著者
藤巻 裕彦 鷹合 徹也 佐野 一仁
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.13, no.4, pp.550-555, 1995-11-05 (Released:2009-06-12)
参考文献数
3
被引用文献数
2 3

Crimping mechanism between the stranded copper wires and brass terminals was investigated in terms of repulsion force acting on crimp terminations by way of the stranded wires. The repulsion force was estimated from the load-displacement curves recorded during the crimping process. We obtained the results as follows;(1) Repulsion forces, which were based on the elastic deformation of the strand composing wires, are observed between the stranded wires and crimp terminals.(2) The repulsion forces have a peak value at the compression ratio of 27% in the crimp terminations.(3) The suitable conditions of the contact resistance and the crimping strength are secured under the conditions of the peak value of the repulsion forces.
著者
児玉 真二 椙浦 一輝 中西 省太 坂井 大介 辻村 吉寛 田中 学 MURPHY Anthony B.
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.31, no.1, pp.80-87, 2013 (Released:2013-04-17)
参考文献数
11
被引用文献数
1 1

The influences of welding condition on the atmospheric nitrogen mixing into the arc plasma in helium GTA welding was analyzed by numerical simulations. In order to evaluate the effects of the convection flow and the diffusion on the nitrogen mixing phenomenon, the distributions of the Peclet number was used. Elongation of the electrode length has low impact on the decrease of shielding gas concentration because the convection flow becomes dominant in this area which indicates higher Peclet numbers. Meanwhile, the nitrogen diffusion increases in the plasma area with the temperature of about 10,000K, so that elongation of the arc length leads to a remarkable decrease of shielding gas concentration. Additionally, the impact of convection flow increases in the arc center area where high-velocity plasma jet exists, and the shielding gas concentration tends to rise owing to higher welding current in the condition of sufficient shielding gas flow rate.
著者
柴田 公博 岩瀬 孝邦 坂元 宏規 瀬渡 直樹 松縄 朗 Hobenard Hohenberger Mueller Matthias Dausinger Friedrich
出版者
社団法人溶接学会
雑誌
溶接学会論文集 : quarterly journal of the Japan Welding Society (ISSN:02884771)
巻号頁・発行日
vol.21, no.2, pp.204-212, 2003-05-05
被引用文献数
4

Welding of Al-Mg and Al-Mg-Si alloys was performed using twin spot beams formed with two Nd: YAG lasers for the purpose of reducing porosities and humping caused due to unstable phenomena of weld bead during welding of aluminum alloys. The relationship between the configuration of the twin spot beam and the quality of the weld beads was investigated using X-ray and high-speed camera observations of the keyhole shapes and weld beads. X-ray observation of the weld beads showed that beam distance had a strong influence on the amount of porosities. At a shorter beam distance, porosities were apt to occurred in the weld. The amount of porosities decreased with an increase of beam distance. Beam distance affects keyhole shapes. The amount of porosities was clearly related to the ratio of keyhole depth to keyhole opening. Larger keyhole opening and/or shallower keyhole depth, smaller amount of porosities caused by instability of the weld pool.
著者
堀野 正也 渡辺 啓司 玉橋 邦裕
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.15, no.1, pp.38-44, 1997-02-05 (Released:2009-12-10)
参考文献数
14

Au-Sn solder has relatively high reliability because of the higher corrosion resistance and high temperature strength compared with Pb-Sn solder. It is, however, difficult to form Au-Sn alloy solder layer in the wet plating process on bonding surfaces. In this study, Au-Sn solder is provided as laminated Au-Sn-Au plating formed in a wet process on thin metal plates. Ni plating is formed prior to laminated Au-Sn-Au plating in order to improve wettability of the solder. Soldering process for thin metal plates without flux is investigated at the view point of soldering conditions and outgassing from the solder. Experimental result shows that Au plating contains larger amount of gas compared with Ni or Sn plating and the gas causes the solder layer to form voids. Forming many small holes around the specimen surface, amount of voids can be reduced. Peeling test shows that the peel strength of bonded specimen is influenced by the residual Ni thickness on the bonding interface rather than the bonding time or bonding pressure.
著者
大木 基史 武藤 睦治 大原 稔 高橋 雅士 石橋 達弥
出版者
社団法人溶接学会
雑誌
溶接学会論文集 : quarterly journal of the Japan Welding Society (ISSN:02884771)
巻号頁・発行日
vol.16, no.3, pp.395-404, 1998-08-05
参考文献数
18
被引用文献数
8

