A study on the manufacturing characteristics of new materials for electric vehicle drive motor

Abstract

Research has been conducted on the material trends and manufacturing characteristics of the drive motor, which is one of the three core technologies of electric vehicles. To develop high-efficiency and vibration-free motors, automobile manufacturers are considering various design changes, material modifications, and alterations in manufacturing methods for the drive motor. Typically, the drive motor core is stacked using 0.25–0.3t steel plates in both emboss-type and welding-type configurations. However, there is a shift toward a bond-adhesive lamination method using self-bond material to create high-efficiency motors. The self-bond method is a layering method using bond-coated steel plates. In this study, we investigated the factors affecting the induction and convection heat fusion temperatures, temperature distribution characteristics, and stacking factor of heat-fused products using self-bond material. Additionally, experiments were conducted to analyze the heat transfer properties during the fusion process and the temperature distribution changes over time. In the heat fusion experiments, induction resulted in temperature increases of 277.1 °C (Zone ①), 161.4 °C (Zone ②), and 103.2 °C (Zone ③) after 120 s of heating. Carbonization occurred due to higher temperature rise in Zone ① compared to Zones ② and ③. On the other hand, convection required 330 min to reach a product fusion temperature of 209 °C, but the temperature deviation was more uniform compared to induction. Furthermore, we analyzed the plate thickness, glue coating thickness, and weight of self-bond material Lots A and B. The experimental results for the stacking factor before and after fusion showed that Lot B had a stacking factor of 96.98%, which was 0.48% higher than Lot A. The fusion process significantly influenced the stacking factor.”