Ti40Zr25Ni15Cu20非晶钎料钎焊Si3N4陶瓷的界面结构及强度

采用Ti40Zr25Ni15Cu20非晶钎料进行了Si3N4陶瓷真空钎焊连接,利用SEM、EDX等微观分析手段,研究了钎焊界面的微观结构,得出界面反应层有两部分组成,接头界面微观结构为Si3N4/TiN/Ti-Si,Zr-Si化合物/钎缝中心;在相同钎焊工艺条件下,研究对比了晶态和非晶态钎料钎焊接头的强度,发现非晶态钎料钎焊的接头强度大大超过用晶态钎料钎焊的接头.     

铝/钢异种金属电弧熔钎焊界面结构的研究现状

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。     

镀锌板激光钎焊接头拉伸性能研究

文中使用2kW Nd:YAG激光,对0.88mm厚的镀锌板进行了激光钎焊实验,采用T形接头形式,焊丝为0.8mm CuSi3,通过优化选择工艺参数,获得了成型良好的钎焊接头,通过钎焊接头厚度的加强,在拉伸实验中,钎焊接头的强度超过了母材.     

火焰筒后段通道组件真空钎焊

对钣金涨型结构件--XX火焰筒后段通道组件的真空钎焊进行了研究,详细介绍了钎料预置和规范参数选择,其钎料预置采用粘带、粉、膏状镍基钎料Amdry915联合运用.实验结果表明,采用所制定的钎焊规范,钎焊出了满足要求的火焰筒,并已用于批生产.     

基于PLC和触摸屏技术的自动电弧钎焊装置控制系统研究

针对企业对钢件产品需堆焊一定厚度的低熔点合金的要求,提出了电弧钎焊的焊接工艺,开发了自动钎焊装置.主要介绍了由PLC与触模屏组成的控制系统构成、工作原理及软硬件设计.该装置具备平面内直线、圆弧线焊缝焊接、立体环面焊缝的焊接功能.实践表明,该装置的控制系统具有人机界面友好,控制方便,焊接过程指示直观、全面,焊接效率高、质量高且稳定性好等优点.该新技术在航空航天、船舶、化工、矿山机械等行业具有很好的应用前景.     

离子注入改进陶瓷表面可焊性机理分析

进行了Ni+( 1 3 0keV)、Ti( 1 50keV)离子注入Al2 O3(质量分数为 85% ) -ZrO2 (质量分数为 1 5% )陶瓷表面改性试验 ,对改性陶瓷材料表面进行了X -光衍射谱物相分析、表面导电性分析以及与不锈钢材料的非活性钎焊性能分析。结果表明 ,注Ni+和注Ti+陶瓷表层导电性未发现明显变化 ,而注Ti+的陶瓷表层材料在注入剂量达到3× 1 0 17ions/cm2 时其导电性有明显的提高 ,这是由于在陶瓷材料表层生成的钛氧化物的导电性较高的原故。离子注入确实可以显著提高陶瓷材料的可焊性 ,但提高陶瓷材料表面导电性并不是提高其钎焊性能的主要因素。     

Microstructural and mechanical assessment of transient liquid phase bonded commercially pure titanium

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).     

Computer methods of structural analysis

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.     

Special features of brazing VZhM4 and VZhM5 single crystal alloys

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.     

真空钎焊中晕环现象的研究

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。