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Volume 21, Issue 1
Displaying 1-17 of 17 articles from this issue
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Hidetake Kusamichi, Yoshiro Yagi, Toru Yukawa1957 Volume 21 Issue 1 Pages 1-10
Published: 1957
Released on J-STAGE: April 04, 2008
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Itsurô Tatsukawa1957 Volume 21 Issue 1 Pages 11-14
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this article, in order to obtain fundamental informations on the applicability of hot-bath quenching below Ms temperature for improvement of mechanical properties of steels, the dilatation during isothermal treatment at various temperatures both above and below the Ms point as well as during tempering following the hot-bath quenching and the microstructures were observed in a 0.8%C steel, and the structural constituents after these quenching were determined. The isothermal dilatation curve at any temperature below the Ms point has two steps. At the first step occurring in the initial stage at every temperature, athermal and isothermal martensite is formed. The second step signifies the isothermal lower-bainite reaction accompanied by the remarkable stabilization of austenite in the similar way as the isothermal reaction in austempering above the Ms. The structural constituents at room temperature after hot-bath quenching vary with holding time at a given temperature according to the isothermal transformation above mentioned, and hence, structures consisting of tempered martensite plus Jower-bainite containing a lot of retained austenite are obtained by means of isothermal treatment under certain conditions.View full abstractDownload PDF (638K) -
Akira Takaoki1957 Volume 21 Issue 1 Pages 14-18
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUltrasonic inspection is now firmly established as an inspection method of large forgings, such as generators and turbine rotor forgings, and the sound waves vanging from 1 to 3 megacycles per second have ordinarily been used in our country. But if the forgings were unsuitably heat-treated, ultrasonic inspection could not be taken into service. Therfore, the attenuation of ultrasonic waves in 3%Ni-Mo-V steel with various structures was measured. The attenuation measurement was made by multiple bottom echoes in steel , using water buffer between the specimen and the transducer. All the specimens were heat-treated by isothermal transformation at 600°, various austenitizing and modified austempering. The attenuation was measured at each stage of transformation process by 3 megacycles. The results obtained were as follows : (1) Extremely large austenitic grain sizes (about 1 mm) and coarse grains cause the greatest attenuation in the steel even if the back ground is bainitic structure. (2) Ferritic net-work decrease the transmissibility of ultrasonic wave. (3) The pearlitic structure formed by isothermal transformation has better transmissibility than the coarse austenitic grains with back ground of bainitic structure. (4) Austenitic grain refining is an important factor in special steel, and modified austempering is the most suitable heat-treatment for ultrasonic attenuation and mechanical properties.View full abstractDownload PDF (1004K) -
Masazô Okamoto, Renpei Yoda1957 Volume 21 Issue 1 Pages 18-22
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of various inoculants on molten irons were investigated, the results being as follows: (1) For common iron of low C and low Si, the inoculating effect of Ca-Si is superior to that of Si, but against Mg-treated iron, Ca-Si is inferior to Si. Inoculants like Ca-Si are inadequate for the inoculation against strongly deoxidized iron like the Mg-treated one. (2) Fine inoculants are easily oxidized on the surface of molten iron and the effect is generally weaker than that of coarse granular inoculants. While,the addition of fine Cr causes submicroscopic suspensoid of Cr2O3 in molten iron and promotes its graphitization. (3) Si-alloys containing small amount Al or Al plus Ti show strong inoculating effects on iron having nitrogen as well as on common iron of low C and low Si. The order of the inoculating effect on common iron of low C and low Si is Si-Al-Ti>Si-Al>Ca-Si>Si>Al>Ti, and that against iron high in nitrogen is Si-Al>Si-Al-Ti>Al>Si>Ti.View full abstractDownload PDF (892K) -
Yû-ki Shirakawa, Takeshi Miyazaki1957 Volume 21 Issue 1 Pages 22-24
