Interfacial energy and match of cold pressure welded Ag/Ni and Al/Cu

The technology of cold pressure welding was adopted to achieve the bonding of Al/Cu(limited soluble and forming compounds),Ag/Ni(hardly mutual soluble),and the relative state of interface was tested by HREM.The results indicate that stable interface is always corresponding to the low interfacial energy value;the stable interface is not coherent but partly-coherent because of the twisting of grain boundary caused by pressure,meanwhile existing dislocation.Namely,the interfacial match and other states under the condition of cold pressure welding are different from the situation that under the condition of thermal action.Moreover,theoretical analyses and calculation on the base of thermodynamics,crystallogeny ,solid physics etc,were discussed.     

压力容器环缝焊接自动跟踪系统的研究

作者研制了一种新型摆动式电弧传感器及其焊缝自动跟踪系统。采用计算机控制，成功地应用于压力容器的环缝脉冲ＭＡＧ焊工艺。实践证明采用这种系统跟踪精度高并获得了优质焊缝。     

微机控制热丝GTA全位置焊管系统

本文介绍了新开发的微机控制热丝钨极氢弧焊焊管系统，旨在提高焊接速度及质量以适应生产发展的需要，控制系统利用焊接电板为传感器，通过软件来实现焊接程序、焊接规范的自动变换，焊接参数的自动控制及以焊缝的自动跟踪和示教跟踪，具有抗干扰性强，精度高，反应快、柔性强及体积小等优点，特别适合于野外现场施工。     

埋弧自动焊在大口径钢卷管焊接上的应用

为把埋弧焊应用在大口径钢卷管焊接上,分析了焊接工艺设计、焊接工装设计和纵缝、环缝焊接的施工要点,经过实际施工验证了这种方法是成功的,效益是高的。     

A novel arc welding inverter with unit power factor based on DSP control

A novel inverter power source is developed characterized with constant output current and unit power factor input. Digital signal processor （ DSP ） is used to realize power factor correction and control of back-stage inverter bridge of the arc welding inverter. The fore-stage adopts double closed loop proportion and integration （PI） rectifier technique and the back- stage adopts digital pulse width modulation （ PWM） technique. Simulated waves can be obtained in Matlab/Simulink and validated by experiments. Experiments of the prototype showed that the total harmonic distortion （THD） can be controlled within 10% and the power factor is approximate to 1.     

磁粉探伤焊缝区反常显示成因分析

研究了中碳钢焊缝区磁粉探伤出现的假磁痕,对焊接过程和焊缝组织进行分析,制订出合理的焊接工艺,避免表面缺陷检测的误判。     

药芯焊丝气体保护焊在高压Cr-Mo钢管上的应用

采用钨极惰性气体保护焊(GTAW)打底与药芯焊丝气体保护焊(FCAW)填充、盖面的焊接方法对ASME SA-335 P22和ASME SA-335 P11钢管做了焊接工艺评定。分别对其焊缝进行了拉伸、弯曲、冲击和硬度检测等力学性能试验，并通过金相照片对焊缝的微观组织进行了分析，结果证明工艺评定焊缝的各项力学性能指标都达到了ASME Ⅸ的要求，该焊接方法在实际生产中是可行的。     

Microstructures and mechanical properties of welded Fe-12Cr-20Mn austenitic stainless steel

The effects of welding on the tensile and fatigue properties of fully annealed and cold-worked Fe-12Cr-20Mn austenitic stainless steel were evaluated. Room temperature and 500 °C tensile tests and room temperature cantilever beam fatigue tests were accomplished on specimens that contained autogenous bead-on-plate welds. The tensile and fatigue properties of the fully annealed material were not significantly influenced by welding. The tensile properties of the welded cold-worked material were also not significantly affected by the presence of a weldment. However, welding caused a large reduction of the fatigue life of the cold-worked material. Fatigue cracks preferentially initiated at large Mn-Si inclusions that formed in the fusion zones of the weldments.     

镁合金激光焊接技术的研究现状与应用

镁在自然界中是大量存在的,我国的镁资源非常丰富,镁及其合金均具有许多优点,如重量轻、比强度和比刚度高、消震性能好、优良的机械加工性能和抛光性能、无毒性、无磁性、高热导率以及可回收利用等,已在汽车、精密仪器、电子、体育器械、核电、国防以及航空航天等许多领域得到了广泛的应用,具有广阔的应用前景.主要论述了镁合金激光焊接技术的现有水平与发展趋势以及镁合金激光焊接技术的应用领域及应用前景.