巻号一覧
46 巻, 9 号
選択された号の論文の15件中1～15を表示しています
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R. Weck1977 年 46 巻 9 号 p. 613-615
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーPDF形式でダウンロード (237K) -
切断溝の形成現象西口 公之, 松山 欽一1977 年 46 巻 9 号 p. 616-622
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe kerf formation in a plasma arc cutting is influenced by the behavior of molten metal within the cutting groove in addition to the heat distribution on the cutting front described in the report 2, as well as known in welding bead formation. So, the authors deduced the kerf formation mechanism by the investigations of heat input character and molten metal flow pattern from analysis of the cutting front shapes and the traces of insert metal flow, respectively.
The heat distribution within the groove in a palsma arc cutting can be roughly approximated to that in a plasma jet cutting, in which heat flux from plasma stream to the cutting groove exponentially decreases along the center of cutting front in regardless of division into three regions I-III described in the report 2, since the most of energy given to the groove is generated in the constricted nozzle part within torch.
While, the molten metal within the groove indicates complex flow patterns in each region I-III contrary to the expectation from the plasma stream. In the region I and II, the molten metal flows toward side-and-downward due to surface tension in addition to the momentum of plasma stream. Especially, in the region II at straight polarity, the sideward metal flow is remarkable, since the most of anode spot locates on the center part of cutting front. The region III is divided into two parts from the difference in flow pattern. In the upper part of III (region III-a), the molten metal flows along or slightly toward the cutting front. In the lower part of in (region III-b), the molten metal strongly flows toward sideward, too, because of the momentum change of the stream due to change inclination of cutting front.
Such metal flows toward and in sideward act to spreading the kerf width, so that the kerf width in the region II is wider than that in the region I or III-a, and lower part widening kerf is formed in the region III-b. The kerf spreading phenomenon in the region I is suppressed by using the reverse polarity torch, since the cathode spot wanders near and on the soldification line (drag line).抄録全体を表示PDF形式でダウンロード (7542K) -
桐原 誠信, 小沼 勉, 渡辺 潔1977 年 46 巻 9 号 p. 623-627
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーWith the demand for the increasingly large capacity of machines and equipment, structural dimensions are growing large, and design stress is becoming higher eventually. This naturally necessitates the use of high-strength steel possessing high tensile and high toughness.
Although mild steel is generally adopted for welded structures, it needs an exceedingly large gauge to give sufficient strength and involves difficulites in building up welded structures.
The specimens adopted in this research were multilayer welded joints of 80 kg/mm2 high-strength steel welded by submerged arc welding or manual arc welding. Under the practical welding process, the relationship between the restraint stress that acts in the rectangular direction of welds and the crack was sought, and critical restraining stress for crack initiation was obtained. Similar experiments were conducted with smaller specimens as well.抄録全体を表示PDF形式でダウンロード (2850K) -
希土類元素の添加によるナイフラインアタック感受性の改善井川 博, 中尾 嘉邦, 西本 和俊, 中浜 修平, 井上 倫人1977 年 46 巻 9 号 p. 628-635
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe mechanism of knife line attack phenomena in SUS 321 and SUS 347 were already investigated in detail up to this report.
In this report, effects of addition of rare earth metals (REM) on the improvement of knife line attack sensitivities in SUS 321 and SUS 347 were studied based on the results obtained in the previous reports. At the same time, the mechanical properties and the corrosion resistances of REM bearing SUS 321 and SUS 347 were examined.
The results obtained in this reports are as follows;
1) The knife line attack sensitivities of SUS 321 and SUS 347 were improved by addition of REM. The optimum quantities of REM were about 0.15% in SUS 321 and about 0.11% in SUS 347.
2) By addition of REM, the quantities of M23C6 precipitated in HAZ of both SUS 321 and SUS 347 decreased.
This fact was considered to be the cause of improvement of knife line attack sensitivities in these steels.
3) Tensile properties at elevated temperature of REM bearing steels were almost same as ones in basesteels, and corrosion resistances of REM bearing steels were slightly improved.抄録全体を表示PDF形式でダウンロード (6185K) -
溶接熱影響部の結晶粒径分布式井川 博, 大重 広明, 野井 伸悟, 伊達 洋彦, 内川 啓1977 年 46 巻 9 号 p. 636-641
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーIn this report, the equation representing grain size in weld-heat affected zone (HAZ) of two-dimensional bead was derived using grain growth equation and heat conduction equation.
Furthermore, relation between heat input and grain size in HAZ was clarified using the equation obtained above.
Main results obtained are as follows.
(1) Grain size in HAZ is represented by Eq. (13) for commercial-purity nickel and by Eq.(14) for steels used.
(2) Maximum value for austenite grain size in HAZ of steels used is proportional to the square root of heat input.
(3) Coarse grain zone in HAZ of steels used can be estimated using Eq.(17) or Eq.(18).抄録全体を表示PDF形式でダウンロード (372K) -
電子ビームのエネルギー密度入江 宏定, 橋本 達哉, 稲垣 道夫1977 年 46 巻 9 号 p. 642-648
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーIt was shown in the reports already published that energy density was the most responsible parameter to penetration depth in electron beam welding. Up to date, there have been proposed various measurements of the density. Most of these, however, used a method, in which a rod or a plane cuts the beam rapidly and variation of beam current is measured so that density distribution obtained is in X or Y direction.