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe magnetic properties of spheroidal and fiake graphite cast-irons of similar composition, cast into sand moulds of various diameters, were measured, and the results obtained were as follows. At the degree of graphitization, the maximum induction B100, the coercive force Hc and the hysteresis loss Wh of spheroidal graphite cast iron are lower than that of flake graphite cast iron, and so the maximum permeability μm and the residual induction Br were higher. B100, Br, Hc and Wh decrease and μm increases with increasing degree of graphitization.View full abstractDownload PDF (661K) -
Yasuyuki Toba, Humio Hataya, Haruo Katô1957 Volume 21 Issue 1 Pages 25-28
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe authors carried out the experiment on wire drawing with back tension of copper, 8/2-red brass, 7/3-brass, 65/35-brass and 6/4 brass. The effects of back tension on the drawing characteristics, the mechanical properties, the secular change phenomena and the texture were investigated. The energy consumption and the die pressure decreased with increasing back tension. The tensile strength of the drawn wire was scarcely affected by the back tension. However, the elastic properties were influenced by it, though the degree of the effect was somewhat different by the composition of the alloys. The dispersion of the textures, ⟨111⟩+⟨100⟩, could be reduced by increasing the back tension applied.View full abstractDownload PDF (637K) -
Genjirô Mima, Masahiro Meshii1957 Volume 21 Issue 1 Pages 28-32
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThis study was carried out with a view to throwing light on the behavior of the second phase as a slip interference and its influence on further treatments. Samples of (α+β) brass were cold-rolled and the hardness changes of α and β were measured respectively by using a micro-hardness tester (50 g load). Comparing th hardness vs. The reduction curve of β in two-phase alloy with that of a specimen consisting of a single β phase, we observed that the reduction of β in the softer matrix was delayed and the relation between the reduction of β in α matrix and the average reduction was found by using hardness as a parameter. On the other hand, the difference between the curves of α with β and without β was small, since the greater influence of β might be limited in its vicinity and we could not measure it well with 50 g load. Inequality of micro-hardness distribution in the matrix has its maximum point between 50% and 60% reduction. The deformed samples mentioned above were annealed to 200° and 300° for various periods of time, and we examined their hardness in the same way as that during the deformation process. For instance, in samples of 80% reduction, β was softer than α at every stage of annealing at 200°. At 300°, both the hardness of α and β recovered to the values found before the reduction, and β softened faster than α. Further-more, β was softer than α at the earlier stage and then became harder after the middle stage, about 1000 sec. And it was found that the deviation of each measured value on the α matrix from the mean increased at the recrystallization.View full abstractDownload PDF (681K) -
Susumu Morioka, Teijiro Shibata, Akimi Umezono1957 Volume 21 Issue 1 Pages 32-35
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSBlack titanium powder is electrodeposited from aqueous solution of (NH4)2TiF6. Since electrolytic titanium powder is very fine,it is very active and is oxidized rapidly in air at room temperature. This oxide film is very thin, non-conductive and stable at high temperature. Therefore it may be used as an insulating material of magnetic core.View full abstractDownload PDF (722K) -
Masazo Hanafusa, Rokuro Kawabata1957 Volume 21 Issue 1 Pages 35-39
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSome chemical,mechanical and microstructural experiments of lead and lead antimony alloys as the materials for the apparatus in the chemical industry, have been studied. (1) At temperature range of 50∼80°, the more antimony is contained in lead, the better H2SO4 resistivity is shown. (2) On account of containing Te and Cu, the flash point of lead-rich alloys rises, but contaning Bi, Zn, Sn and Sb it is lowered. (3) As the lamella β phase are made in grain structure, the tensile strength of the rolled lead is lower than the one casted having both the same content of Pb-Sb alloy. (4) The present authors have explained the relation between the microstructure and the flash point, on lead and lead rich alloys.View full abstractDownload PDF (1062K) -
Yoshichika Ôto, Takanobu Hamaguchi, Chujo Matsumoto, Taira Yoshi ...1957 Volume 21 Issue 1 Pages 39-43
