<Original Papers>The Analysis of the Binary Phase Diagrams by Using the Eutectic Temperatures. (I) : On the Metallic Systems

We define φ as the difference between the melting temperatures of the two components, and σ as the difference between the melting temperature of the more fusible component and the eutectic temperature. The eutectic temperatures of the systems with compounds may be obtained by extrapolating the terminal branches of the liquidus. The φ-σ relation as the series of one component in the eutectic systems and systems with compounds shows the circular curves designated as φ-σ circles. This φ-σ relation is applicable in the systems with complete solid and liquid miscibility and the peritectic systems. The central points of φ-σ circles by their systems are arranged on the eight circles designated as centre circles, which are related to the periodic number of the periodic table and are, in turn, changing from small circle to great circle