A hybrid process that combines metal additive manufacturing and milling could overcome the deficiencies of a single metal additive manufacturing process, such as poor stability, low precision, and bad surface roughness. Many researchers have performed a great deal of work related to the hybrid process. Nevertheless, few of these researchers have studied the specific switching moments between the additive and subtractive processes. To decrease the frequency of switching the parts between stations in a hybrid process, this paper presents a process planning method that is based on two types of moments for appropriate switching between welding and milling — Switching Moments to Avoid Interference (SMAI) and Switching Moments to Eliminate Cumulatinive Error (SMECE) in the vertical direction. A hybrid machining system based on arc welding and milling (HAWM) is designed. Experiments for fabricating workpieces with internal and external surfaces are performed to demonstrate the feasibility of SMAI. By performing a comparison with the existing method of milling every single layer or every few layers, we determined that the proposed method requires fewer times of switching the parts between stations and the efficiency improves in the switching process. Additionally, an experiment of a tapered-surface workpiece is carried out to indicate the efficacy of SMECE.

将金属添加剂制造和铣削相结合的混合工艺可以克服单一金属添加剂制造工艺的缺陷，例如稳定性差，精度低和表面粗糙度差。许多研究人员已经完成了与混合过程相关的大量工作。然而，这些研究人员中很少有人研究加法和减法过程之间的特定转换时刻。为了减少在混合过程中工位之间切换零件的频率，本文提出了一种基于两种力矩在焊接和铣削之间进行适当切换的过程计划方法-避免干扰的切换力矩（SMAI）和切换至切换力矩消除垂直方向的累积误差（SMECE）。设计了一种基于电弧焊和铣削的混合加工系统（HAWM）。进行了制造具有内表面和外表面的工件的实验，以证明SMAI的可行性。通过与铣削每个单层或每几个层的现有方法进行比较，我们确定了所提出的方法需要在工位之间切换零件的次数更少，并且切换过程中的效率得以提高。另外，进行了锥形表面工件的实验以表明SMECE的功效。我们确定，所提出的方法需要在站之间切换零件的次数更少，并且在切换过程中效率得到了提高。另外，进行了锥形表面工件的实验以表明SMECE的功效。我们确定，所提出的方法需要在站之间切换零件的次数更少，并且在切换过程中效率得到了提高。另外，进行了锥形表面工件的实验以表明SMECE的功效。