New Type Fe-Mn Based Alloys with Super Elinvar and Invar Characteristics

Abstract

In the present study, both excellent Elinvar and Invar characteristics have been found in the antiferromagnetic Fe-Mn based alloys consisting of about 25 mass%Mn and a small amount of Mo, W, Nb, Ta, Ti, Zr and Hf which are belonging to the 4～6 families in the periodic table. The best characteristics obtained in the present study were constant Young's modulus (Elinvar characteristics) of 1 × 10⁻⁶ K⁻¹ and a small thermal expansion coefficient (Invar characteristics) of 8 × 10⁻⁶ K⁻¹ in the temperature range of 293～353 K under appropriate treatment of cold working and annealing. Such alloys will be expected as applications in a wide field such as precision instruments, electromagnetic devices and controlling devices.