The silicon-steel sheet was partially non-magnetized by directed energy deposition (DED) of NiCr powder to improve motor efficiency. Significant bending of the silicon-steel sheet was observed after the deposition, which leads to assembly problems. A finite element (FE) model was utilized to develop a new geometric design to suppress thermal bending of the silicon-steel sheet. Consequently, holes were strategically placed in the region of compressive residual stress, which led to a reduction in the bending of the sheet. In addition, preheating the silicon-steel sheet before laser deposition can control the resulting deformation. The proposed design modifications can be adopted as design guidelines to mitigate out-of-plane deformation in thin sheets subjected to thermal loading.
Palaniappan et al. (Tue,) studied this question.