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Volume 20, Issue 6
Displaying 1-16 of 16 articles from this issue
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Tomo-o Sato, Saburo Toya1956 Volume 20 Issue 6 Pages 297-300
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn graphitic steel containing Si, the carbide phase is unstable because of the high Si content of the steel and consequently it may easily decompose by heat treatment, but when the steel contains other elements, the graphitization characteristics may be expected to change. Therefore in this report, the experiments were carried out on forgeability, the graphitization, the change of hardness and the micro-structure of graphitic steel (1.3∼1.5%C, 1.5%Si) specimens containing 0.2∼1.0%Ti, 0.2∼1.0%V and 0.003∼0.1%B respectively by graphitization annealing at elevated temperature. With increasing Ti and V the forgeability of these steels rise and the power of graphitization of Ti is slightly negative and that of V strongly negative. While by increasing B the forgeability of the steel becomes poor, and the amount of graphite decreases. As above, the limit of alloying composition in graphitic steel containing 1.5%C and 1.5%Si is determined as within 1%Ti, 0.5%V and addition of B is unnecessary.View full abstractDownload PDF (713K) -
Tadakazu Sakurai, Tadashi Kawasaki, Hisashi Izumi1956 Volume 20 Issue 6 Pages 300-304
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe results of the present study on the effects of stress-aging treatment upon the static strength of mild steel are as follows: (1) The higher the stress applied to the specimens during stress-aging treatment, the more effective the hardening, but the intensity of stress has little influence on the tensile strength and the yield point, if any. (2) A remarkable increase in hardness and static strength is obtained by pre-straining at temperatures between 250° and 500° before stress-aging at those temperatures, and if rapid cooling after stress-aging treatment is carried out under loading, the hardness and the strength increase still more. (3) The most effective method of improving the static strength of mild steel is to heat the specimen at about 400°, to apply an adequate load to it at that temperature so as to make suitable plastic deformation and then keeping the load constant for a suitable time, cool it rapidly under that load. In this case the most favourable aging time is a function of the aging temperature, and as to the mild steel used here, it is about 5 and 2 minutes for 250° and 400° aging temperatures, respectively.View full abstractDownload PDF (706K) -
Waichi Ota1956 Volume 20 Issue 6 Pages 304-308
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe distribution of fibrous flow in transverse sections of high carbon chromium steel, hot rolled by some groove profile was studied, and in addition to this, the relation between the defects, such as, decarburized layer, wrinkles and cracks which are generated on the surface of rolled materials and the distribution of fibrous flow was investigated in this report.View full abstractDownload PDF (952K) -
Yoshinobu Sawada1956 Volume 20 Issue 6 Pages 308-311
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe corrosion resistivity of thirteen percent chromium steels in week acid river water is conciderably good, but it differs by heat-treatment, so we have studied on the effect of heat-treatment on corrosion rate of these steels. When they are tempered at several temperature after rapid cooling from γ phase, the corrosion rate increases very much by tempering between 500∼600°, especially at 550°. This is due to the decrease of chromium concentration by the precipitation of chromium carbides. But when they are tempered at more than 700°, the corrosion rate decreases again, we think that this is due to the fact that the concentration of chromium in the matrix becomes uniform by the tempering at high temperature. The welded parts in these steels are deeply corroded, but when they are tempered above 700° after welding, the corrosion in the welded parts can be prevented. The welded parts on 13% Cr-steel added with 1% titamium are not corroded even in fresh-welded state.View full abstractDownload PDF (683K) -
Rihei Kawachi1956 Volume 20 Issue 6 Pages 311-315
