An X-Ray Study of the Iron-Nickel-Aluminium Ternary Equilibrium Diagram

Stimulated by the special interest of iron-nickel-aluminium alloys for the permanent magnet industry, we have made an X-ray investigation of this system. The information obtained has led to a new view of the nature of the permanent magnets of iron, nickel and aluminium, which has been briefly described elsewhere (Bradley and Taylor 1937 a, b, c ). In the present paper we confine ourselves to a description of the X-ray results, which have enabled us to draw a complete ternary diagram representing the phases formed by these metals. The iron-nickel-aluminium alloys are closely related to the systems FeAl, NiAl, CoAl. Every phase which occurs in the ternary system has an analogy in one or another of these binary systems. This makes it possible to interpret the present results in the light of our previous knowledge of those systems.