle fatigue life on the basis of serial observation of microcrack initiation and propagation, cyclic strain controlled-low-cycle fatigue tests were carried out on unnotched specimens. Either constant or two step strain amplitude was selected in experiments. It was found that the unnotched low-cycle fatigue process is dominated by the microcrack growth. The microcrack growth rate is proportional to a crack length. From those experimental evidence, the Manson-Coffin relation is derived using microcrack propagation law. Moreover, in case of two step strain cyclig, the prior fatigue history hardly gives effect on the subsequent microcrack growth. Combining such results as mentioned above, the Miner rule is found another indication of the microcrack propagation law.
View full abstract
-
Hideto SUZUKI, Masaru OUYABU, Tadashi UEKI, Takeshi KUNIO
1985 Volume 51 Issue 464 Pages
1224-1229
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
The rotating fatigue tests were carried out on nodular irons with 7 types of matrix structures prepared by heat treatments, and effects of matrix structure on the fatigue limit σ
w were examined. In order to study the crack initiation and growth, the fracture surface was observed by SEM. The results obtained were as follows : (1) The effect of matrix structure on σ
w was remarkable. (2) Among irons with ferrite-pearlite duplex structures, the iron with the finest spheroidal graphite prepared by the metal mold had the highest fatigue limit. (3) Among irons with hardened matrix structure prepared by cooling of high rate, the iron with upper bainite had the highest fatigue limit. (4) The matrix structure influenced the metallurgical factor that initiated the crack, because increasing H
v of the matrix structure induced the high notch sensivity of micro-porosity. This fact caused the effect of matrix structure on σ
w.
View full abstract
-
Hideo KITAGAWA, Yuuji NAKASONE, Tsuyoshi SHIMAZAKI, Eiichi HIGASHIDE, ...
1985 Volume 51 Issue 464 Pages
1230-1234
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
It has been said that σ phase degrades materials ; nevertheless, it is not clear how σ phase degrades materials. In order to clarify the meaning of σ phase degradation in a strength-of-materials sence, this paper evaluates the tensile, impact and fatigue properties of a cast stainless steel which contains approximately 10 wt% of σ phase. The results obtained are as follows : (1) The Charpy absorbed energy of the σ-phase-degraded stainless steel was greatly reduced even at room temperature. (2) The tensile properties of the steel such as 0.2% proof stess, tensile stress and elongation were not affected by σ phase. (3) The S-N diagram was not changed by the existence of σ phase in steel. The distribution of the maximum surface lengths of multiple small cracks in the degraded steel, however, was different from that in non-degraded steel.
View full abstract
-
Toshimi KONDO, Hideki SEKINE, Osamu TAMATE
1985 Volume 51 Issue 464 Pages
1235-1241
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
This paper is concerned with the periodic cracks in the neighborhood of the interface of two anisotropic bodies under longitudinal shear. The analysis is based on the singular point method. Replacing the cracks with continuous distributions of screw dislocations, we obtain a singular integral equation with Cauchy kernel. Numerical results for the stress intensity factors are plotted in terms of the geometrical parameters of crack arrangement and physical properties of the anisotropic bodies.
View full abstract
-
Michiya KISHIDA, Kazuaki SASAKI, Shiroh NISHIZAWA
1985 Volume 51 Issue 464 Pages
1242-1248
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
In the linear couple-stress theory, three-dimensional elastic stress analysis of a plate is carried out, in order to evaluate the thin-plate theory. The problem treated here is the axisymmetric bending of a clamped circular plate subjected to an annularly distributed load. For this analysis, the use is made of the indirect fictitious-boundary integral method. From the results, the applicability of the thin-plate theory is investigated, and further, the effects of various parameters, such as the characteristic length and the bending-twisting modulus, on the behaviour of a plate are made clear.
View full abstract
-
Yoshihiro TOMIYA, Akio SHINDO
1985 Volume 51 Issue 464 Pages
1249-1255
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
The paper has dealt with the investigation into the effect of material characteristics upon the bifurcation limit of square elastic-plastic orthotropic plates subjected to tension in their diagonal line in terms of bifurcation analysis. The results clarified that there were beneficial material characteristics upon improving the bifurcation limit and revealed the importance of inclusion of orthotropic effect upon the bifurcation limit. Although the investigation has been restricted to bifurcation limit, the important correlation between the bifurcation limit and the height of the wrinkle observed by experiment has been verified. The method can be applicable to the more thorough understanding of material aspect of bifurcation behaviour from the theoretical point of view.
View full abstract
-
Yoshio MIYOSHI, Keiji OGURA, Yasuyuki MIWA
1985 Volume 51 Issue 464 Pages
1256-1262
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
Crack growth behaviors of a type 301 and a type 304 austenitic stainless steel under cathodic charging were examined. Hydrogen assisted accelerated crack growth was observed both under cyclic loading and sustained constant loading. Time dependent slow crack growth was observed above a threshold stress intensity factor of K
IHE. The value of K
IHE was found to be lowered by a superimposed cyclic load. This was considered to be due to the formation of the plasticity induced martensite and a cyclic sharpening effect at an advancing crack tip in this study. The time dependent crack growth was more pronounced by a sensitizing treatment in the type of 304 steel. Fracture surfaces corresponding to the time dependent crack growth were primarily quasi-cleavage fasets and were found to be associated with the hydrogen embrittlement.
View full abstract
-
Kiyotsugu OHJI, Shiro KUBO, Masahiro TSUJI, Shigeo MIYAMOTO
1985 Volume 51 Issue 464 Pages
1263-1270
Published: April 25, 1985
Released on J-STAGE: February 21, 2008
JOURNAL
FREE ACCESS
For a two-dimensional body with a crack, J integral is described as a function of stress intensity factor, while M integral is expressed in terms of stress intensity factor and crack length. By combining these characteristics with the path-independence of these two integrals, a method was proposed of evaluating crack length and stress intensity factor simultaneously from strain-gage measurements along a given integral path. Engineering applicability of the proposed method was examined by experiments and FEM simulation analysis with a center-cracked panel and a double-edge-cracked panel. Good accuracy was obtained for the stress intensity factor determined form J integral, irrespective of crack length. The crack length evaluation was also satisfactory for long cracks, but relatively poor for short cracks; this resulted form the accuracy of M integral evaluation. Gauss quadrature was found useful for reducing number of measuring points of strain without sacrificing the accuracies of the two quantities.
View full abstract
