Al-Cr-Cu三元合金系相图的室温截面

本文用X射线粉末衍射法研究了Al-Cr-Cu三元合金系相图的室温截面。截面中出现了五个新相,称为ω₁,ω₂,ε_f,ε_x和γ_x,即共有19个单相区,41个双相区以及22个三相区。γ_x相属正交晶系,它可能是一个固定成分的化合物。 关键词：

THE ROOM TEMPERATURE SECTION OF THE PHASE EQUI-LIBRIUM DIAGRAM OF THE Al-Cr-Cu TERNARY SYSTEM

The room temperature section of the phase equilibrium diagram of the Al-Cr-Cu ternary system has been investigated by means of X-ray powder diffraction method. Beside the single phases of the three binary systems, there exist five new phases in the diagram, which we call ω₁, ω₂,ε_f, ε_x, and γ_x phase, so that the diagram of the system is divided into 19 single-phase regions, 41 two-phase regions, and 22 three-phase regions.The new phase γ_x has an orthorhombic cell, its diffraction pattern is similar to that of γ₂. By comparing with that of γ₂, we find that some strong diffraction lines are absent in γ_x, and some other strong diffraction lines exist, therefore the crystal structure of γ_x differs from cubic, and has an orthorhombic cell. It exists in such a narrow region, that it may probably be a compound.The other new phases ω₁ and ω₂ are very similar to each other in their feature. The new phase ε_f has a comparatively wide range in composition, and it seems to change rather continuously in its diffraction pattern as the composition is changed. On the other hand, the new phase ε_x has only a small region, and the diffraction pattern is completely diffrent from that of the other new phases.