材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
18 巻 , 191 号
選択された号の論文の14件中1~14を表示しています
  • 西岡 邦夫, 平川 賢爾
    1969 年 18 巻 191 号 p. 669-678
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
  • X線材料強度部門委員会第2分科会
    1969 年 18 巻 191 号 p. 679-684
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    X-ray studies on fatigue have recently been made to considerable extent, and it has been found that the X-ray parameters, such as the broadening and peak-shift of diffraction line, represent very well the state of fatigued metals. Under these circumstances, the 2nd Division of the Committee for the X-ray Study on Deformation and Fracture of Solid Material in the Society of Material Scinece, Japan, have conducted a series of studies by collaboration of scientists with a view to intending further development in this field of studies.
    This is the first report of this Division as a survey of the investigation conducted. The part included in this volume is mainly concerned with the characteristic feartures of fatigue phenomena from the point of view of X-ray diffraction.
  • X線材料強度部門委員会第2分科会
    1969 年 18 巻 191 号 p. 685-688
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    In the previous part of this report, it was mentioned that X-ray parameters are significant factors in the study of fatigue. Some studies conducted on metals of much practical cases form this part of report. The X-ray phenomena in these cases are not always the same as what was mentioned in the previous part, but they present the characteristics of fatigue.
    The purpose of activities in this Division is explained by pointing out how and what kind of fatigue problems are going to be treated.
  • 山田 敏郎, 北川 茂
    1969 年 18 巻 191 号 p. 689-694
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    Two kinds of fatigue tests were conducted, where two sinusoidal loadings were superimposed on each other, and where rectangular cyclic loadings were superimposed with sinusoidal loadings. The materials used were aluminum alloys, 17ST4 and 7075-T6. Those fracture surfaces were observed by means of an optical microscope and an electron microscope. Those observed patterns indicated the following striations; under constant amplitude loading cycles, the striations had even spaces within the glance area; under fluctuating load cycles, they had varied contrast and spaces, and presented clear periodicities corresponding to the load fluctuations. For example, in the case where 8 sinusoidal loadings were superimposed on each other in a rectangular wave cycle, 4 striations corresponding to σamr were distinct, but 4 other striations corresponding to σamr were feeble, where σa stood for the amplitude of sinusoidal stress cycle and σmr for the rectangular stress cycle. In consequence of those observations, it was clarified that the striations stood to the loading cycles as one to one, and that the maximum value of those striations and loadings stood each to each equally.
  • 吉田 彰, 田中 政夫, 津和 秀夫
    1969 年 18 巻 191 号 p. 695-701
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    The materials used in machine parts, especially, steels suffer almost always from machining. The effect of this machining on the mechanical properties of materials presents a serious problem, of which reinquiry is urgently required on account of the higher efficiency of machine parts that has been attaind in recent years. Therefore, in this paper the fatigue strength of the turned and the surface-rolled low carbon steels under the various machining conditions was examined, in order to clarify the relation between the fatigue strength and machining conditions, systematically. These results are discussed considering the work hardened surface layer. The main results are as follows:
    (1) The fatigue strength of the machined specimens increased by 10 to 20% for turning, and by 30 to 130% for surface-rolling, respectively, as compared with that of the annealed specimen.
    (2) The relation between the fatigue limit and the work hardened surface layer could be represented in the following equation.
    σ*0[1+K{H(I.V.)}1/n/100], H(I.V.)=∫li0{H(l)-H0}dl
    where, σ* is the fatigue limit of the machined specimen including only the effect of the work hardened surface layer, σ0 is the fatigue limit of the annealed specimen, H(I.V.) is the integrated value of hardness increasing by work hardening, H(l) is Vickers hardness at the depth l from the surface of machined specimen, H0 is Vickers hardness of the annealed specimen, li is the depth of the work hardened surface layer, and K and n are constants depending upon the material, the machining method and the stress concentration factor of the specimen.
  • 椹木 義一, 明石 一, 寺石 稔, 藤井 太一
    1969 年 18 巻 191 号 p. 702-706
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    It is well known that almost all the b. c. c. metals show brittleness at low temperature. This property means that viscosity falls with decrease in temperature. It is expected from this that there is a change of ultrasonic attenuation in the metal at the transition region from ductile to brittle property. In our previous investigation, attenuation in carbon steels at low temperature decreased suddenly in a way similar to the notched-bar impact value under similar condition.
