2694. PICKLES, A. T., AND SUCKSMITH, W. Magnetic Study of the 2-Phase Iron-Nickel Alloys. Proc. Roy. Soc. (London), vol. 175, 1940, A, pp. 331-344; Chem. Abs., vol. 34, 1940, p. 5811. Measurements of magnetic saturation intensity of annealed Fe-Ni alloys were used to demonstrate the existence of a 2-phase field in the Fe-rich part of the system. The phase boundaries were determined at temperatures above 450°, and the relation of the equilibrium phase diagram to the thermal hysteresis observed under normal rates of temperature change was studied. At temperatures less than 850°, the diffusion processes take place very slowly in the Fe-Ni alloy, nevertheless, at 525°, annealing for even 12 hr. leads to a considerable breakdown of the single-phase alloys. |