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Volume 16, Issue 7
Displaying 1-15 of 15 articles from this issue
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Hakaru Masumoto, Hideo Saito, Makoto Sugihara1952 Volume 16 Issue 7 Pages 359-361
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe specific heat of the 7 alloys in α-solid solution range of copper and zinc system was measured in annealed and quenched states by an invers rate curve method. The specific heat-temperature curves of the alloys generally show a slight anomaly at about 200° to 260°; the anomaly is most conspicuous in the alloy containing 30.35 percent of zinc. And, while the temperatures of the knick points on the curves of the alloys containing less than 20.75 percent of zinc are almost constant, they become lower when the content of zinc is increased to more than 20.75 percent. This anomaly can be prevented by quenching from 500°. Thus, it has been concluded that the anomaly may be caused by the existence of the superstructure Cu3Zn in a short range and not by the change of the solubility of α-solid solution.View full abstractDownload PDF (412K) -
Genjirô Mima, Shigenori Hori1952 Volume 16 Issue 7 Pages 361-365
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSGenerally, the industrial alloys consist of several phases, for example, as solid solution, intermetallic compound and non metallic inclusion. Therefore, the deformation process of those alloys by rolling differs from that of alloys with homogeneous structure, and then the internal stresses occur. We studied the deformation process of the 2nd phase due to rolling on Cu-Zn, Cu-Sn, Cu-Al and Sn-Sb alloys of composition with two phases. The experiments have been described by statistical methods using a microscope.
The results obtained are as follows: in alloys consisting of a softer or a harder 2nd phase with the matrix, a softer 2nd phase undergose greater deformation than the matrix and a harder one tends to deform less than the matrix. The rolling goes forward leading to a similar behavior is flow strength of the both phases with progressive reduction. The following equation which corrected Unckel’s formula contained these experiments, \fracΔhh⁄\fracΔHH=Q1−Vi⁄Vm, where Δh⁄h is the deformation degree of the 2nd phase, ΔH⁄H the average percentage reduction of the test-piece, Vi⁄Vm the relative hardness of the both phases and a is obtained by the experiment, and in our investigation a is 3.0. If the 2nd phase particle has an irregular shape, the flow of the matrix is disturbed remarkably and the defect of the material shows a tendency to increase with rolling.View full abstractDownload PDF (790K) -
Nobuhiko Kunitomi, Teruko Ogura1952 Volume 16 Issue 7 Pages 365-369
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe change of internal friction accompanied by the recovery of cold-work in aluminum was measured and compared with the changes in other physical properties, namely, hardness and thermoelectric power. The results show that (1) internal friction increases monotonously with the increase of cold-work, (2) the values of internal friction and other properties decrease exponentially by annealing, the relaxation times and saturation values of the exponential curves are functions of annealing temperatures, and (3) the internal friction changes remarkably by low temperature annealing but other physical properties do not change. These results were explained by considering that the internal friction is caused by the viscous behavior of grain boundary which consists of many kinds of lattice defects.View full abstractDownload PDF (610K) -
Shigeo Muromachi, Hiromichi Inoui, Kazuhiro Moriyama1952 Volume 16 Issue 7 Pages 369-373
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe authors carried out the bending test of 13 Cr steel with different sizes. The process of the bending test studied was divided into the following four steps:
[] (1) The elastic bending: (2) Inner radius of the specimen contacts with the jig radius: (3) The bending angle moves up to 150°: (4) After 150°, the loading direction changes to right angle to before and bending to 180°: The experimental results showed that the bending rate of angle proportionates with the partial maximum elongation in the second period, and after the 3rd period, theoretically the following equation has been found, desmax⁄dx=0. Inotherwords, the partial maximum elongation shows to be constant during this step. And furthere testing has been found to be useless.
The critical value of es is obtained by the following term, h⁄(rj+h), where h is half thickness of specimen and rj is jig’s radius. For this purpose we must use a specimen with suitable thickness and decide the proper length of jig’s radius corresponding to the specimen being hard or soft, and the length of supporting rollers also.View full abstractDownload PDF (719K) -
Yoshimi Tanabe1952 Volume 16 Issue 7 Pages 374-378
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis method is applied to iron, steel, special steel, cast iron and cast steel. And this replica is made easily by two step processes, and it is very accurate at the displacement of the structure. In this method, we need not cut off the sample from the testing materials. This replica is made by the following order and method.