Two kinds of thermal cycle tests with short (10 min) and long (23h) holding times were carried out to investigate thermal cycling damage characteristics and thermal barrier property of thermal barrier coatings (TBCs). Surface cracks vertical to the coating surface were nucleated due to thermal stress during both the thermal cycle tests. Holding time had no significant influence on the surface cracking behavior. On the other hand, holding time had a significant influence on the thermal barrier property, which was degraded with increasing total holding time. The degradation of thermal barrier property was caused by the decrease in porosity and hence by the increase in density of ceramic layer.
著者
川上 博士 鈴木 実平 藤原 正典 中嶋 純也
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.25, no.1, pp.24-30, 2007 (Released:2006-12-25)
参考文献数
17
被引用文献数
2

The possibility and the mechanical properties of Al/Cu dissimilar bonding with liquefaction by the reaction diffusion in air were investigated at the temperature range between the melting point of aluminum and the eutectic temperature of Al-Cu system equilibrium diagram. The surface of each specimen was prepared by a simple preprocessing with the polishing and the cleaning by acetone. The Al/Cu dissimilar joint could be obtained by this bonding process in air. The bonding pressure is an important factor for this bonding process. The increment of bonding temperature and the decrement of oxygen concentration of air also promote solid state diffusion at Al/Cu interface. All bonded specimens in this study were fractured by the brittle fracture mode like cleavage fracture. The phases observed mainly in fracture surface is θ phase. The tensile strength of specimen bonded in air is similar with that of specimen by the diffusion bonding in vacuum.
著者
菅 泰雄
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.2, no.4, pp.676-681, 1984-11-05 (Released:2009-12-10)
参考文献数
11

The effect of diffusible hydrogen on mechanical properties of underwater wet welded joints by gravity welding process is investigated. The 4 and 6 mm dia. coated electrodes of five types and SM41 steel base metals of 6 and 9 mm in thickness are used.Main results obtained are summarized as follows;(1) The volume of diffusible hydrogen in underwater weld is much more than that in air weld. HD of underwater weld.increases with increasing of weld heat input and welding current and with an decreasing of thickness of base metal. However, HW shows roughly a constant value regardless of welding current and thickness of base metal.(2) The mechanical properties of the underwater weld, that is, tensile strength, elongation, bending ductility and notch toughness, can be improved remarkably by post weld heat treatment.(3) The evolution process of hydrogen from bead and butt weld and the recovery process of the mechanical properties of welds are able to be analysed by using the one-dimensional weld model. Consequently it becomes clear that the time factor r=Dt/l02, by which the great part of diffusible hydrogen diffuses out of weld, should be selected as the condition of post weld heat treatment.
著者
大沢 直樹 澤村 淳司 池上 祐一 山口 和恵
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.31, no.2, pp.141-156, 2013 (Released:2013-07-23)
参考文献数
18
被引用文献数
2 2

Plate temperature and heat input in oxyfuel gas cutting process with H2/LP gas and LPG flame are calculated by 3-dimensional FE heat conduction analyses. FE analyses are performed by using moving coordinates, and cutting groove temperature is determined by iterative calculation. The 2-dimensional groove temperature distribution determined by Matsuyama's theory is chosen as the initial values in this iterative calculation. The heat transfer properties of the preheating flame are determined by using the GA-based heat transfer estimation technique proposed in the previous report. The validity of the proposed numerical procedure and the accuracy of the determined groove temperature are examined by comparing the calculated and measured plate temperature and HAZ sizes. Heat input due to preheating, qG, and that due to self burning of steel, qB, are estimated in these analyses, and they are compared with the heat inputs estimated by Wells' and modified Wells' equations. The relation between the heat transfer characteristics of the preheating gas flame and plate temperature distribution is examined, and the cutting performance improvement mechanisms of Hydrogen preheating are discussed. As results, followings are found: 1) The 3-dimensional groove temperature distribution can be calculated by performing the iterative analyses procedure proposed in this study; 2) The critical cutting speed can be estimated once the gas heat transfer parameters are known; 3) It is not appropriate to evaluate the magnitude of cutting thermal deformation only from the preheating gas's total calorific value; 4) Under the conditions chosen, the heat generated by self burning is inadequate to maintain the cutting process, and it is essential to supplement heat by preheating; 5) The faster cutting speed and smaller total heat input of H2/LP gas are results of the larger local heat transfer coefficient below the gas ejection hole. It is supposed that the improvement in oxyfuel gas cutting performance can be achieved by modifying the heating apparatus so that the local heat transfer coefficient becomes larger.
著者
服巻 孝 中村 満夫
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.10, no.3, pp.337-342, 1992-08-05 (Released:2009-06-12)
参考文献数
8
被引用文献数
1 1

