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101.
为了深入研究合金元素对铝/钢异种金属焊接接头的作用机理,以便为实际生产中焊接工艺的优化提供参考,综述了铝/钢异种金属电弧熔钎焊焊接方法及焊接接头的界面结构研究现状,并重点概述了合金元素对铝/钢异种金属电弧熔钎焊界面结构的影响。研究结果表明,在铝/钢异种金属电弧熔钎焊过程中,界面反应层的金属间化合物对焊接接头的力学性能有很大的影响。 相似文献
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Sajad Shakerin Vahid Maleki Seyyed Alireza Ziaei Mohammad Reza Rahimipour Seyyed Ehsan Mirsalehi 《Canadian Metallurgical Quarterly》2017,56(3):360-367
Diffusion joining of commercially pure titanium was successfully prepared via transient liquid phase bonding in vacuum environment. The process was carried out using AMS 4772 silver-based filler alloy at 900–1000°C for various holding time under the vacuum of 6?×?10?7?Torr. Optical and scanning electron microscopy equipped with an EDS analyzer was conducted for microstructural evaluations. Mechanical properties were also investigated by shear test, fractographic assessment and X-ray diffraction analyses. The tendency to achieve isothermally solidified joint increased by increasing bonding time. No sign of athermal solidification was detected of sample bonded at 1000°C for 90?min. Consequently, the bonding condition of a high quality joint was obtained. Elemental analyses revealed that filler alloy’s elements (Ag, Cu) distributed more uniformly in fully isothermal solidified bond, whereas the aggregation of these elements is considerable in athermally solidified bond. Shear test results represented that the highest shear strength attributed to the sample bonded in isothermal solidified condition (bonded at 1000°C for 90?min). 相似文献
104.
Amorphous metallic brazing alloys are used widely for brazing dissimilar materials, including corrosion-resisting steels. The results of detailed tests carried out in accordance with the GOST standard in tensile, impact, and bend loading are presented, and the results of non-standard torsion tests of brazed joints are also outlined. 相似文献
105.
V. I. Lukin V. S. Rylnikov N. G. Orekhov A. N. Afanasev-Khodykin V. G. Kolodochkina I. A. Galushka 《Welding International》2017,31(7):548-553
The processes of recrystallization of single crystal nickel creep-resisting alloys in brazing were investigated. The methods of preventing recrystallization of the single crystal alloys are described. The microstructure of the brazed joints in the VZhM4 and VZhM5 alloys is investigated. The effect of heat treatment on the microstructure of the brazed joints in the VZhM4 and VZhM5 alloys is described and the strength of the brazed joints determined. 相似文献
106.
通过试验研究发现,晕环是由于Cu,Ag,Sn,Mn和Au等几种元素导先钎料整体沿晶界或毛细磨痕润湿母材的结果,从而提高钎料的润湿性。液态钎料与母材的性能以及在钎焊温度下相互作用情况是影响晕环形成的主要因素。 相似文献
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108.
文章介绍了山东铝业公司电解铝厂“九五”期间一方面通过开展技术创新活动,引进,开发和推广节能“四新”技术,一方面走技术改造之路,节能降耗取得了显著成效。 相似文献
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K. Bobzin F. Ernst R. Nickel J. Rösing Dipl.‐Ing. Y. Rojas 《Materialwissenschaft und Werkstofftechnik》2007,38(7):533-537
Wear Protection of Titanium using Surface Brazing Titanium and titanium alloys possess high specific strengths up to a temperature of about 600 °C in addition to an extraordinary corrosion resistance [1]. The low wear resistance constitutes a crucial impediment for a much broader use. Titanium materials are especially susceptible to friction fatigue and erosion. Coating techniques have to be developed in order to counteract this technical constraint. Surface brazing presents a promising approach. Hard metals mixed with brazing filler metals on a silver and titanium basis were brazed in a vacuum furnace and subsequently characterized. Wear resistance was quantified and optimized using ball on disc measurements. 相似文献