EFFECT OF ADDITIVE Mg OR Zr ON INTERSTITIAL PHASES ALONG GRAIN BOUNDARY IN ALLOY NiCrMoTiNb OR NiCrWMoAlTi

A study under EM cbservation was carried out on the effect of Mg or Zr on NbC, M_(23)C_6, M_4B_3 and other interstitial phases along grain boundary in a NiCrMoTiNb alloy, as well as the effect of Mg on MC, Mv6C and /or M_(23)C_6 phases along grain boundary in a NiCrWMoAlTi alloy. Their behaviours were also discussed.