Copper to copper lap joint was made by the resistance heating, applying pressure simultaneously. The copper plate was pre-soldered and the alloyed layer was pre-formed by using Pb-50Sn solder and then joint mechanism of press-soldered joints was analyzed.The reason of enhancing strength and heat resistance heated by applying voltage in press-soldered joints is summarized as follows.(1) Solder composition turns to Cu-Sn alloy composition.(2) Joint layer with higher melting point was formed in which Cu increases and Sn decreases.(3) In terms of the crystal structure, Cu3Sn, Cu6Sn5 and Cu(α) phases turns to Cu41Tn11 and Cu(α) phases which have high heat resistance.
著者
服巻 孝 中村 満夫
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.10, no.2, pp.228-233, 1992-05-05 (Released:2009-06-12)
参考文献数
7

Copper and some other materials were joined using the resistance heating apparatus by which heating and pressure could be applied simultaneously. The materials used were presoldered and the alloyed layer was formed on each of them by using Pb-Sn solder.Tensile test at the room temperature revealed that fracture of all specimens originated in copper material.The layers consisted mainly of Cu-Sn, Cu-Zn-Sn, Cu-Ni-Sn, Cu-Fe-Ni-Sn when copper, brass, nickel, and Fe-42Ni alloys were jointed with copper respectively.
著者
才田 一幸 藤本 哲哉 西本 和俊
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.28, no.2, pp.216-221, 2010 (Released:2010-07-21)
参考文献数
19
被引用文献数
5 5

In order to clarify the behaviour and mechanism of the hydrogen embrittlement in SUS304ULC/Ta/Zr explosive bonded joint, the hydrogen embrittlement cracking at Ta/Zr bond interface was characterised. Cracks occurred in the Zr substrate along the wavy interface of the hydrogen-charged Ta/Zr joint. The cracking susceptibility increased drastically when the potential of specimen during hydrogen-charging was reduced below the redox potential of hydrogen. γ-ZrH and δ-ZrH were precipitated in the hydrogen-charged Zr and the precipitated γ-ZrH possessed a (0002)α-Zr//(11-1)γ-ZrH, [21-1-0]α-Zr//[110]γ-ZrH crystallographic relationship. An in-situ observation of the hydrogen embrittlement cracking with SEM and TEM revealed that cracks were initiated in zirconium hydrides and propagated preferentially along zirconium hydrides. These results suggested that the hydrogen embrittlement mechanism of the Zr base metal was caused by the precipitation of zirconium hydrides and the brittle fracture of them.
著者
進藤 裕英 高橋 知貴 堀口 勝三 小堀 智之 真田 和昭
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.15, no.2, pp.370-375, 1997-05-05 (Released:2009-06-12)
参考文献数
10
被引用文献数
2 1

JJ1 type austenitic stainless steel is emerging as the preferred structural material for superconducting magnet casings to operate at liquid helium temperature (4K). In order to evaluate the cryogenic fracture toughness and the temperature rise of tangsten inertgas (TIG) weld in 200 mm thick forged JJ1 type austenitic stainless steel plate for fusion reactor magnets of the next generation, elastic-plastic fracture toughness (JIC) tests were performed with 1T compact tension specimens at 4K. Testing was conducted in accordance with ASTM standards E813-87 for determining JIC using the unloading compliance technique to monitor crack growth. Au/0.07% Fe -Chromel thermocouples were used to measure the temperature rise near the crack tip. The effects of specimen location and nitrogen content on JIC are examined. Specimens were subjected to scanning electron microscopy (SEM) after fracture testing. The effect of inclusion content on the elastic-plastic fracture toughness parameters (JQ, JIC) is also discussed using optical microscopy and energy dispersive X-ray spectrometer (EDX).
著者
鈴村 暁男 山崎 敬久 高橋 邦夫 恩澤 忠男
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.13, no.1, pp.39-45, 1995 (Released:2009-06-12)
参考文献数
3
被引用文献数
1 1