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe direct-reading spectrochemical method using A.R.L. Industrial Research Quantometer with high precision source are available for the analysis of all metallic elements contained in aluminum and aluminum alloys. Two types of discharge are utilized, one spark-like to provide high precision for the higher content constituents, the other the arc-like to provide adequate sensitivity for the lower content constituents. This method is satisfactory in precision for all metallic elements and the standard deviation lies in the order of 2∼5%. Generally speaking, it would be preferable to supplement various additional standard specimens if maximum accuracy is required at all compositions. To overcome the matrix effects as much as possible, several sets of standard specimens must be prepared which contain the extraneous elements additionally, due to the fact that the extraneous elements in alloys affect the determination of working curves Experience with this new method described in the following report has been very useful in industrial determination.View full abstractDownload PDF (583K) -
Yoshichika Ôto, Takanobu Hamaguchi, Chujo Matsumoto, Taira Yoshi ...1957 Volume 21 Issue 1 Pages 43-46
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThere are various classifications in Cu alloys, and this report includes ordinary brass, bronze and high tensile brass. The discussion was made on the analysis methods for Zn,Sn,Pb and Fe in brass and bronze, and Zn,Sn, Fe, Ni,Al and Mn in high tensile brass, using the industrial research Quantometer by arc-like condition; this resulted in exact and quick analysis for these materials as with iron, steel and aluminium alloy previously reported. We made standard samples which were analyzed chemically by 2 or 3 persons for exact data. In the case of Quantometer analysis of Cu alloy, some defficulties were considered on the correction for large difference of Cu content and of the back-ground. These were solved by preparing many standard samples of the same quality and content, and by selecting the spark condition. The results were:(1) Analysis could be made by standard deviation of 0.3 to 0.6% for Zn and 1 to 3% for other contents in Cu alloy. (2) The influence of forging on Pb in bronze and brass could not be neglected.View full abstractDownload PDF (652K) -
Tomo-o Sato, Taiji Nishizawa1957 Volume 21 Issue 1 Pages 47-50
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThermo-magnetic studies on cementite isolated from low alloy steels confirmed that the compositions of cementite are frequently heterogeneous. (1) In 0.61%, 1.08%Mn steel, tempered between 500 to 650°, the cementite particles randomly contained various amounts of Mn; 1∼3%Mn at 500°,1∼5.5%Mn at 550°,1.5∼6.2%Mn at 600°,and 4∼6.3%Mn at 650°, by 1 hr tempering. It is conceivable that the heterogeneous enrichment of Mn in cementite particles intemp tempering was caused by ununiform or structure-sensitive movement of Mn atoms in ferrite matrix. Similar appearance was recognized in cementite in tempered 1.13%C, 1.42%Cr steel. (2) Cr concentration in pro-eutectoid cementite was higher than in the pearlitic cementite. But, Mn concentration in pro-eutectoid cementite was lower than in pearlitic cementite. Generalizing these results, it is deduced that A1pt-raising elements (Cr,Mo,W,V,Ti etc) dissolve in pro-eutectoid cementite more than in pearlitic cementite. On the contrary, A1pt-lowering elements (Mn,Ni etc) dissolve in pearlitic cementite more than in pro-eutectoid cementite.View full abstractDownload PDF (663K) -
Sakae Takeuchi, Toshio Honma, Hideji Suzuki1957 Volume 21 Issue 1 Pages 51-55
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe difference of the two types of the martensite transformation, namely the “Schiebung” and “Umklapp” transformation in iron-nickel alloys of various compositions, was studied by microscopic observation of the transformation markings and the etched structure. It has been found that the “Umklapp” transformation usually takes place in alloys containing more than about 30 per cent nickel, and the “Schiebung” transformation usually in alloys with nickel content less than 30 per cent. In the “Schiebung” transformation the markings as well as the etched structure depend considerably upon the concentration of the alloys. In alloys containing less than 20 per cent nickel, many parallel striations cover areas of the surface and after etching, such striations disappear and each area containing a single set of striations appears as homogeneous, while the alloys containing 25∼30 per cent nickel reveal a Widemanstätten or needle-like structure. The habit plane in the “Schiebung” is close to {111}γ and to {259}γ in the “Umklapp” transformation.View full abstractDownload PDF (1209K) -
