JOURNAL OF THE JAPAN WELDING SOCIETY
Online ISSN : 1883-7204
Print ISSN : 0021-4787
ISSN-L : 0021-4787
Volume 27, Issue 5
Displaying 1-7 of 7 articles from this issue
  • Mechanical properties of microstructures in HAZ
    H. Suzuki, H. Tamura, Y. Kawana, R. Hashiguchi
    1958 Volume 27 Issue 5 Pages 242-248
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    Mechanical properties of microstructures in weld heat affected zone have been studied in this third report by means of the synthetic specimens which were subjected to various weld thermal cycles in a reproducing apparatus as described in the previous report.
    Firstly, the effects of the maximum heating temperatures, 900, 1100 and 1300°C. and the keeping times, 3, 20 and 60 seconds at the peak temperature on the tensile properties of two high strength steels were investigated. The elongation and reduction of area were found to be decreased the more remarkably by the higher heating temperature over 1100°C., especially at 1300°C and by the more prolonged keeping at 1300°C. The reduction of area was reduced by keeping at 1300°C. for 60 seconds to 1/3 to 1/4 of the reduction of area of the specimen kept for 3 seconds, same with the weld thermal cycle.
    Secondly, comparison between the elongation of the synthetic specimen and the bend angle at crack initiation in Kommerell type longitudinal bead bend specimen was made for eight high strength steels. A close relationship has been found to exist between the two, and the elongation or reduction of area of the synthetic round bar tensile specimen has been concluded to be a good measure of the bend angle of crack initiation in Kommerell test.
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  • Behaviors of over-strained metals (Report 8)
    S. Morita, S. Goda
    1958 Volume 27 Issue 5 Pages 249-254
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    The effects of strain-aging on the 1st and the 2nd recoveries of the notch toughness of Al-killed, semi-killed and rimmed steel plates were investigated using the V-notched impact specimen. As the results of this experiment it was recognized that the 1st recovery is diminished by strain aging but the 2nd recovery not so much.
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  • I. Onishi, M. Mizuno, H. Hori, I. Koshizawa
    1958 Volume 27 Issue 5 Pages 255-259
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    In the previous report, authors confirmed the effects of the mixed ratio O2/C2H2, tip distance and plate thickness to the thermal efficiency of oxy-acetylene flame.
    In this report, continuously, the effects of the supplied heat quantity, numbers of nozzle in tip as shown in Fig. 1 and heating time to the thermal efficieney are measured with aforesaid apparatus and method.
    The test results revealed that ;
    1 The thermal efficiency of oxy-acetylene flame is decreased according to the increase of tip size and heating time, as shown in Fig. 6.
    2 The thermal efficiency is increased according to the increase of numbers of nozzle, in case the same heat quantity is supplied, as shown in Fig. 7.
    3 In case the heating is done till the center of plate surface, just below the white cone only, is melted, the total heat quantity which was absorbed in plate is decreased according to the increase of tip size and numbers of nozzle in tip.
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  • K. Matsuo, S. Yamajo, S. Adachi
    1958 Volume 27 Issue 5 Pages 260-263
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    The electrochemical potentials of the arc welded specimens prepared according to the differences of microstructures and the differences of the covered electrodes were measured in 3% and saturated NaCl solution. The experimental results were as follows :
    (1) There were significant differences between heat affected zone and other zones, but the differences between welded metal zone and base metal zone could not be found.
    (2) There were no significant differences among the electrode types.
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  • Y. Yamazaki, K. Wada
    1958 Volume 27 Issue 5 Pages 264-273
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    This investigation covers the determination of the optimum spot welding conditions by 3 Phase LowFrequency Resistance Welder for lm.m. LCN-155 and Inconel Sheets.
    LCN-155 and Inconel are both heat-resistance alloys for high-temperature use. Particulary for jet engine parts. LCN-155 has low melting point and high resistivity. In this paper above unique properties and their effects on spot weld are discussed.
    Because there is no standard that specify the properties of spot weld of such heat-resistance alloys, U.S. Military specification is applied to determine whether the spot weld is acceptable or not.
    The procedure for welding and testing are outlined, and the results of tension-shear test for spot weld are shown and discussed.
    Since sufficient electrode force was not obtainable with the available resistance welder, spot welding with more than 1, 500kg electrode force was not carried out. And so, effects of insufficient electrode force are discussed.
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  • K. Ando, J. Nishikawa
    1958 Volume 27 Issue 5 Pages 274-277
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    In this papea, we report the effect of IR drop in electrode and net arc energy on the so-called self requlating characteristics of MIG Welding. The radiant heat from molten pool of base metal is too small to explain the phenomena, as shown in the previous paper (Japanease W.J. Vol. 25 No. 2 1956).
    It must be noticed that, when we ajusted arc length shorter, the part of electrode from feeding contact point to, the arc becomes longer, in ordinary adjustment (Fig. 1-B). To separate the causes of the phenomena, we measured the melting speed when the arc length and wire length from the feeding contact point to the arc are changed respectively as shown Fig.1.
    According to our expeaiment, about 15% of the increase of the melting speed when the arc length is ajusted shorter, (which is the characteristics of the so-called self regulation), is due to the increase of the joule's heat above mentioned. See Table 1 & 2. Fig. 3 show the variation of the dorp along the wire of 100mm length when the same current is flowed. IR drop in Table 1 & 2 are estimated from those occillograms.
    The increase of electrode drop of arc when the arc is ajusted shorter, which is discussed in the previous paper, may explain to remainder.
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  • K. Ando, F. Ueyama, T. Manki
    1958 Volume 27 Issue 5 Pages 278-283
    Published: May 25, 1958
    Released on J-STAGE: June 12, 2009
    JOURNAL FREE ACCESS
    Melting speed of electrodes were studied on the following points.
    1) Effect of coating on S.P. and R.P. melting speed, (Fig.1, 2)
    2) Effect of surface treatments of bare electrode and preheating of electrode of organic coating, (Fig.3, 4, 5)
    3) Effect of short circuit, (Fig.6)
    4) Relation between D.C. component in A.C. welding and relative values of melting speed ofS.P. & R.P., (Table 2, 3)
    5) Irregularity of melting speed, (Table 4, Fig. 8)
    6) Relation of melting speed in A.C.D.C.S.P. and D.C.RP. (Fig. 9, 10, 11)
    7) Abnormal melting in higher current range, (Fig. 13)
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