1061. ---------------. [FORESTIER, H., AND NURY, G.] [Speeds of Reaction in the Vicinity of Magnetic Transformation Points. Application to the Cementation of Iron.] Bull. soc. chim. France, 1949, D, pp. 193-196; Chem. Abs., vol. 43, 1949, p. 6018.

1061. -------------. [FORESTIER, H., AND NURY, G.] [Speeds of Reaction in the Vicinity of Magnetic Transformation Points. Application to the Cementation of Iron.] Bull. Soc. Chim. France, 1949, D, pp. 193-196; Chem. Abs., vol. 43, 1949, p. 6018.

Rate of formation of ferrite from NiO and Fe₂O₃ is studied near the Curie point. Maxima in the % product are observed at 590° and 675°, the Curie points of ferrite and Fe₂O₃, respectively. These maxima are attenuated as the time of heating at 450°-800° is extended from 2 min. to 24 hr. The conclusion is that the magnetic transformation acts essentially on the chemical reaction and not on the speed of diffusion. The cementation of Fe in illuminating gas and in CO is also studied by measuring the variation of electric resistance of an Fe wire and the variation of electric hardness of an Fe cube. Pronounced maxima are observed at the Curie temperature of Fe. Similar results are indicated for the nitridization of Fe.