熔化极气体保护焊的仿真系统

焊接过程的仿真被认为是未来焊接技术发展的主要驱动力之一，它可对焊接过程中的物理现象、接头形态、热变形及微观组织做出预测，从而部分取代新产品和新工艺开发中耗时而昂贵的实物试验，并加快开发过程。作者提出了一个熔化极气体保护焊仿真系统的数学模型，它用系统化的、以有限差分为基础的数值算法来模拟焊接过程中的热流、电磁流和金属流，并把焊接电源、电弧特性、送丝机构等有机地结合起来，为进一步研究焊接机理、预测微观组织和力学性能、计算工件的变形等提供了一个数学平台。文中使用该数学模型对金属过渡、熔池振荡及系统动态反应等做了分析，得到一些用试验观察法或解析法难以得到的结论。

Research on simulation systems of MIG welding

Simulation of welding process is considered as a major driving force of the development of welding technology in the 21 stcentury.It makes predictions of the physical phenomena,joint geometry,welding distortion and microstructure so as to partially replace the time-consuming and costly experimentation in the development of new welding procedures and shorten the development period.In this paper,a simulation model is developed for the MIG welding process.Systematic and finite-difference-based numerical algorithms are desiged to simulate the thermal,electromagnetic and metal flows.The characteristics of welding power source,electric arc and wire feed device are also integrated into the system.It will provide a mathematical platform for the further study on welding physics,microstructure,mechanical properties and workpiece distortion.Analysis has been also conducted to study the metal transfer,weld pool oscillation and electric response.Some conclusions that are difficult to obtain by using experimental and analytical methods have been drawn.