Effect of the composition of a titanium nickelide alloy on its structure and on the formation of the grain boundary ensemble

The structure and features of the grain boundary ensemble in titanium nickelide alloys of different composition have been investigated. Using the methods of scanning electron microscopy, x-ray structure and micro x-ray spectrum analyses, TiNi(B2), TiNi(B19′), Ti 2 Ni, Ti 4 Ni 2 O, and TiNi 3 phases have been detected in the alloys and described. The grain structures inherent in alloys of different composition have been systematized and described qualitatively and quantitatively. It has been shown that an increase in Ni concentration in the alloys decreases the grain size. The grain size distribution histograms have been constructed, the grain boundary types and morphology have been examined, and the fractions of boundaries of ordinary and special types in the grain boundary ensemble have been estimated for alloys of different composition.