高压液氨装置用大型锻件的焊接修复

介绍了大型锻件的焊接修复工艺的制订以及焊后热处理,通过两年的运行表明,该焊接工艺可靠安全。     

Numerical analysis of welding residual stress using heat source models for the multi-pass weldment

Numerical prediction of welding-induced residual stresses using the finite element method has been a common practice in the development or refinement of welded product designs. Various researchers have studied several thermal models associated with the welding process. Among these thermal models, ramp heat input and double-ellipsoid moving source have been investigated. These heat-source models predict the temperature fields and history with or without accuracy. However, these models can predict the thermal characteristics of the welding process that influence the formation of the inherent plastic strains, which ultimately determines the final state of residual stresses in the weldment. The magnitude and distribution of residual stresses are compared. Although the two models predict similar magnitude of the longitudinal stress, the double-ellipsoid moving source model predicts wider tensile stress zones than the other one. And, both the ramp heating and moving source models predict the stress results in reasonable agreement with the experimental data.     

高耐磨合金柱及专用焊接设备

高耐磨合金柱及专用焊接设备是一种新型的磨损防护系统,它是在易磨损工作面上采用特殊焊接方式（无需任何焊条）焊接高耐磨合金柱。该设备的研制成功可使易磨损工作部件的使用寿命提高３～４倍,可从人力、物力、电力等方面大大降低工业成本及辅助作业成本,降低劳动强度,提高生产效率。试验证明,高耐磨合金柱及专用焊接设备是一种高效、实用、低成本的提高设备耐磨性能的方法和设备。     

螺旋埋弧焊管焊缝形状参数分析

螺旋焊管焊缝形状的好坏,直接影响焊缝接头服役时的力学性能、焊缝的内部质量以及防腐涂层的成本,并反映焊接工艺参数选择的合理性。分类描述了焊缝形状的几何参数（选择性参数和操作性参数）,重点论述了焊缝的余高、熔宽、熔深、熔合比、重合度、过渡角、错边量、焊偏量等参数及其对焊接质量的影响。     

X60钢级管线钢焊接热影响区的热模拟研究

采用焊接热模拟技术对X60钢级管线钢进行了热影响区模拟试验。研究了该钢在不同的峰值温度和冷却时间下的韧性和组织,测定了其热影响区的硬度。结果表明,峰值温度越高X60钢级管线钢的组织越粗大、韧性越低;在不同的峰值温度下,冷却时间对该钢焊接热影响区组织及韧性的影响是不同的。     

铝及铝合金用钎剂的发展现状和趋势

综述了铝及铝合金用钎剂的发展概况.根据其组织结构和表面特性分析了钎剂在焊接时必须具备的独特性能,依此详细介绍了铝用钎剂的种类和优缺点.同时也对钎剂焊接时的作用机理作了深入探讨,最后阐述了铝及铝合金钎剂的未来研究方向.     

药芯焊丝混合气体保护焊在压路机转向机构焊接中的应用

从压路机焊接式转向机构的材质、结构和焊缝布置入手,对焊接工艺性进行详细分析,从而得出尽管转向机构材质的可焊性较好,但由于构件的板厚较大且构件间板厚不均匀而导致转向机构焊接工艺性较差的结论.结合压路机转向机构工作环境恶劣、转向转矩大和焊接质量要求高的工作特点,以及药芯焊丝混合气体保护焊生产率高、焊接质量好和综合成本低等优点,从焊接方法、焊接参数选择、焊接环境及焊接工装选用等方面对压路机转向机构的焊接工艺进行深入探讨.在应用药芯焊丝混合气体保护焊焊接转向机构时,综合考虑焊接参数、焊接环境和焊接工装等因素,制定合理的焊接工艺并在生产中严格执行,能有效保证转向机构的焊缝质量.经检验证明,选用的焊接方法和制定的焊接工艺是合理有效的.     

Friction Stir Knead Welding of steel aluminium butt joints

To develop steel aluminium-tailored hybrids in a butt joint for sheets in a thickness of about 1 mm conventional Friction Stir Welding is not feasible due to a high distortion of the welded specimen. Contrary to Friction Stir Welding the tool used for Friction Stir Knead Welding has no pin wherefore higher welding speeds can be realised. Due to the fact that this is a newer process, applied for patent in 2005, the cut contours of the edges and their variations have to be optimised by numerical analysis to transfer a maximum of load in order to improve the formability. The examined materials in this paper are steel DC04, as well as the aluminium alloys AA5182 and AA6016 in sheet thicknesses of 1 mm. Accompanying experimental investigations, as tensile tests, will evaluate the quality of the welding mechanism. As the mechanics of the new welding technology is not fundamentally investigated until now, metallographic investigations are performed, and additionally micro hardness measurements are carried out to verify the changes in the hardness distribution in the welding zone after stirring and welding.     

焊弧的电磁辐射研究

焊弧是大功率的用电负载；手工电弧焊中焊工距焊弧较近，研究焊弧的电磁兼容问题是有实际意义的，本文分析了焊接的形成机理，论述了焊弧电磁辐射的计算方法，给出了三维图形，对焊弧的辐射进行了测量，并对各个结果作了分析比较。