    In the present paper is reported the change of transition temperature of the ultrasonic attenuation in S20C carbon steel with the number of repeated stress cycles within the range of -20°C to room temperature. The relation is explained by Orowan's theory.
    The results are summarized as follows:
    (1) The transition temperature rises with increase in the number of repeated stress cycles, and the rising rate depends on the amplitude of repeated stress.
    (2) The transition region becomes small with increase in the number of repeated stress cycles.
    (3) The model which had been conceived previously for the relation between attenuation and fatigue of carbon steel, has been adapted to the fatigued S20C carbon steel at the region from ductile to brittle property.
  • 中沢 一, 川田 雄一
    1969 年 18 巻 191 号 p. 707-713
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    A series of fatigue tests of steel were carried out, by alternating plane bending, twisting and rotating-bending, with the cast steel specimens which had been cut off from a cast-steel roll with a diameter of 1200mm. The results are discussed from a standpoint of an analysis of the effects of material-defects. The findings are as follows.
    (1) The ratio of fatigue limit of alternating twisting and rotating-bending equals to 3/4. It is explained by the stress-concentration around a small blow-hole.
    (2) The fatigue life is affected by the rate of material defects. The general S-N curve expresses the fatigue life of the specimens whose rate of defects equals in value to the mean value of the specimens used in the experiment. It is shown also that as far as the rate of defects becomes smaller in value, so far the fatigue life becomes longer.
  • 田中 政夫, 福永 秀春
    1969 年 18 巻 191 号 p. 714-720
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    It is considered that the fatigue behaviour in the liquid metal environment depends upon the simultaneous effect of the chemical actions such as dissolution of solid metal into molten metal, diffusion of molten metal into solid metal and embrittling tendency of liquid metal. In this contect, several factors such as the tensile properties of a notched specimen, dissolution rate, hardness distribution and residual stress in the surface layer of the low carbon steel which had been immersed in molten tin and lead, mode of non-propagating crack and path of fatigue crack and deformed layer at crack side through a X-ray micro-beam. Analysis, from which the following experimental facts have been made clear;
    (1) The increase in the fatigue strength of low carbon steel in molten tin is mainly caused by the increasing compressive stress originating by the diffusion of tin in steel and by the dissolution of the crack tip of steel in the molten tin.
    (2) The fatigue crack in molten metal propagates itself along the grain boundary while the fatigue crack in air crosses over the grain.
    (3) The mean crack growth rate under the same stress level depends upon the environment. The crystal distorsion at crack side becomes larger as the mean crack growth rate decreases.
    (4) The fatigue strength in high stress level is made extensively to decrease by liquid metal embrittlement.
    (5) The chemical action between the molten metal and the solid metal will control the behaviour of the lower stress with a larger number of cycle fatigue, and the embrittlement effect by the liquid metal is dominant over the higher stress with a smaller number of cycle fatigue.
    (6) By developing the above-mentioned results, the system of S-N curves of the solid metal in a liquid metal environment is schematically proposed.
  • 平 修二, 田中 啓介
    1969 年 18 巻 191 号 p. 721-726
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    The true tensile stress and the natural strain are found to be correlated with the excess dislocation density obtained from X-ray microbeam observation and with micro Vickers hardness value, as has been reported in the preceding paper. In the present study, the excess dislocation density of fatigued specimens, was measured and used to estimate the flow stress and the strain at specific localized region in these specimens, such as crack tips. The stress concentration factor at the crack tip was evaluated successfully.
    The method to estimate the flow stress and the strain from the excess dislocation density or from micro Vickers hardness value was also applied to the estimation of these quantities in various kinds of specimens, including the tensile specimens fractured at low temperature, the Charpy impact specimens fractured at several temperature levels below room temperature, the creep specimens deformed at 450°C or ruptured at 500°C and the cold-rolled specimens. And the applicability of this method was discussed in each case.