In the brazed joint of natural diamond to Fe-42 Ni alloy made with Ag-Cu eutectic filler including 4.5 wt% Ti, the behavior of titanium segregation changes according to the brazing thermal cycles, which causes the change in joint strength and the fracture mode. The chemical reaction products of diamond and the filler were identified by ESCA and EDS analyses on the fractured surfaces at the brazed interface, where the analyzed surfaces were made using a developed tensile shear test method, in order to propose the model of formation mechanism of the joint structure.The analytical results revealed that such a structure as consists of TiC nucleation surrounded by Ag and/or Cu is preferred as the joint structure. It was also indicated that the segregation of Ti at the joint interface reduces the bonding strength, where the fracture is liable to occur at the interfaces of diamond-Ti and/or TiC-Ti.The relation between the joint structure and the strength was also discussed using the disregistry values calculated in the previous report. The structure formation models of the interface between diamond and brazing filler metals were proposed to explain the change in the structure and strength of the joint made by different cooling rates.
著者
小野 守章 海津 享 真保 幸雄 樺澤 真事 佐藤 章仁 戸塚 和弘 中村 真一郎 玉田 健二
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.14, no.4, pp.660-665, 1996-11-05 (Released:2009-12-10)
参考文献数
9
被引用文献数
1

New laser carburizing quench process using hydrocarbon gas as the assist gas was proposed to strengthen ultra low carbon steel sheet.In this paper, the effect of CH4 concentration and various laser radiation parameters on hardness and area of fusion zone was investigated. Tensile strength of laser treated specimen were measured. The results of the present work were summarized as follows, (1) By using CH4, fusion zone with vickers hardness of more than 400 was obtained.(2) Hardness and area of fusion zone were well controlled by CH4 concentration, laser power, focal position, beam scanning rate and so on.(3) Tensile strength of laser treated specimen was about 20% higher than that of base metal.(4) CO2 laser carburizing apparatus consisting of the nozzle head and the exhaust of CH4 was newly developed, which enabled to strengthen ultra low carbon steel without breaking focal lens and the combustion of CH4.
著者
野村 和史 山下 隼 井村 文哉 浅井 知
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.36, no.4, pp.264-273, 2018 (Released:2018-11-15)
参考文献数
28
被引用文献数
2

This study proposed the estimation method of the depth of wed penetration using the experimental measurement of the weld pool shape and the temperature on the front surface during the welding. This method is based on the simple heat conduction calculation, and does not require a flow-field calculation and a heat input information as seen in various welding simulations. In this paper, we first examined the applicability of this method to a bead on plate welding. As a result of application to TIG and A-TIG welding with SUS304 base metal, we obtained the estimated depth with an error of +14∼30% to the actual depth. We investigated this experimental result by the analytical heat conduction model, and found that utilizing the surface temperature with wider area has a possibility to estimate the depth with higher precision.
著者
権田 英修 白井 康宏 大橋 修 安井 利明 福本 昌宏
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.29, no.4, pp.358-363, 2011 (Released:2012-01-18)
参考文献数
12
被引用文献数
1 1

Generally, cemented carbides (WC-Co) that consist of tungsten carbides and cobalt are used for cutting tools. But since cemented carbides are made of import dependent rare metal, reuse and recycling are required. If cylindrical shanks that the cutting edges are cut off can be combined, it is possible to reuse those shanks as new cutting tools. But in this case, the joining strength of brazing method tends to be rather weak for being used as cutting tools. Instead of the brazing method, the diffusion bonding will be expected with the high strength and the small deformation. Many studies on the diffusion bonding were reported, but there were few studies on the diffusion bonding of cemented carbides.In this study, a potential for applying the diffusion bonding of carbides was investigated. So the effect of the bonding condition on the bending strength, the microstructure of the bonding line and the distribution of tungsten and cobalt were examined. As a result, the strength of the diffusion bonding was higher than that of the brazing at higher than 1100°C, and at 1200°C, it was almost the same as the base metal's strength. Cemented carbides were successfully joined by the diffusion bonding.
著者
植松 美彦 戸梶 惠郎 戸崎 康成 柴田 英明
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.27, no.4, pp.261-269, 2009 (Released:2009-10-23)
参考文献数
16
被引用文献数
4 7

