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Volume 20, Issue 8
Displaying 1-17 of 17 articles from this issue
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Tadao Sano, Jiro Satake, Teizo Otani1956 Volume 20 Issue 8 Pages 413-417
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe cause leading to the improvement of properties in specimens of alloys and solid solutions subjected to the pretreatment of strain-tempering was studied, using samples of heat-treated 0.4% and 0.8% C-steel, and in correlation with it, the removal of the fibre structure and the relation between the fibre structure and the microscopic structure were also investigated. The results obtained were as follows: (1) Cold-rolled specimens show heterogenous microscopic structures in them accompanying fibre structure, causing defects in the specimens. (2) By strain-tempering under appropriate conditions, such a fibre structure can be removed and the microscopic structure of the specimen homogenized. (3) The effect of strain-tempering in removing the fibre structure seems to cause improvement of the mechanical and the physical properties of the specimens when heat-treated thereafter, over those subjected to heat-treatment alone. (4) Our discovery of such effects of strain-tempering has led us to devise a new method of heat-treatment.View full abstractDownload PDF (1137K) -
Waichi Ota1956 Volume 20 Issue 8 Pages 417-421
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe distribution of hardness in transverse and oblique sections of a cold rolled Armco iron and nickel was measured. The distribution curves showed a convex form up to some degrees of working. The effect of skin pass upon the distribution of hardners and the relationship between the distribution of hardness and residual stress were also studied.View full abstractDownload PDF (646K) -
Waichi Ota1956 Volume 20 Issue 8 Pages 421-424
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe relationship between the distribution of hardness and the occurence of crack at the edges of a cold-rolled plate were studied. The rolling structure of the plate differed from that of a drawn wire in respect of surface structure. The changes in distribution of hardness and structure of a material rolled through a groove, and the influences of cold-rolling and subsequent annealing upon the mechanical properties were also studied.View full abstractDownload PDF (887K) -
Tasaburo Nishioka1956 Volume 20 Issue 8 Pages 424-427
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn dieser Untersuchung nach der neu entworfenen Methode wurden verschiedene Stahldrähte in 10% HNO3 von Oberfläche gelöst, dann wurde die Veränderung der Länge festgestellt und hieraus wurde die Längsrest-spannung errechnet. Danach bei patentiertem Draht wurde nur geringe Spannung gemessen, aber bei gezogenem Draht wurde sehr hohe Spannung gemessen, wobei in Rand Zugspannung (Max. 46 kg/mm2) und in Kern Druckspannung (Max. 87 kg/mm2) vorlagen. Restspannungen in gezogenen Stahldrähten: (1) steigen bis Gesamtzugabnahme von 82% mit wachsender Gesamtzugabnahme und bleiben bei Abnahme über 82% unverändert, (2) nehmen mit grösser werdendem Düsen-winkel zu, (3) nehmen mit wachsendem Kohlenstoffgehalt zu, (4) sind in bleipatentiertem Draht grösser als in luftpatentiertem Drht, (5) bei gleicher Gesamtzugabnahme steigen mit zuneh-mender Abnahme je Zug, (6) bei Zugverformung nehmen mit zunehmender Zugbelastung ab, besonders bei Belastung über 95% stark ab, und (7) bei Anlassen nehmen mit wachsender Temperatur ab.View full abstractDownload PDF (690K) -
Masayoshi Tagaya, Imao Tamura1956 Volume 20 Issue 8 Pages 428-432
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA correlation chart by which it is capable to derive quenching severity, H, from the cooling curves with silver specimen which are readily measurable, were made out by establishing the relationship between the cooling curves with silver specimen and the results of quenching of steels based upon the data presented in our 9th and 10th reports. Thus, it becomes possible to obtain the H value of any coolants readily and the application of many available charts presented by Grossmann and others may be strongly promoted, and furthermore it can be said that reasonable working procedure of quenching way be readily planned.View full abstractDownload PDF (867K) -
Saburô Shimodaira, Yoshinobu Sawada1956 Volume 20 Issue 8 Pages 432-435
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe field and service tests of high chromium steels are being curried on at the electric power generation stations using acid river water in the North-Eastern District of Japan. Hydraulic turbines and other equipments are made of various stainless steels and its behaviour is tested. The results of the tests during these two years are as follows: (1) The steels containing 13% chromium, 0.1% carbon and 1 to 2% molybdenum, copper or titanium are excellent for acid river water. These alloys remained in passive state during two years. (2) The plain steel containing 13% chromium and 0.1% carbon is unstable to acid river water unless it is adequately heat-treated.View full abstractDownload PDF (579K) -
Takashi Ikeno1956 Volume 20 Issue 8 Pages 435-439
