Fine Structure of Interphase Boundaries in Hard Alloys of the Chromium Carbide–Titanium System

Abstract

The structure of interphase boundaries in hard alloys fabricated by explosive compacting of the powder mixture of chromium carbide (Cr 3 C 2 ) and titanium is investigated. It is established by electron microscopy that these boundaries have a thickness of the order of 100 nm, along which, a smooth variation in the chromium and titanium content with the almost constant carbon content is observed. The structure of boundaries is nonuniform over the thickness: a layer 5–7 nm thick with an amorphous structure is detected between two crystalline interlayers. It is shown that these layers are the layers of specific «boundary phases» matching none phases of the equilibrium phase diagram of the Cr–C–Ti system.