Fatigue tests were conducted under fully reversed axial loading (R = -1) in laboratory air and 3% NaCl solution using friction stir welded (FSW) joints of 7075-T6 aluminium alloy sheets. The FSW joint exhibited lower tensile strength than the parent metal. Heat input during FSW process re-dissolved strengthening precipitates, resulting in softening in the weld zone and lower tensile strength. In laboratory air, the fatigue strength of the FSW joint was comparable to that of the parent metal, which could be attributed to grain refinement in the stir zone (SZ) and dynamic aging during fatigue loading in the softened weld zone. In 3% NaCl solution, the fatigue strength of the FSW joint was lower than that of the parent metal. Corrosion pits were preferentially formed at the boundary between thermo-mechanically affected zone (TMAZ) and heat affected zone (HAZ), which led to premature crack initiation in the FSW joint. Such predominant formation of corrosion pits was due to the sensitization caused by heat history during FSW process.
著者
川上 博士 西河 厚志 吉村 幸治 駒田 将樹 鈴木 実平
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.35, no.1, pp.21-28, 2017
被引用文献数
1

The properties of rotating tool spot joining joints with different rotating tools by the combination between the shoulder diameter and the probe length were investigated in this study. The shoulder diameter of rotating tool affects the tensile strength of the joint significantly. An oversize shoulder diameter decreased the joint strength. The probe length affects more the fracture mode than the joint strength. Interface fracture mode occurred with a rotating tool of short probe length. Plug fracture occurred with a rotating tool of long probe length. Rotary motion of restricted area in the joining interface by the rotating tool was confirmed by displacements of the joining interfaces. Rankin vortex was observed on the joining interface by velocity distribution of rotary motion of joining interface. Al oxide film layers were formed spirally on upper joining interfaces
著者
西本 和俊 才田 一幸 鳥居 尚之 大重 広明
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.21, no.2, pp.256-266, 2003 (Released:2004-08-31)
参考文献数
14
被引用文献数
1 3

Monte Carlo simulation of grain growth and recrystallization behaviors in HAZ was carried out for GTA and LB weldments of carbon steel and nickel on the basis of the Potts model. The temperature distribution in HAZ was analytically computed by quasi-stationary heat conduction equations. The coarsening of grain in HAZ increased markedly in the vicinity of fusion boundary in the GTA weldments compared with LB weldments of carbon steel. The recrystallized zone spread over the HAZ along the fusion boundary in GTA and LB weldments of nickel. The recrystallized grains near the fusion boundary were also coarsened with increasing the heat input while the grains around the interface between recrystallized and un-recrystallized zones were refined. It was elucidated that the grain growth and recrystallization behaviors in HAZ could be well visualized by the Monte Carlo simulation.
著者
大村 悦二 野村 和史 宮本 勇
出版者
一般社団法人 溶接学会
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.21, no.3, pp.344-349, 2003 (Released:2004-11-16)
参考文献数
5

In recent years, applications of solid-state lasers with frequency conversion techniques such as SHG, THG and FHG to precision microfabrication progress rapidly. When nonlinear optical crystal used for frequency conversion absorbs laser beam, temperature of the crystal rises, and the frequency-conversion efficiency decreases. In this study, KH2PO4, that is potassium dihydrogen phosphate (KDP), whose physical properties are well known was supposed as a nonlinear optical crystal for SHG. Temperature dependence of frequency-conversion efficiency was examined theoretically by solving the coupling problem composed of heat conduction equation and complex amplitude equations, which are derived considering the absorption of laser in the crystal. The temperature change of the crystal induced by Nd:YAG laser absorption, the local change of refractive indices, and the consequential variation of SHG frequency-conversion efficiency were analyzed for single and repetitive pulses. As a result, the temperature dependence of frequency-conversion became clear quantitatively. Remarkable inverse-conversion of SHG also appears for the repeated laser irradiation with high power density.