A Study on Improving the Cooling Performance of EV Motors Using Non-Magnetic SUS Material

Hunyoung Park･Jongcheon Kim･SungHwan Park (Hyundai Motor)

Research on the magnetization properties of SUS for electric vehicles according to the molding amount of SUS material is lacking. This study quantitatively analyzed the critical magnetization level of SUS according to material and molding amount using a reliability method, and discusses solutions and results.

A Study on Reducing Eddy Current Loss by Designing of Nd Sintered Magnet

SeokJin Ha･Jae Ryung Lee (Hyundai Motor)･Sang Hyub Lee (STAR GROUP IND.CO.,LTD.)

We present manufacturing method of the segmented NdFeB magnet for reducing eddy current loss. The key idea is that the manufacturing process of segmented magnet can be simplified by changing the direction of GBDP of HRE from parallel to magnetization easy axis(C-axis) to perpendicular to magnetization easy axis(A-axis). By reducing the number of cutting and bonding process, the manufacturing cost of segmented magnet can be reduced. Also the application effects of the segmented magnet in the unit of the traction motor are evaluated as well.

Wear Charactaristics Evaluation of Engine Valve-Valve Seat Material Combinations

GAYEON KIM (Hyundai Motor)

This study investigated wear characteristics of engine valve-valve seat material combinations using three valve steels and four valve seat materials (12 combinations total). A specialized wear testing apparatus simulated actual engine conditions, achieving significant cost and time savings compared to full-engine testing. Results showed minimal wear differences among valves across combinations, while valve seats exhibited substantial variation. The optimal combination was successfully identified. Wear characteristics could not be predicted from individual material properties alone, emphasizing the importance of material interaction analysis. This data provides valuable reference for engine component material selection and design optimization.

A Study on Friction Stir Butt Welding of Ti alloy for Aerospace

JAEYOON HWANG (Hyundai Motor)

Titanium has been commonly used for aircraft among metal materials, and Ti-6Al-4V alloy has been mainly used because of its excellent specific strength, corrosion resistance. However, a joining method that can omit fastening components in structural parts is being studied for the purpose of further weight reduction of parts using titanium. Ffriction stir welding, a solid-state welding method, is performed at a lower temperature than fusion welding and has less deterioration in mechanical properties. In this study, I've analyzed the microstructural changes and mechanical properties of FSW for Ti-6Al-4V, and also examine the effects of structural factors such as hook formation, effective sheet thickness and effective lap width on mechanical performance in overlap-type joints for aircraft structures.