|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Ultrafine Grained Materials IX
||Nitriding of Nanocrystalline Metals Generated by Ultrasonic Nanocrystal Surface Modification
||Jingyi Zhao, Zhencheng Ren, Guoxiang Wang, Yalin Dong, Chang Ye
|On-Site Speaker (Planned)
Ultrasonic nanocrystal surface modification (UNSM) is an innovative surface processing technique that takes advantage of low amplitude ultrasonic vibrations superimposed on static load to induce severe plastic deformation (SPD) that leads to surface nanocrystallization in metallic materials. In this study, surface nanocrystallization has been achieved in pure iron and 4140 steel through UNSM. It has been reported that nitrogen diffusion rate in grain boundaries is much higher than that in grain interior. Due to the high fraction of grain boundaries in the nanocrystalline metal, the nitriding efficiency is significantly higher in the UNSM-processed metals than that in the non-processed metals. Through the combination of UNSM processing and nitriding, a super-hard surface with strong corrosion resistance can be created, making it a promising process for industrial applications.