  • 徳岡 辰雄, 斎藤 正克
    1969 年 18 巻 191 号 p. 727-730
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    The ultrasonic wave propagations in a deformed crystal with symmetry in whatever respect have been theoretically investigated by a method similar to that of Thurston2). A weak ultrasonic wave deformation has been superposed on a statically deformed state of the crystal. Substituting the general anisotropic linear stress-strain relation (4) and the assumed plane wave solution (16) into the equation of motion (15), the rotationless propagation condition (20) proposed by Truesdell7) is specified by the statically deformed state for a given propagation direction, and the propagation velocities are determined by the eigenvalues of the acoustical tensor (19). The static deformation is so small that the second and higher order of the displacement gradient are to be neglected, and the effect of the applied stress is regarded as perturbation. The acoustical tensor is then explicitly expressed by the stress in the first-order approximation (23). The characteristic equation (28) obtained from the propagation condition (20) is reduced to the relation (31) which gives the perturbations of the eigenvalues of the acoustical tensor (33) and (34). This method is restricted to the non-degenerate case with respect to the propagation velocities of the natural state. The velocity difference of two quasitransverse waves is calculated, which indicates the acoustical birefringence and consists of the intrinsic anisotropy of a crystal and the effect of the applied stress. The formulae thus obtained are applied to the orthorhombic system, and the results show that the acoustical birefringence for the waves propagating along a crystal axis depends on the three normal stresses along the crystal axes.
  • 野口 達彦
    1969 年 18 巻 191 号 p. 731-737
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    In view of the fact that the specific surface area of phosphate rock and its crystallite size are important factors that impart such physical properties as will affect its chemical reactivity with sulfuric acid to produce calcium superphosphate, its specific surface area and crystallite size were respectively measured. The specific surface area of various phosphate rocks which are found deposited throughout the world was determined by the method of liquid adsorption with stearic acid in benzene solution, and the method of gas adsorption with ethylether, respectively.
    The results were as follows.
    The specific surface area measured by gas adsorption showed larger value than that by the method of liquid adsorption, but both the values showed the same tendency. The specific surface area measured by the method of liquid adsorption ranged from 3 to 8m2/g and that by the method of gas adsorption ranged from 8 to 20m2/g. The specific surface area of Gf (Gafsa), Ko (Kosseir) etc. were larger than those of F (Florida), Ma (Makatea) etc.
    The difference between these specific surface area values is attributed to a lesspenetration of stearic acid into the internal surface of phosphate rocks. In general, the specific surface area of phosphate rock increases with increasing the content of carbonate in the phosphate rock.
    Determination of the crystallite size was made from half value breadth of the X-ray diffraction pattern. The crystallite sizes of F68 and F66 rocks were larger than those of Gf, Ko, and An rocks, etc. Carbonation seems to reduce the crystallite size of the phosphate rock and thereby increase the specific surface area of the phosphate rock.
    The reactivity of phosphate rock with sulfuric acid was deduced by measuring CaO/P2O5 ratio and carbonate content, the specific surface area by the convenient method of adsorption of stearic acid, and crystallite size etc.
  • 岡 行俊, 木山 英郎, 平松 良雄
    1969 年 18 巻 191 号 p. 738-744
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    Recently the authors proposed a method of testing tensile strength of rocks with irregular test pieces subjected to a pair of concentrated loads.
    It is the object of the present investigation to examine whether or not a similar method can be applied to the test of concrete. From the theoretical analysis and experiments, it has been found that the tensile strength of concrete can be determined by compressing cylindrical test pieces axially over limited areas if it is conducted under suitable condition. It is found also that deviations of the test results are negligible. The suitable conditions are described in detail in the paper.
  • 功刀 雅長, 大田 陸夫, 藤本 勝司, 小川 智司, 宮田 昇
    1969 年 18 巻 191 号 p. 745-751
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
    The spectrophotometric and magnetic properties of alkali phosphate glasses containing cobalt have been determined and interpreted in terms of the ligand field theory.
    The coloured glasses showed a relationship between their mass magnetic susceptibilities χg and the absolute temperature T of the form χg=A/T+B, A and B being constants for each glasses. The results obtained by the spectrophotometric study show that the cobalt ions in glasses of lower than 50mol% of alkali oxide are in octahedral co-ordination, but that they are in tetrahedral co-ordination in glasses of more than 50mol% of alkali oxide. The magnetic moment is about 5.1 B.M. for the former and lower than 5.0 B.M. for the latter.
    The colour of the glasses varied from pink to blue with increasing temperature up to the softening temperature and the magnetic moment value of the glasses shows about 4.8 B.M.. There appears to be shifting of peak on the absorption band along the shorter wavelengths in the order from Li→Na→K→Rb, indicating different feature as distinct from that in silicate, borate and germanate glasses.
    The optical properties of the alkaline earth phosphate glasses were also determined.
  • クリープ強度およびクリープ破断強度
    大谷 隆一
    1969 年 18 巻 191 号 p. 752-757
    発行日: 1969/08/15
    公開日: 2009/06/03
    ジャーナル フリー
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