(1) Cu is plated by the electro chemical displacement on the surface of testing material. (2) Cu-replica is stripped off from testing material by the use of methylmetacrylate adhesive on the celluloid plate. (3) SiO2 vapour is fixed on the Cu-replica. (4) Cu-SiO2 replica is stripped off by chloroform-benzene sol. (1:1) from celluloid plate. (5) Cu-SiO2 replica is cleansed by alcohol. (6) Cu is dissolved by dilute nitric acid (1:1.5). (7) SiO2-replica is cleansed by distilled water. (8) SiO2-replica is floated in distilled water and SiO2-replica is fixed on the sample holder. This replica method is named Cu-SiO2 method and this method has advantages which will be shown in next item. (1) SiO2-replica need not cast shadow and SiO2-replica is in good contrast. (2) SiO2-replica has the shadowing effect which has very clear and short shadows. (3) Cu-replica can be immediatly examined by optical microscope.View full abstractDownload PDF (970K) -
K. Monma, S. Uemura, M. Hirata1952 Volume 16 Issue 7 Pages 378-382
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is well known that the resistivity of quenched steel is much higher than that of annealed one. Especially in the cases of high speed steel and K. S. magneto-steel, the values of quenched state are remarkably high.
Hitherto it has not been throughly explained in what process such high resistivity condition was accompanied by Ar″ transformation.
The authors measured the electrical resistance change during Ar″ transformation of high speed steel and some other special steels. And the following results were obtained: (1) The resistivity increased remarkably in Ar″ transformation, (2) but even in the case of Ar″ transformation, when the occurring temperature was some what higher than a certain critical value,—which varies with the kind of steels—, the resistivity showed a remarkable decrease with the transformation.
The transformation of type (2) was notationed Art″. The main cause of resistivity increase accompanied by Ar″ transformation may be explained as being due to the high resistivity of supersaturated α-solid solution. In the case of Art″ the transformation temperature was so high that the transformed supersaturated α-solution could not hold its own state, consequently, the carbide precipitated out of it. This is the reason why the resistivity decreased in Art″ transformation.View full abstractDownload PDF (775K) -
Kiyokazu Ogawa1952 Volume 16 Issue 7 Pages 382-386
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe wearing phenomena of eutectic graphite cast iron was inspected by means of examining slide-worn specimens when treated with a lubricant, and then compared with pearlite cast iron in various ways. The wear of cast iron is so intricate that even if wearing condition is the same, the wear is variant as quality, structure, strength or stress, or sometimes hardness or roughness or the surface to be worn can not be equalized exactly. After completly observing them, wearing conditions which are mainly dependent upon pressure and velocity of wear are pre-determined and under these conditions the results are distinguished as follows: the wear of eutectic graphite cast iron is different from that of pearlite cast iron; initial wearing amount of eutectic graphite cast iron is not so apparent as that of pearlite cast iron and after a definite running the worn zone increases with running distance almost proportionaly.
It is said hitherto that ferrite structural cast iron is inferior to pearlite structual cast iron regarding the resistant property of wear. The author has recognized this fact, but it can be said that this is dependent upon the wearing pressure and under a light load wearing the wearing resistance of eutectic graphite cast iron is much superior to that of pearlite cast iron. In the wear in the parts of sewing machine, several practical examples on this validity can be seen. Under the wearing conditions in which a part to be worn consisted of eutectic graphite cast iron and carbonitrided steel, various phenomena have been cleared and proved that eutectic graphite cast iron is more logical to use as cast iron for a sewing machine part in considering the resistance of wear, machineability and stress.View full abstractDownload PDF (826K) -
Isao Aoki1952 Volume 16 Issue 7 Pages 387-391
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAdding the Cu-Mg alloy to the molten pig iron, the alloy being the small particles in liquid state, dispersed in the molten pig iron (Fig. 4, 5, 6). When Si was added to the condition of molten pig iron as the inoculant, graphite in the molten pig iron precipitated on the surface of the liquid particles of Cu-Mg alloy and spheroidized (Fig. 9, 10, 11). Then, the Cu-Mg alloy dissolved mostly in the molten pig iron with time.View full abstractDownload PDF (1049K) -
Yachiyo Kakita, Michiko Namiki1952 Volume 16 Issue 7 Pages 391-393
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSReduction of arsenic was studied by the use of chromous, titanious and molybdenum solutions reduced with liquid zinc amalgam. Arsenic was reduced to metallic state with chromous solution in hydrochloric acid or hydrochloric acid solution containing sulfuric acid but not with titanous or molybdenum solution reduced. Arsenic obtained by reduction was estimated by iodimetry and gravimetry. Appling this method, the arsenic in iron was determined accurately and rapidly.View full abstractDownload PDF (366K) -
Hidehiro Gotô, Yachiyo Kakita1952 Volume 16 Issue 7 Pages 394-395
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe determination of free lime in slag was investigated. Generally the free lime in cement is determined by Lerch and Bogue’s method or McPherson and Eorbrich’s method. Appling the McPherson and Forbrich’s method by the use of ethylen glycol, the determination of free lime in slags was studied. The powdered slags was warmed up to 60∼70°C with ethylen glycol to extract free lime, and after it was filtered, the filtrate was titrated with standard hydrochloric acid (0.1 N) to estimate free lime. By this method, free lime in several kinds of slags and cement was determined and the results obtained were shown. This determination was carried out successfully within about a half an hour without any complicated procedure.View full abstractDownload PDF (316K) -
Rihei Kawachi, Kiyoshi Shinoda1952 Volume 16 Issue 7 Pages 396-400
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt has been known that the variation of tensile properties depending on the pulling speed was great for rolled zinc sheet but small for annealed one, i.e., the former was superior in tensile strength and inferior in elongation to that of the latter when tested at low pulling speed while such superiority or inferiority was reversed at high pulling speed.