The authors developed a new apparatus able to measure current density distribution in raidal direction and carried out various experiments.
The results are summerized as follows;
1) The electron beam shows various types of density distribution along the objective distance.
2) Focal point or convergence angle of the electron beam always fluctuates according to ripple component of electron beam power source.
3) In comparison between the results by this apparatus and by the "AB-test" proposed by Dr. Arata et al, the AB-test is one of useful methods when the energy density of electron beam is sufficiently high.抄録全体を表示PDF形式でダウンロード (1382K) -
アーク現象およびビード形状に与える水圧の影響荒田 吉明, 浜崎 正信, 榊原 実雄1977 年 46 巻 9 号 p. 648-655
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe effect of water pressure on the MIG arc phenomena and bead shapes was studied in the high water pressure simulator. The results obtained are as follows.
1) Available shielding effect was obtained under high water pressure by the use of water curtain dual shielding method.
2) Bead width, penetration depth and reinforcement became narrow, deep and high respecively with increasing of water pressure under the constant welding condition, but in case of short circuiting arc, the increase of penetration was slight.
3) Critical welding current and arc voltage for stable spray transfer rised with increasing of water pressure.
4) Spatter free weld beads were obtained even in high pressure corresponding to water depth of 90 m selecting the proper welding condition.
5) Oxygen addition to argon shielding gas brought the stable spray transfer and remarkable increase of bead width and penetration especially in high water pressure.抄録全体を表示PDF形式でダウンロード (6488K) -
靭性におよぼす母材成分元素の影響山口 哲夫, 平 忠明, 平林 清照1977 年 46 巻 9 号 p. 656-659
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe effects of the chemical composition of base metal on the toughness, hardness and microstructure of weld metal was studied in order to get higher toughness of submerged arc weld metal of high grade line pipes produced from controlled rolling process. As a result the authors clalified the optimum micro-alloy content of base metal which would make the high toughness weld metal.
(1) Low C-0.2 Si-1.6 Mn system of base metal was the best material for toughness of weld metal. Microalloy element should be added to this basic composition to make high toughness weld metal.
(2) Combined addition of nickel and molybdenum was best as micro-alloy element. Copper and Chromium was effective if a small amount.
(3) The reason was due to preventing proeutectoid ferrites of weld metal and making them fine.抄録全体を表示PDF形式でダウンロード (1461K) -
圓城 敏男, 大内 光男, 那須 三郎, 池内 建二, 荒田 吉明1977 年 46 巻 9 号 p. 660-665
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーDiffusion welding between pure molybdenum and heat-resisting alloy hastelloy X has been performed in vacuum at the temperature range of 750°C-1200°C. Tensile strength of the weld joint at room temperature is discussed on the effects of methods in welding technique and a use of Ni insert-metal. The use of two steps welding technique and a Ni insert-metal is appreciable to improve the tensile strength of weld joint, but the fracture had occured always near weld bond.
Metallographical investigations using transmission electron microscopy (TEM), scanning electron miccroscopy (SEM), X-ray diffraction analysis and electron probe X-ray microanalysis have been performed in order to clarify the effects of two steps welding technique and a use of Ni insert-metal on the microstructure near the bonding interface. Results obtained are summarized as follows;
(1) Two steps welding technique including a short time annealing at high temperature (1 minute at 1200°C) increases the real metal-contact between molybdenum and hastelloy X, and takes the improvement of the joint strength. Furthermore, this technique is useful not to enlarge the deformation by welding procedure.
(2) Application of the Ni insert-metal suppresses the formation of the brittle intermetallic compound, P phase, and increases the tensile strength. However the formation of binary compound, δ-MoNi, was observed at the bonding interface.
(3) Fracture of the weld joints by the tensile strength tests has occured always through the intermetallic compounds and also along the grain boundaries of molybdenum base metal.
(4) After the welding procedure, the voids and MoO2 were found out at the grain boundaries of molybdenum using SEM and TEM techniques.抄録全体を表示PDF形式でダウンロード (3403K) -
益本 功, 篠田 剛1977 年 46 巻 9 号 p. 665-670
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーElectrosalg welding process for aluminum seems to be favarable to prevent the proosity in weld metal because of its small solidification rate. However, electrosalg welding process of aluminum needs the higher welding current than that of steel to prevent the lack of fusion.
This report describes a vertical welding process of aluminum by halfsubmerged arc, which can reduce lack of fusion with lower welding current compared with electroslag welding. The influence of welding conditions on the lack of fusion and porosity in weld metal using the consumable nozzle and graphite shoe is also reported and the following results are obtained;
1) Vertical welding process by half-submerged arc gives sound weld metal and no lack of fusion using electrode wires 2.4 mm and 3.2 mm in dia. with 900-1200 A welding current and 0.1-0.5 of flux ratio.
