Abstract
Productive finishing of very smooth surface for dies and molds are still in huge demand in industries. The conventional method to obtain such high quality finished surface has mainly relied on the manual polishing in most cases. In some cases, concentrated energy flows such as intense pulsed laser, electron and ion beams and pulsed plasma flows have been tried or applied to treat workpiece surfaces in industries and academies. In this study, a large diameter electron beam (LDEB) with a maximum diameter of nearly 60mm was applied to treat very quickly machined surfaces of hardened alloys. The preliminary experimental studies performed on two difficult-to-machine materials, WC/Co and NAK80, have shown that surface finish could be significantly improved under optimized beam application conditions while over irradiation could worsen surface quality. The effect of EB irradiation on residual stress was explored. The defects induced by LDEB irradiation process were also observed and discussed. The mechanism of the modification mechanism, especially the interaction between the electrons and the material has also been discussed.
