Segregation of interstitial light elements at grain boundaries in molybdenum

Abstract We investigated the segregation of H, O, N and C at the grain boundaries (GBs) in molybdenum using ab initio calculations. These light elements have the short-distance interactions with GBs and show the preferential to segregate around GBs. The most energetically favorable trapping sites were found to locate right at the open space of boundaries. Such segregation is associated with the low electron density at the GBs, where the segregation energy is the lowest. Our studies would help understand the possible strengthening or weakening caused by impurities in molybdenum.