S. Sakui, K. Sato, Y. Sato, C. Ohkawa1957 Volume 21 Issue 1 Pages 55-59
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe results of impact tensile tests of aluminium single crystals were compared with those of polycrystalline aluminium which had been described in the first report. The elongation and the tensile strength at impact teste were 10∼40% larger than those under statical load. These differences varied according to the orientation of the test pieces. The test crystals which were annealed at 500° for 30 minutes after impact tensile tests showed finer recrystallized grain sizes than those elongated statically by the same amount.View full abstractDownload PDF (834K) -
Gunji Shinoda, Yoshitsugu Amano1957 Volume 21 Issue 1 Pages 59-62
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe anneal-hardening phenomena at the grain boundary region and the grain center of α-brass were investigated by means of hardness test and X-ray analysis. On a coarse-grained crystal (5 mm in diameter) of α-brass (26.5%Zn) which was compressed by 33%, a remarkable anneal-hardening effect was observed at the grain boundary region after annealing at 200° but not at the grain center. Also, in the case of lower concentration of Zn (Cu-10%Zn alloy), at the grain boundary region a slight anneal-hardening effect was observed but not at the grain center. The anneal-hardening of micro-crystalline α-brass (1.3×10−2 mm in diameter) which was compressed by 31% also appeared only in its grain boundary region. On X-ray analysis by means of Laue method and divergent X-ray method, the diffraction pattern from the grain boundary region of cold worked α-brass increased its diffuseness after annealing at about 200°. This diffuseness recovered after annealing at 260∼300°. The residual stress (measured by mean of double reflection method) of 29%Zn alloy single crystal (36% rolled) decreased abruptly when it was annealed at 110°, but the diffuseness of diffraction pattern was not affected. From the results of those experiments, we can conclude that the anneal-hardening phenomena in α-brass is a type of strain-ageing due to diffusion of Zn atoms which takes place at the grain boundary region mainly.View full abstractDownload PDF (719K) -
Gunji Shinoda, Yoshitsugu Amano1957 Volume 21 Issue 1 Pages 62-65
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe change of electric resistances due to annealing of cold-rolled α-brasses (36%Zn) and pure coppers of various grain size was measured. The resistance vs. anneal temperature curve of α-brasses (40% and 83% rolled) shows a two step falling. But that of pure coppers (40% rolled) shows only a one step falling. The falling part of the one step curve resembles the second step in α-brass and depends on the mechanical properties. The falling point of electric resistance of brass differs according to the grain size in case of medium reduction (40% rolled). Therefore,the first step of falling of the resistance in α-brass is the proper one for alloying element and corresponds to anneal-hardening. The decrease of electric resistance at the first step in α-brass are due to decrease of the number of vacancies which are released by diffusion of solute atoms from the trapping due to solute atoms, and a diffusion of solute atoms takes place in the grain boundary region more frequently than in the inner region in the case of medium reduction.View full abstractDownload PDF (461K) -
Hidehiro Goto, Kichinosuke Hirokawa1957 Volume 21 Issue 1 Pages 65-68
Published: 1957
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA method of spectrophotometric determination of lead in electrolytic manganese and ferromanganese by use of dithizone was investigated. Using ammonium citrate as a masking reagent for a large amount of manganese and potassium cyanide for other heavy metals, lead in electrolytic manganese was determind by dithizone extraction method without separation. But in the case of ferromanganese,lead in the sample solution was separated from iron and manganese by dithizone extraction, and then the lead dithizonate was shaken with dilute acid to transfer lead to the aqueous phase. After bringing the solution to the suitable pH by adding ammonium hydroxide, together with cyanide, the lead in the aqueous phase was determined with dithizone.View full abstractDownload PDF (663K)
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