材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
12 巻 , 112 号
選択された号の論文の9件中1~9を表示しています
  • 関 護雄
    1963 年 12 巻 112 号 p. 2-6
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
  • 長崎 勧, 渡辺 明
    1963 年 12 巻 112 号 p. 7-10
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
  • 米谷 茂
    1963 年 12 巻 112 号 p. 11-17
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    The boring method of Sachs is wellknown for the measurement of residual stress of cylinder. This method is not suitable to apply to hard specimens or those with small diameters. Moreover, there is a possibility of producing plastic deformation around the bore made in the center of specimen.
    In this report is explained a new method of the measurement of residual stress for the heat treated solid specimen with small diameters, which consists in eliminating the specimens from the surface by corrosion and then measuring the resultant change in the axial length and the specific volume.
    Let 0σz, 0σt, 0σr be the residual stresses in the axial, tangential and radial direction respectively and also let εz and εv be the strain in the axial direction and volume strain when the surface layer is eliminated.
    Then we have
    0σz=-E/1+ν{(εz+ν/1-2νεv)+fd/df(εz+ν/1-2νεv)}
    0σt=E/2(1+ν){(εz-1/1-2νεv)+2fd/df(εz-1/1-2νεv)}
    0σr=E/2(1+ν)(εz-1/1-2νεv)
    where E: Young's modulus
    ν: Poisson's ratio
    f: Sectional area of specimen
    The volume strain εv is, when we put v for specific volume after elimination
    εv=2(1-2ν)/3(1-ν)v-v0/v0
    in which v0 is the specific volume before elimination.
    The present report deals with the principle and the actual data of the measurements foregoing.
  • 木島 茂
    1963 年 12 巻 112 号 p. 18-28
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    Surface rolling of the specimen was achieved by pressing screw and three hard rollors having 20mm diameter and 12mm contour radius, screw pressure of 100kg or 150kg being applied.
    Fatigue strength was remarkably increased both in the corrosive environments and in air by surface rolling, but the effect was more pronounced in corrosive environments than in air, and in case of stainless steel, much more improvement of endurance was attained for austenitic steel than for ferritic steel both in 5% H2SO4 saturated with air at 25°C and in air.
    In slightly corrosive environment, even mild steel showed as good improvement as that of austenitic stainless steel, however in highly corrosive environment dangerous downward S-N curves were exhibited.
    It was postulated that improved endurance could predominantly be attributed to its suppressing effect against forming of hemispherical corrrosion pit, though residual compressive stress was favorable to prevent spreading fatigue fissures, and this interpretation was supported by micrographic examinations and potential measurements.
    As a conclusion, general effects of surface rolling on corrosion fatigue, presumably, involve three ways; firstly in a corrosive environment in which a metal is fully protected by corrosion product or by passive film, more stress concentration would have been resulted which initiated fissures due to more predominant effect of rapid contraction of anodic area than effect of ready decrease of general corrosion, as was pointed out by Gould and Evans, and aggravated endurance would be resulted; secondly if a metal could be freely soluble, stress concentration also could be avoided and prolonged corrosion fatigue life would be temporarily, resulted; thirdly, if a corrosive medium offered marginal property to a metal, effective control against initiation of corrosion pit would be resulted, without causing dangerous stress concentration and the highest protection against corrosion fatigue could be attained.
    Inferring from serious damage observed in shrink fitted austenitic stainless steel into hard steel, the same deterioration of corrosion fatigue would be expected in other cases of such cladding or overlaying.
  • 八木 明
    1963 年 12 巻 112 号 p. 29-37
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    In order to find out the defacement prevention effect of the material when it is used for points of the railway, the author conducted a test, using an Amsler-type abrasion testing machine, at slip velocities of or 15cm/sec, and under contact pressures of 50∼90kg/mm2.
    The test piece of type is about 0.7%C standard structure steel, and the other materials of deposited weld metals are austenitic high manganese steel, high Mn-Cr steel, high Mn-Ni steel, and high Mn-Mo steel etc.
    The result of this test shows, in case of austenitic structure of deposited weld high manganese metal, the same tendency of wear as high manganese steel.
