高速GMAW熔池流态调控与驼峰焊道抑制机理的研究

项目名称： 高速GMAW熔池流态调控与驼峰焊道抑制机理的研究

项目编号： No.51275276

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 机械、仪表工业

项目作者： 高进强

作者单位： 山东大学

项目金额： 80万元

中文摘要： 高速GMAW焊接时，熔池内动量较大的后向液体流是导致驼峰焊道缺陷的主要因素。通过向熔池施加电磁作用力，对高速GMAW熔池内流场流态进行主动干预，改变和调控熔池中的后向液体流的速度、动量及其分布，进而抑制驼峰焊道的形成。研究外加磁场对熔池后向液体流速度和动量的影响机制与作用规律。实时采集熔池后向液体流和尾部液态金属隆起区的图像，提取其形状与尺寸的变化情况，研究熔池后向液体流速度与动量的表征方法。通过实验获得不同条件下（改变外加磁场的强度、作用方向和施加位置）熔池后向液体流表征参量的测试数据。对熔池后向液体流在外加磁场作用下产生的附加电磁力进行数值计算，分析高速GMAW焊接熔池流体的受力机制及其影响因素。提出高速GMAW焊接熔池后向液体流速度、动量及其分布的调控方案与实现方式，抑制驼峰焊道的形成。为大幅度提高临界焊接速度、实现低成本与高适应性的高速GMAW焊接成形制造奠定坚实基础。

中文关键词： 高速焊接；熔池；流态调控；驼峰焊道；抑制机理

英文摘要： During high speed GMAW process, the backward flowing molten jet with higher momentum in weld pool is the main factor to cause occurrence of humping bead. Through exerting electromagnetic force on the weld pool, the weld pool fluid field is actively manipulated, and the flowing velocity, momentum and its distribution of backward molten jet are changed and adjusted, in order to suppress the occurrence of humping bead. The influencing mechanism of external magnetic field on the velocity and momentum of backward molten jet is investigated. The images of both backward molten jet and liquid metal accumulation zone at the pool tail are observed in real time, the variations of their geometry and dimension are extracted, and the method to characterize the velocity and momentum of backward molten jet is put forward. The welding experiments are conducted to measure the feature parameters of backward molten jet at the pool tail under different conditions (magnetic field strength, exerting direction and position). The added electromagnetic force acting on the backward molten jet in weld pool is numerically simulated, and the force-exertion mechanism and influencing factors are analyzed. The adjusting scheme and realizing means are proposed for controlling the velocity, momentum and distribution of backward molten jet in weld

英文关键词： High speed welding；Weld pool；Fluid flow control；Humpign bead；Suppressing mechanism