Abstract
The purpose of this work is to present experimental results of impurity elimination during electron-beam melting (EBM) of SUS 304 and NCF-1 alloys. A continuous drip-type EBM furnace of 30kW max. Power and water cooled copper mold of 55mm in inner diameter were used. SUS 304 alloy was twice melted at a given melting rate, while NCF-1 alloy was melted for once. Concentration changes of elements in the alloys were summarized as follows:
Remarkably decreased: Sb, O, Mn for SUS 304, and Pb. Bi, O, Mn for NCF-1.
Decreased: Cu, Zn, N, Cr, for SUS 304, and Cu, Sb, N, Cr for NCF-1.
Slightly decreased: As, Pb, (Sn, S) for SUS 304, and Sn, S for NCF-1.
Unchanged or increased: Si, P, Al, Ni, C.B, for SUS 304 and As, C, Si, P, Ni, Fe for NCF-1.
NCF-1 alloy was also melted by VAR, ESR, MSR, and PAM by using laboratory-scale furnaces. Removal degree of impurities during these melting processes were compared with that of EBM as to certify the superiority of EBM for the impurity removal.