  • 長崎 勧, 渡辺 明, 吉崎 一弘
    1963 年 12 巻 112 号 p. 38-42
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    The authors studied the influence of zircon on the reaction between alumino-silicate materials and magnesium oxide for cordierite formation in the fire clay refractories.
    Specimens were fired at SK 14 (1410°C) in a tunnel kiln for 40 hours. The measurements of thermal expansion and linear changes of the specimens by reheating were carried out. The crystal phase of the specimens were examined by X-ray analysis.
    The results obtained are as follows:
    (1) By the addition of zircon to the mixture of clay and magnesium oxide the following reaction is promoted at about 1400°C,
    3(3Al2O3·2SiO2)+6(MgO·SiO2)+5SiO2→3(2MgO·2Al2O3·5SiO2).
    (2) The formation of glassy phase in the refractories is inhabited by the promoting the above reaction.
    (3) The inversion of hexagonal form to orthorhombic form of cordierite is caused by such addition of zircon.
  • 河本 実, 仲嶋 浩, 田中 道七
    1963 年 12 巻 112 号 p. 43-52
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    Recently much attension has come to be paid to the thermal fatigue phenomenon of materials by many investigators, because of the rapid development of machines operated at high tem perature, and a number of papers have been issued on this subject. But the thermal fatigue is considered to be one of the most complicated problems, because two important factors, strain and temperature, completely overlap in this phenomenon. Therefore, some more advanced and more systematic investigation has become necessary to obtain much more useful informations about it.
    The authors, being interested in this problem, constructed for trial a new thermal fatigue testing machine in order to obtain systematic informations, because the testing equipments used by many investigators were in most cases nearly the same type as that originally made by L.F. Coffin, and no substantial development had not been made.
    Main feature of this machine is, among other things, to be able to independently apply the strain cycling and the heating cycling to the specimen. So the effect of each factor can be pursued systematically with this machine. Furthermore, these two cycles can be synchronized with arbitrary phase difference, and the strain rate, heating or cooling speed and hold times may be adjusted to the desired values. Several thermal fatigue tests were carried out on the annealed high carbon steel using solid cylindrical specimens.
    Test result are as follows;
    (1) All performances of the machine and the controlling circuits are very satisfactory ones.
    (2) Effects of specimen size on thermal fatigue life are small.
    (3) Thermal fatigue life is decreased with the increase of maximum temperature when mechanical strain is maintaind constant.
    (4) Effect of radial temperature distribution of solid specimen on thermal fatigue life is negligible when mechanical strain is superimposed
  • 楠本 韶
    1963 年 12 巻 112 号 p. 53-58
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    Investigation was performed on the effects of degree of restraint on thermal fatigue life of steels. Relations between strain amplitude, stress amplitude and cycles to failure were confirmed, using Coffin type thermal fatigue testing apparatus for some cast steels and 18Cr 8Ni stainless steel. Based on these relations then, the effects of restraint on thermal fatigue life and on some other factors were calculated.
    The results indicate that, although the alleviation of restraint is effective to prolong the thermal fatigue life, the degree of the effects varies remarkably according to the kind of materials and the amount of strain amplitude.
  • 上田 太郎, 松尾 哲夫
    1963 年 12 巻 112 号 p. 59-64
    発行日: 1963/01/15
    公開日: 2009/06/03
    ジャーナル フリー
    In the last paper, authors reported that the torsional working temperature has a remarkable influence on the torsional creep limit of a plain 18-8 stainless steel. Through the present investigation, measurement of torsional creep limit of a 18-8 Cb Stainless steel bar (5mmφ×50mm) austenized and twisted to a degree of 0.128π/cm or 0.256π/cm was made at 500 and 600°C, and then hardness and micrographic testing and X-ray analysis were carried out. These results obtained are summalized as follows:
    Torsional creep limit of a 18-8 Cb stainless steel is not so much affected by the torsional working temperature of -60∼800°C as in case of the creep limit of plain 18-8 stainless steel.
    In this 18-8 Cb stainless steel, it was found that the effects of torsional working temperature on the difference of the hardness before and after creep testing and also on the precipitation mode of Cb-carbide (CbC) were small.
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