Investigation of local properties of the Fe-Si alloy subjected to mechanical and laser cutting

Abstract

The effective design of energy-saving electric motors with efficiency class IE4 and higher requires the use of material characteristics that take into account the core shaping process. Therefore, it becomes necessary to use analytical or numerical models that take into account the change of local properties of Fe-Si material. The aim of the work is to indicate a useful analytical model for estimating the local magnetic permeability of the material, as well as to understand the reasons for these changes. For this purpose, low-loss ferromagnetic materials cut with a guillotine and a laser were tested. Rectangular samples, cut at an angle of 0 degrees in relation to the rolling direction, were subjected to macroscopic and microscopic examinations. Finally, the main reasons for changes in material characteristics for both cutting technologies were indicated. Therefore, the proposed model takes into account not only the cutting technology used, but also the current width of the tested strip, for which the material characteristics are to be determined. The parameters of the analytical model are determined on the basis of a limited number of measurements carried out on samples of a simple geometric shape.

Mechanical and Magnetic Properties Variation in Non-Oriented Electrical Steels with Different Cutting Technology: A Review

“…As previously mentioned, plastic and elastic deformations and residual stresses due to the cutting procedure have an important influence on the degradation of the material’s macroscopic properties. This phenomenon is emphasized at low strains below 5% and in the low and medium magnetic field strength domain of kA/m order [ 55 , 56 , 57 ] ( Figure 3 ). In Table 3 are summarized some studies, which analyze the residual stress distribution and hardness values near the cut edge.…”

“…In the case of laser cut samples, the maximum values reached were 270 HV 0.1 -M300-35, and 160 HV 0.1 -M470-50. The damaged zone width was estimated at 70-80 µm[57] NO FeSi with 2.4 wt.% Si, thickness of 0.35 mm and 0.5 mm PunchingIn the area placed near the cut edge were numerically identified compression and tension stresses of about 250 MPa. Compression stresses in the cross-sectional area were determined in the middle of the blank.…”