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
3

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
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 2

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

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 6

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.
著者
永塚 公彬 田中 宏宜 肖 伯律 土谷 敦岐 中田 一博
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.33, no.4, pp.317-325, 2015 (Released:2015-11-19)
参考文献数
37
被引用文献数
6 14

Dissimilar materials joining of an A5052 plate and a carbon fiber reinforced thermoplastic (CFRTP), which consisted of polyamide 6 (PA6) with 20 wt% carbon fiber addition, was performed using friction lap joining (FLJ) with the Al alloy plate as a top and the CFRTP plate as a bottom. The joint characteristics were evaluated to investigate effects of the surface treatment by the silane coupling treatment for A5052 and the joining speed on the joining properties. The joint strength was increased by inducing the silane coupling treatment for the A5052 plate surface. The tensile shear fracture load of the silane coupling treated FLJ joint increased with increasing the joining speed up to 6.67mm/s, and then decreased. The maximum tensile shear fracture load of 5.0kN was obtained at the joining speed of 6.67mm/s, and the fracture occurred at the CFRTP base plate with the joint efficiency of 97%. The shear strength of the joint interface of the joint formed at the joining speed of 1.67mm/s, which fractured at the joining interface by the tensile shear test, was estimated about 19MPa. The covalent bondings between the A5052 plate and the silane coupling layer, and the silane coupling layer and the CFRTP plate were indicated by inducing the silane coupling treatment.
著者
前中 浩 佐久間 正明 松岡 一祥
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.4, no.1, pp.95-101, 1986-02-05

The stress relief phenomena in pre-loading on butt welded plates and the changes of material properties owing to the pre-loading were investigated theoretically and experimentally. A over-matching welded joint composed of a 50 kgf/mm^2 class weld metal by automatic CO_2 welding and a mild steel of 16 mm thickness was tested. The strain distributions measured by strain gages showed the same tendency to those calculated by FEM, under pre-loadings in directions perpendicular and parallel to the weld line. The perpendicular loading was superior to the parallel loading in terms of reducing the plastic strains caused of the stress releaving. Strain aging embrittlement of weld metal, HAZ and base metal obtained by 2 mm V notched Charpy test was quite proportional to prestrain, and significant difference among them could not be found. The equations for estimation of the brittle fracture initiation temperature were checked. The rise in the temperature caused by the pre-loading was less than that due to the weld residual stress. It was concluded that the effective pre-loading method recommended in the present paper was sufficiently safe.
著者
宇田川 誠 勝山 仁哉 西川 弘之 鬼沢 邦雄
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.28, no.3, pp.261-271, 2010 (Released:2010-07-29)
参考文献数
19
被引用文献数
2

Austenitic stainless steel is welded as a cladding on the inner surface of a reactor pressure vessel (RPV) made of low alloy steel. In order to assess the structural integrity of the RPV precisely, the residual stress distribution caused by weld-overlay cladding and post-weld heat treatment (PWHT) is evaluated. Since the cladding layer is very thin compared to vessel wall, it is necessary to evaluate the residual stress distribution around the weld fusion line can be very steep. In this study, cladded specimens were fabricated using different welding methods. Residual stress measurements using both sectioning and deep hole drilling (DHD) methods were then performed to evaluate the residual stress distributions through the weld fusion line. Three-dimensional thermal-elastic-plastic-creep analyses based on finite element method were also conducted to evaluate the residual stress caused by weld-overlay cladding and PWHT. It was shown that analytical results provided reasonable agreements on weld residual stress with experimental results. It was also clarified that the main cause of residual stress due to welding and PWHT was the difference of thermal expansion between weld and base metals.
著者
寺崎 俊夫 福田 貴生 北村 貴典 増本 展祥
出版者
JAPAN WELDING SOCIETY
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.19, no.3, pp.564-569, 2001

This paper deals with a fatigue strength of corner joint without backing plate using experimental data and numerical method. A lack of penetration is usually found at the root of the corner joint. The fatigue strength generally depends on the lack of penetration. From comparing between experimental data of fatigue strength and numerical results, it is shown that a stress intensity factor is useful for predicting the fatigue strength of the corner joint. The stress intensity factor is calculated under condition with changing main factors of corner joint. It is suggested that the plate thickness and the length of lack of penetration are main factors of the fatigue strength of the corner joint.

1 0 0 0 OA 正誤表

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.1, no.2, pp.242-242, 1983 (Released:2009-12-10)
著者
前中 浩 佐久間 正明 松岡 一祥
出版者
JAPAN WELDING SOCIETY
雑誌
溶接学会論文集 (ISSN:02884771)
巻号頁・発行日
vol.4, no.1, pp.95-101, 1986

The stress relief phenomena in pre-loading on butt welded plates and the changes of material properties owing to the pre-loading were investigated theoretically and experimentally. A over-matching welded joint composed of a 50kgf/mm<SUP>2</SUP> class weld metal by automatic CO<SUB>2</SUB> welding and a mild steel of 16 mm thickness was tested.<BR>The strain distributions measured by strain gages showed the same tendency to those calculated by FEM, under pre-loadings in directions perpendicular and parallel to the weld line. The perpendicular loading was superior to the parallel loading in terms of reducing the plastic strains caused of the stress releaving.<BR>Strain aging embrittlement of weld metal, HAZ and base metal obtained by 2 mm V notched Charpy test was quite proportional to prestrain, and significant difference among them could not be found. The equations for estimation of the brittle fracture initiation temperature were checked. The rise in the temperature caused by the pre-loading was less than that due to the weld residual stress. It was concluded that the effective pre-loading method recommended in the present paper was sufficiently safe.
著者
大橋 修 菅 誠一郎
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.10, no.1, pp.53-58, 1992-02-05
被引用文献数
8

The purpose of this study is to investigate the effect of twist angle on tensile strength of diffusion-welded joints by using molybdenum single crystals with (121) and (025) surfaces. Relation between the twist angle and strength is tried to explain with the coincidence site lattice model and a theoretical model calculation. The results are as follows : Single crystals could be welded without recrystallization. Tensile strength of the joints depended on the twist angles. The joints with twist angles up to 10 degree were as strong as the base metal. In case of the twist angles above 10 degree, there were peaks in tensile strength of the joints around the certain twist angles where a number of common lattice points were formed at welding interface. From the calculation, it was shown that the binding energy between the crystals decreased with decreasing the number of common lattice points. Twist angle widths of peaks in tensile strength were estimated with the Brandon's equation.