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of Ti (up to 3%) on the various Cu-binary alloys Cu-Si (<5%), Cu-Al (<10%), Cu-Mn (<20%), Cu-Sn (<8%), Cu-Zn (<40%), Cu-Ni (<2%) were studied. At first, the macro-structure and the hardness were examined in these ingots in as cast condition, then the ingots were annealed and cold worked in to 0.8 mm sheets. The hardness of the specimens at annealed, or quenched and tempered condition, the micro-grain size of in annealed one, and the corrosion resistivity against 10% NaOH, 5% HCl, 5% H2SO4, 6%NaCl+0.3%H2O2 (Pct. of HCl and H2SO4 means vol. Pct. assuming commercial conc. were 100 Pct.) were tested. The results obtained are as follows: (1) In any alloy series, Ti refines the structure and increases the hardness of ingot. This hardening effect decreases with increasing the amount of the third element. (2) By addition of Ti, the hardness of any rolled or annealed sheets is increased as the grain is refined and the grain growth is inhibited. (3) The large temper-hardenability of binary Cu-Ti alloy decreases with increasing the amount of any third element. (4) The effect of Ti on the corrosion resistivity is not so marked but, on datails there is some room for further study.View full abstractDownload PDF (626K) -
Yashichika Ôto, Takanobu Hamaguchi, Chujo Matsumoto, Taira Yoshi ...1956 Volume 20 Issue 6 Pages 315-319
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAs to the application of the quantometer for the analysis of iron and steel, the previous reports contained the results concerning low alloy steel, cast iron and high alloy steel by means of multisource spark-like discharge; and in this report the authors studied the spark method of arc-like discharge for the purpose of quantitative analysis of small contents in iron and steel such as B, Al, Sn and Cr, obtaining satisfactory results. As the standard samples we used pin type pieces of N.B.S. (7/32″), and the arc-like discharge of C2 50 μF, R2 50 and L2 360 mH. The spectral lines of B and Sn were disturbed by the spectral line of Fe, but this trouble could be eliminated by the use of second order line and arc-like spark method; and furthermore the back-ground was of the order of negligible weakness though we could not measure it. Although the quantitative analysis of small contents of B. Al, Sn and Cr was difficult by means of the spectrographic method and chemical analysis, it became easy and rapid by the adoption of arc-like condition and photoelectric method, within the standard deviation, of 2 to 10%.View full abstractDownload PDF (636K) -
Hidehiro Gotô, Yachiyo Kakita1956 Volume 20 Issue 6 Pages 319-322
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSContinue from our previous research, the photometric determination of microquantities of tin in iron and steel was investigated. Tin was separated from large amounts of iron by co-precipitaing with manganese dioxide as described in the previous papers. Then the photometric determination was made after extracting its diethyldithiocarbamate complex with organic solvent. By this method, estimation of 0.001% content of tin was possible using 1 g of sample.View full abstractDownload PDF (594K) -
Kokichi Sano, Kazuhisa Okajima, Naoki Okuda1956 Volume 20 Issue 6 Pages 323-325
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe activities of silicon and copper in their molten alloys were calculated from the measured electromotive forces of concentration cells of the type \ominusSi|SiO2-CaO-Al2O3|Cu-Si⊕ at 1470° and 1510°, and it was made clear that the alloys show a negative deviation from Raoult’s law.View full abstractDownload PDF (396K) -
Zenji Nishiyama, Ken’ichi Shimizu, Shin’ichi Satô1956 Volume 20 Issue 6 Pages 325-328
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAccording to the theory of the mechanism of martensite transformation, slipping or twinning should occur in a martensite crystal during the transformation. With the object of offering some data to the theory, an electron-microscopic examination has been carried out, using Fe-30%Ni alloys. The results are as follows: In the surface relief of the martensite there have been found fine parallel bands which are parallel to (112)M and have a spacing of about 0.02μ at the smallest. On the etched surface, however, any such bands have scarecely been found except in the vicinity of the mid-rib.View full abstractDownload PDF (652K) -
Kenzi Ikeda, Shirô Ogawa1956 Volume 20 Issue 6 Pages 329-332
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe α(c.p.h.)\ ightleftarrowsβ(b.c.c.) transformation of titanium was observed by electron emission microscope, the specimens in a form of strip being directly heated by electric current and activated by (Ba,Sr)O. Surface striations observed in a α grain after cooling from high temperature did not readily vanish by reheating at temperatures above the transformation point and it took several hours before they became faint at 1000°. This behaviour of the striations does not conflict with the interpretation of Williams et al. that they arise from the accommodation slip accompanying the transformation. A one to one correspondence seems to be kept between α and β grains in the case of slow change of temperature. But this is not so in the case of rapid change of temperature, i.e., several orientations of striations occur in an original β grain in the case of cooling.View full abstractDownload PDF (842K) -
