UNSM Surface Technology for Manufacturing and Remanufacturing Torsion Bars for Crawler Vehicles

doi:2011.25.6.80

J. Ocean Eng. Technol. > Volume 25(6); 2011 > Article

J. Ocean Eng. Technol. 2011;25(6):80-85.
DOI: https://doi.org/10.5574/KSOE.2011.25.6.080

Suh Chang-Min,Pyoun Young-Sik,Cho In-Ho,Baek Un-Bong

School of Mechanical Engineering Kyungpook National University,School of Mechanical Engineering SunMoon University,Design Mecha Co. Ltd.,Korea Research Institute of Standards & Science

초음파 나노표면개질을 적용한 궤도차량용 토션바 제조 및 재제조용 표면 개질기술에 관한 연구

서창민,편영식,조인호,백운봉

경북대학교 기계공학부,선문대학교 기계공학부,(주)디자인메카 DM기술연구소,한국표준과학연구원 에너지인프라연구단

Keywords: Torsion bar, Remanufacturing, Ultrasonic nanocrystal surface modification UNSM, Presetting, Shot peening SP, Stress relaxation

핵심용어: 토션 바, 재제조, 프리셋팅, 쇼트피닝, 응력이완

Abstract

The Ultrasonic Nanocrystal Surface Modification (UNSM) technology improves the fatigue life of a torsion bar by inducing compressive residual stress on the surface layer. The UNSM is applied to replace the presetting method and shot peening technology. The torsion bar must be changed periodically because of a lack of durability and a phenomenon related to the stress relaxation. The torsion fatigue test specimens were made of DIN17221 material, and the results showed that the fatigue life was 5 times more than under durability test conditions. A comparison test between the commercial vehicles' presetting method and shot peened torsion bar and the UNSM torsion bar showed that the UNSM could replace the presetting method and shot peening.