To confirm this abnormal phenomenon in detail, tensile properties of the alloys quoted below were tested at the rate of tension of 1∼140 mm/min after various annealing treatments.
(a) highly cold rolled zinc sheets containing 0.6 pct lead. (b) zinc-lead (0∼1.14 pct) alloys sheets of which cold reductions were 0∼70 pct. (c) highly cold rolled zinc alloy containing small amount of lead and manganese.
The results obtained were as follows:
(i) the abnormality above mentioned was clearly shown in alloy (a), but not so clear in (b) and not recognized in (c).
(ii) it was shown that degree of the variation of tensile properties depending on the rate of tension became smaller with proceeding the recrystallization of specimens.
(iii) the specimens of alloy (c) annealed at 200∼325°C showed the hardening phenomenon when tested at the rate of tension of 1∼100 mm/min, the temperature at which the max strength was obtained was decreased with increasing rate of tension. And at the rate of tension of 140 mm/min. Such increase of strength was disappeared.
To clarify such abnormal phenomena it was suggested that further researches into rolling schedule, reducing amounts or the effect of testing temperature must be done.View full abstractDownload PDF (939K) -
Yûkô Mitani1952 Volume 16 Issue 7 Pages 401-404
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCarburized steels have large amount of internal stress near the surface, which will be defects when used. In order to decrease internal stress low temperature tempering (about 150∼200°) was used to be enployed after quenching. From the same point of view, induction surface hardened steels must be tempered at low temperature; however, the hardness of induction surface hardened steel decreases greater than with the conventional quenching.
Two reasons must be considered about this problem; the first is internal stress and the second is the metallurgical properties of rapid heated unstable martensite; however, the martensite of induction hardened sorbitic steels did not show any extraordinary softening at low temperature and the hardness change was nearly equal to the conventional quenching, and so the uniformity of martensite must have decided the stability of martensite.
In this paper the author described this problem.View full abstractDownload PDF (985K) -
Shôzô Saitô, Kunio Okabayasi, Tukasa Tanaka1952 Volume 16 Issue 7 Pages 404-409
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSWe investigated the wear of the nodular graphite cast iron, using Nisihara’s wear testing machine, to determine the wear when it is used for the cylinder liner of diesel engine. It was found that, without lubricant, the wear of the nodular graphite cast iron against steel and cast iron was smaller than that of the flaky graphite cast iron, and also good properties to resist wear were obtained in the case of oil lubrication. It became clear that the nodular graphite cast iron with pearlite matrix have more superior properties than that of the other structures.View full abstractDownload PDF (936K) -
Gorô Ohira1952 Volume 16 Issue 7 Pages 410-412
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe investigation isintended to find how the molten metal flows in horizontal quadrilateral mould. The measuring method is as shown in the last reports.View full abstractDownload PDF (338K) -
H. Nishida1952 Volume 16 Issue 7 Pages 412-415
Published: 1952
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the factorial ore analysis of local research offices, I have stochastically considered the random, personal and sampling error, and from the results of the experiment the following conclusion was obtained: the personal error was of no significance when the level of significance was 0.05, and the random also was precise.
But the sampling precision was so bad that the analysis error happened to sample couldn’t be neglected.View full abstractDownload PDF (534K)
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