Temperature-induced atypical oxidation in Sm2(Co, Fe, Cu, Zr)17 alloy systems: Dependency on oxygen-induced elemental migration

This paper addresses temperature and/or oxygen-induced chemical segregation of elements in the growth of oxide scale on Sm<inf>2</inf>(Co, Fe, Cu, Zr)<inf>17</inf>. Whereas, oxidation at T ≤ 573 K leads to primarily iron and cobalt segregation and subsequently their oxides, that at > 573 K, yields to largely CuO because of copper segregation. Only combination of higher sample temperature and environmental oxygen are found to have driven copper from alloy interior to its surface. Moreover, oxidation mechanism is considerably slowed down at higher temperature and is attributed to semi passivating surface copper oxide formation, impeding passage of oxygen to layers underneath to it.