S. Sakui, K. Sato, K. Akiba1956 Volume 20 Issue 6 Pages 332-336
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPolycrystalline aluminum sheets of the size 1×5×70 mm were elongated by falling weight, which had the maximum falling height of 4 m. The time-load curve during deformation was taken by a system of piezoelectricity-cathode ray oscillographs. The sign of propagation of plastic wave through the test piece was seen on each time-load diagram. The effect of the rate of deformation on the tensile strength and the elongation and the effect of grain size on the static and dynamic tensile properties were observed.View full abstractDownload PDF (716K) -
Masayoshi Tagaya, Imao Tamura1956 Volume 20 Issue 6 Pages 336-339
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe severity of quench, H, was determined for several quenching media by a quenching test with cylindrical specimens of carbon tool steel (SK6) and of ball-bearing steel (SUJ2) in a series of sizes according to the Grossmann’s method. The results are shown in Table 3. The values of H obtained are examined from several angles and some arguments as to the accuracy of Grossmann’s method of approximation are also presented.View full abstractDownload PDF (711K) -
Tomo-o Satô, Taiji Nishizawa1956 Volume 20 Issue 6 Pages 340-344
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt has long been recognized that Curie point of cementite (Fe3C) changes due to containing special elements in solid-solution, but little work has been done on the quantitative investigation of this problem. In the present studies, thermo-magnetic experiments were carried out on cementites isolated from various alloyed steels, and the following results were obtained: (1) Curie pt. of cementite (A0) and the concentration of the third elements (⟨M⟩%) in it are related as A0(°C)=215+p⟨M⟩, where p is determined as follows: Co; 8.7, Ni; 3.7, Cr; −16, Mo; −16, W; −19, Mn; −24, V; −57. (2) The descent of A0 pt. due to dissolving of Mo, W, V and Ti halts at 186°, 191°, 181° and 213°, respectively. From this results, it is concluded that the solvilites of these elements into cementite are restricted within 1.8%Mo, 1.3%W, 0.6%V and 0.1%Ti (at 700°). (3) Si, Al, S and P slightly lower the A0 pt. This fact may be taken to prove the possivility of dissolution of these elements into cementite.View full abstractDownload PDF (591K) -
G. Yokoyama1956 Volume 20 Issue 6 Pages 344-347
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCorrosion of tin in sulfuric acid solutions below 30% is considered as a simple oxygen depolarizing type of corrosion. In the acid above 30%, however, the influence of atmosphere change and the stirring effect on corrosion are not explained by the depolarizing mechanism. Various experiments were carried out and it was concluded that the cause of these abnormal corrosion phenomena is ascribed to the depolarizing action of sulfate ions which are reduced on the surface of the corroding tin.View full abstractDownload PDF (631K) -
Tokushichi Mishima, Ryukiti Hasiguti, Yasuo Kimura1956 Volume 20 Issue 6 Pages 347-350
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe age-hardening process of nickel-14∼16% tin alloys was studied. The specimens were quenched in water and aged at 550∼625° for various lengths of time. Their magnetic properties, Vickers hardness, lattice parameter and microscopic structure were observed during the age-hardening process. The behaviors of the intensity of magnetization temperature curves and the changes of the lattice parameter give evidences for discontinuous precipitation. The fractional changes of the coercive force and the Vickers hardness are identical with each other at respective aging temperatures except in the early stage of aging. The changes of properties can be described by the Austin-Rickett equation; p⁄(1−p)=ktn. The activation energy of the aging process in this alloy is 33,000 cal/mol.View full abstractDownload PDF (627K) -
Ryoichi Nozato1956 Volume 20 Issue 6 Pages 351-355
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe aging process of 10%Sn-Pb alloy at room temperature was studied by specific heat measurements. (A) Precipitation of tin from super-saturated solid solution takes place in two stages. 1) The first stage; About 66% of the excess of tin are depleted and a metastable equilibrium is attained. 2) The second stage; The remaining 34% of the tin are depleted and a stable equilibrium is attained. (B) The stable equilibrium is not attained by slow cooling from high temperature at a rate of about 1.5°/min. The stable equilibrium is attained in single stage during aging of slow-cooled alloy. (C) A recrystallization with re-solution of tin was observed at about 146° on re-heating an aged alloy.View full abstractDownload PDF (1083K)
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