A perspective of niobium in superalloys

The central objective of this paper is to characterize the metallurgical behavior of niobium as an alloying element in austenitic superalloys. To accomplish this, we will first define, then describe superalloys in some detail as background. Next, niobium itself will be reviewed with respect to its properties appropriate for superalloy constitution. Then the specific function of niobium as additive to nickel, cobalt and iron-based superalloys will be established and its broad effects summarized. (AU)