Elinvar Properties of Mn-Pt Alloys

Abstract

The thermal expansion, Young’s modulus, magnetic susceptibility and electrical resistivity at −150∼500°C, and the hardness and density at room temperature have been measured with annealed Mn-Pt alloys. It has been found that Mn-10.05∼40.21%Pt alloys slow cooled after heating at 1100°C for 4 hr have distinct anomalies near the antiferromagnetic Néel point in the Young’s modulus vs temperature curves. The temperature coefficient of Young’s modulus at room temperature vs composition curve exhibits a large positive maximum at a concentration of 30.10%Pt, thus revealing the Elinvar property in this alloy system.