Decomposition of Ni-23 at.% Si and formation of Ni3Si

Abstract

The purpose of the paper is to outline the formation of Ni3Si from Ni-23 (at. %) Si. The Ni-23Si was annealed at 1130°C for 24 h and quenched, after which it consisted of ∼10μm particles in an otherwise single phase matrix. To produce the peritectoid transformation to Ni3Si, samples were annealed at 725°C.Thin foils of Ni-23Si were prepared by electropolishing 250μm thick discs with 13% hydrochloric acid in methanol in a Struers Tenupol at -40°C, 40V (200 mA) and a medium flow rate. After perforation, the thin foils were rinsed in ethanol before washing in hydrofluoric acid for 30-40s. The foils were examined in a JEOL 2000FX TEM, furnished with a Tracer Northern TN5500 EDS system.