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of Fe or Si on the recrystallization phenomena of sheets, cold-rolled from slab ingots without hot-rolling, was investigated. The results obtained may be summarized as follows: (1) The form of compounds in ingots changes considerably by heating at 500°, in the case of 99.6% Al, i.e. long and slender compounds were cut into pieces and rounded off at the corners. In the case of 99.99% Al, by addition of Fe the grain boundary becomes clearer with the heating hours of the ingots but when Si only is added or Si coexists with Fe, a similar tendency takes place. (2) The recrystallized micrograin becomes coarser in size and its temperature higher with the heating hours of ingots in the former. On the otherhand, in the latter the recrystallization temperature becomes lower and the grain finer insize with the heating hours of ingots by addition of Fe. When Si is added or Si coexists with Fe, a similar phenomenon as the former takes place. (3) In 99.99% Al, when Si is added to specimens containing constant Fe and heating hours of ingots are so longer, the recrystallization temperature becomes higher and its grain finer in size.View full abstractDownload PDF (1384K) -
Yoshikazu Hosoi1956 Volume 20 Issue 8 Pages 439-443
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper, it is described the effect of annealing on the softening of pure Al extruded rods. Generally, ununiform softening takes place in extruded rods by annealing at 300°, but long time heating (90 min) gives uniform softening to rods extruded at 325° and not to those extruded at 525°. It is thought that this ununiform softening is due to the different ability of recrystallization in extruded rods which are worked in different degree, by the facts that the softening curves in section of rods by annealing resembles that of cold worked metals. It was observed that the softening temperature is higher in rods extruded at higher temperature and that of surrounding or corner part in the section is lower than that inside the rods extruded at the same temperature.View full abstractDownload PDF (735K) -
Yoshikazu Hosoi1956 Volume 20 Issue 8 Pages 443-446
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn this paper, the effect of extruding conditions, which are the billet length, the extruding velocity, the die angle and the reduction %, on the softening of pure Al extruded rods upon annealing is descibed. The results obtained are as follows: (1) When 99.995% Al rods were extruded at about 400° by the same reduction %, in short billets the softening temperature, probably the recrystallization temperature, is raised more than in long billets and the higher the extrusion rate, the faster the softening. (2) A large die angle and a low reduction % raise the temperature described above. (3) 99.85% Al rods extruded at relatively higher temperature (about 510°) are hardened by 400° annealing. This hardening is remarkable at the tail and the surrounding part of the section in rods extruded by relatively low reduction %. When the reduction rate is raised, the hardening becomes weakes and the annealing temperature is lowered.View full abstractDownload PDF (549K) -
Ôhiko Kammori1956 Volume 20 Issue 8 Pages 446-448
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAny method developed hitherto was not satisfactory in view of reproducibility for determining such small amounts of As as up to about 0.05%. So the author made some studies to get a rapid and accurate photometric method, and found the following procedure most suitable: Dissolve 0.5 g of the sample in 20 mL of HNO3 (1+1), add 7 mL of MnSO4 (5%) and about 100 mL of water, heat to boil, add 2 mL of KMnO4 (3%), continue to boil, and when MnO2 begins to separate, add 1 mL of KMnO4 (3%), and boil gently until all MnO4′ is decomposed. Filter the hot solution, wash well with hot water, place the paper above the original beaker, dissolve the MnO2 with 7 mL of hot H2SO4 (3N) and a few mL of H2O2 (3%), wash with hot water and boil off the excess of H2O2. Transfer the cooled solution to a separating funnel, add 8 mL of (NH4)2MoO4 (1%), dilute to about 50 mL with water and add 5 mL of amylalcohol. Shake vigorously about 50 times, draw off the lower layer into a 100 mL volumetric flask, add 6 mL of H2SO4 (3N), add 10 mL of N2H4·H2SO4 (1%) and dilute to the mark with water. Warm for 3 to 4 minutes in boiling water, cool immediately in cold water, and measure the absorbancy with a photoelectric photometer using a S66 filter (820 mμ). Si up to 4.2% and P up to 1% have no effects. The time required for the analysis is 25 to 35 minutes and 0.005 to 0.07% of As in iron, steel and iron ore can be determined with the reproducibility of ±0.001% by this method.View full abstractDownload PDF (485K) -
Shigeo Wakamatsu1956 Volume 20 Issue 8 Pages 449-452
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe standard method of analysis for nitrogen in steel involves time-consuming digestion of sample. The procedure described in this paper permits rapid determination with very simple apparatus and an easy dissolving operation. A sample weighing 5 grams is transferred into a 500 mL Erlenmeyer flask and is dissolved in 60 mL of hydrochloric acid (1 to 1). The flask and the content are (30%) is added, and then heated until the solution of the sample is complete. Ammonia is then distilled from this solution by the same procedure as in the standard method.
