电弧增材制造多层单道堆积的焊道轮廓模型函数

Study on the weld profile model function of multi-layer single-pass deposition in wire and arc additive manufacturing

焊道截面轮廓的建模和分析为电弧增材制造过程中的切片、路径规划和工艺自动化提供必要的形貌数据.采用MATLAB开发基于图像处理和曲线拟合的自适应拟合程序,可以在半椭圆函数、圆弧函数、余弦函数和抛物线函数之间自适应选择合适的拟合模型函数.基于该程序,研究分析在焊接参数可行域内单层单道焊道截面轮廓最佳数学模型函数的分布情况,以及多层单道堆积过程中不同层数上焊道轮廓的最佳模型函数.结果表明,自适应拟合程序对焊道截面的轮廓曲线拟合具有较好的精度;在堆焊焊接参数可行域中,单层单道焊道截面轮廓可以用半椭圆函数或余弦函数模型表示;而对于多层单道堆积,半椭圆函数模型对焊道最上层轮廓的拟合精度最高.

The modeling and analysis of the crosssectional profile of the weld bead provide the necessary topography data for slicing,path planning and process automation in wire and arc additive manufacturing process.MATLAB is used to develop an adaptive fitting program based on image processing and curve fitting,which can adaptively select a suitable fitting model function among the semi-elliptic function,arc function,cosine function and parabolic function.Based on this program,the distribution of the best mathematical model function of the single-layer single-pass weld bead profile in the feasible region of welding parameters,and the best model function of the weld bead profile on different layers in the multi-layer single-pass deposition are studied and analyzed.The results show that the adaptive fitting program has good accuracy in fitting the profile curve of the weld bead section;in the feasible region of deposition parameters,the profile of the single-layer single-pass weld bead can be represented by a semi-elliptic function or a cosine function model;for multi-layer single-pass stacking,the semielliptic function model has the highest fitting accuracy to the top profile of the weld bead.