2) The suitable flux composition is NaCl 20 %-KCl 40 %-Na3AlF6 10 %-LiCl 30 %.抄録全体を表示PDF形式でダウンロード (4314K) -
電極形状および板厚が溶接現象に及ぼす影響山本 利雄, 奥田 滝夫1977 年 46 巻 9 号 p. 671-678
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe influences of shape and dimensions of electrodes on the weldable current range and effects of plate thickness on welding phenomena are studied. The results obtained are as follows.
Weldable current range ΔIa/Iav increases with increased ratio of electrode face width W as against the plate thickness t and with increased P/W. The proper face width and electrode force for various thicknesses can be dicided by the equation W/t=6 and P/W=130kg/mm. Improvement of ΔIa/Iav can be achieved by R type electrodes especially in case of thicker plate thickness as well as efficient electrode force. ΔI/aIav is affected little by the outer diameter of electrode over a range from 280 to 400 mm in diameter. ΔIa/Iav for given welding speed decreases as plate thickness increasees except for welding speed in which the upper limit of welding current is restricted by electrode sticking. The type of weld formation process of other plate thickness can also divided into two types with welding speed. The transition welding speed becomes lower for thicker plate and the melting efficiency is saturated or becomes the maximum value at the transition welding speed.抄録全体を表示PDF形式でダウンロード (4875K) -
自動圧接実験結果高野 重雄, 横川 孝男, 池野 輝夫1977 年 46 巻 9 号 p. 679-686
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーThe authors developed a new system of automatic gas pressure welding to improve the quality and reliability of gas pressure welds, and reported on the system and apparatus in the preceding paper (Part 1). The present paper is to relate the results of welding experiments to settle proper conditions for automatic welding, that is, the process of welding, influences of welding conditions as well as properties of automatically welded joints. The materials used in this experiment are the largest deformed bars specified in JIS (51 m/m dia.).
Joints by this automatic gas pressure wleding showed satisfactory properties and assured the feasibility and reliability of this system.抄録全体を表示PDF形式でダウンロード (7862K) -
溶接姿勢と溶込み現象荒田 吉明, 富江 通雄1977 年 46 巻 9 号 p. 686-693
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーNew type powerful "deflector" for high power electron beam is developed and "deflection beam" inclined at any angle to "vertical beam" can be easily obtained.
By using this "deflection beam", all position electron beam welding can be developed. Especialy such rectangular deflection beam, "horizontal beam", is actually applied for vertical and horizontal position welding and it is promissing of making high grade bead with deep penetration.抄録全体を表示PDF形式でダウンロード (4406K) -
菊田 米男, 落合 真一郎, 大杉 卓生, 平山 朝朗1977 年 46 巻 9 号 p. 694-701
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーIt is known that fracture toughness value changes, within the same material, depending on the ambient temperature and loading rate used for testing. For some material, fracture toughness value obtained at rapid loading rate is considerably lower than the one by static case. Thus the former value has more critical meaning on fracture mechanics standpoint.
We have succeeded for the first time to measure dynamic fracture toughness K(T, K) behaviours by using calibrated piezo-electric transducer for load detection. The signal is amplified by charge amplifier, and is recorded by digital memory. SM 50 steel was chosen for the present investigation because of its expectedly strong loading rate dependence of fracture toughness value. For dynamic testing, extraneous signals due to inertial loading and specimen vibrations were circumvented by lowering initial tup velocity.
K(T, K) was measured at the temperature range between -196°C and room temperature. Strong loading rate dependence was found for simulated H.A.Z. and base metal. On the other hand, simulated weld-bond, which has poor toughness at slow bend test, has small dependence of fracture toughness value on loading rate. The difference in the dependences is very clear at higher temperature range, and they both become less sensitive to loading rate as temperature decreases toward -196°C where the loading rate dependence essentially disappears. Furthermore, temperature dependence of fracture toughness value was found to be large for simulated H.A.Z. and base metal while the dependence is much less for simulated weld-bond.抄録全体を表示PDF形式でダウンロード (559K) -
西田 隆法, 宮本 栄, 三上 博1977 年 46 巻 9 号 p. 701-706
発行日: 1977/09/05
公開日: 2011/08/05
ジャーナル フリーIt is said that fume produced during arc welding is harmful for human body, but there has been no simple and easy method to measure fume density in welding shop.
An experiment was performed in order to obtain the relationship between filter paper method which is direct measuring method and indication of digital dust indicator which is indirect measuring method.
The, results of the experiment are as follows:
(1) There is a constant relationship between value of fume density obtained by filter paper method and indication of digital dust indicator.
(2) It is possible to obtain the same accurate value of welding fume density as that to be obtained by filter paper method by multiplying, by the'correction factor 2, the corresponding value measured with digital dust indicator of welding fume, produced from either the electrode or the weldment.
(3) The indication of digital dust indicator is not affected by difference between reflections of fumes.
(4) The digital dust indicator is suitable as a simple and easy measuring method in welding shop.抄録全体を表示PDF形式でダウンロード (2736K)
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