Analysing samples of carbon steel and low alloy steel, no instances have been found where the results obtained by this procedure differ from those obtained by more drastic treatment beyond experimental error.View full abstractDownload PDF (630K) -
Kazuo Tsuya1956 Volume 20 Issue 8 Pages 453-456
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe isothermal formation of bainite, the temperature dependence of the bainite reaction, the surface distortions due to the bainite formation, the lowering of Ms temperature due to the bainite transformation and the behaviour of bainite plates during the step quenching were studied by using a hot stage microscope. From these results, it is concluded that bainite is formed by a shear process governed by diffusion.View full abstractDownload PDF (779K) -
Kyuya Nagasaki1956 Volume 20 Issue 8 Pages 457-460
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSConsidering the process of Ar1 transformation in steel it is concluded that in an eutectoid or eutectic reaction the length of PS and SK on the eutectoid or eutectic line PSK in the phase diagram shown by atomic percentage has an important role in the process and that the “abnormal structure” appears in hyperalloys if PS<SK or vice versa. In this report (1) the above mentioned relations, which have been already confirmed in many alloys in author’s previous works, were also confirmed in alloys forming double equilibrium diagrams and (2) reference was made to the curious “abnormal structure” in Cu-Si alloys. In the “abnormal structure” in Cu-Si alloys primarily precipitated γ crystals are surrounded by a banded structure of α+κ, the so-called Widmanstätten α.View full abstractDownload PDF (885K) -
Shiguéo Oketani, Sigemaro Nagakura1956 Volume 20 Issue 8 Pages 460-465
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSLa cémentation des films minces de fer condensés sous vide, dans le courant de CO ou CO+H2, donne toujours l’oxyde au-dessous de 300°. Mais en couvrant des préparations avec du poudre fin de fer réduit, le carbure-ε hexagonal et le carbure-χ de Hägg se produisent facilement. (Procédé “poudre de fer”) Quand le film condensé sur le sel gemme à la température ambiante est cémenté au-dessous de 250°, le carbure-ε hexagonal, entre 250° et 350° le carbure-χ de Hägg et enfin au-dessus de 350° se produit le carbure-θ, la cémentite. Quand le film condensé à 500° qui donne partout des diagrammes monocristallins est cémente, il s’oxyde et ne se cémente pas au-dessous de 250° par le precédé “poudre de fer”. L’orientation entre les cristaux de fer et de carbure est trouvée: (00 ·1)_ε \varparallel(\bar1 01)_Fe-α, [11 ·0]_ε \varparallel[111]_Fe-α Les auteurs ont déjà montré que la transition ε→χ→θ est pour ainsi dire allotropique et ils donnent des résultats récents sur les distances réticulaires et les intensités des carbures-ε et-χ.View full abstractDownload PDF (860K) -
Sigemaro Nagakura1956 Volume 20 Issue 8 Pages 465-468
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThin films of iron carbides were heated in vacuo and their phase transition was studied. It was found that the carbides transform irreversibly as ε→χ→θ. Diffraction patterns of the carbides transformed by heating are not different from those of the carbides produced by cementation of iron films. High temperature electrton diffraction showed that the phase transition ε→χ takes place at 380∼400° and the transition χ→θ at about 550°. θ carbide decomposes gradually into iron and carbon by prolonged heating above 550°. Since any trace of precipitation of iron or carbon could not be observed in the patterns after the phase transition, it is presumed that the carbides transform with no composition change. The 380° Curie point of ε carbide found by Hofer et al. is the transition temperature of ε→χ. Measurement of the thermal change of axial ratio of ε carbide showed that the carbide has considerable anisotropy.View full abstractDownload PDF (866K) -
Namio Ohtani1956 Volume 20 Issue 8 Pages 468-472
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSApplying the results of statisco-thermodynamical theory on hydrogen absorption to hydrogen electrode reaction, the author expressed the heat of activation ΔH* of the alloys which do not form any hydride by the following formula: ΔH^* = f(ρ, T) - αz’ RT lnλ_H^g J_H (N_A/N+N_B/κN)+α(ψ_AH+χ_d/2) where λHg: the absolute activity of H atom in gas phase, JH: the partition function of H atom, ψAH: the interaction energy between A atom in alloy AB and H atom, κ: a term concerned with ψAH and ψBH. The variation of ΔH* in iron and copper alloys and the validity of the results of the previous reports were discussed from the formula above mentioned.View full abstractDownload PDF (711K) -
Isao Kushima, Tsuyoshi Amanuma1956 Volume 20 Issue 8 Pages 473-476
Published: 1956
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSystematic studies on the system of CuO-Fe2O3 with Cu-ferrite formed from oxide mixtures of various mol ratios were performed. The main results were as follows: (1) Cu-ferrite can dissolve excess Fe2O3 at high temperatures and the dissolved Fe2O3 is educed by annealing above 550°. (2) The magnetic properties of Cu-ferrite were studied for various compositions and heat treatments. (3) There are two kinds of Cu-ferrite one being of the spinel structure with the chemical formula (CuOFe2O3) the other being rhombohedral (Cu2OFe2O3). The latter is formed above 1100°. (4) The growth steps of the crystals were observed on the sintered surface of Cu-ferrite.View full abstractDownload PDF (963K)
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