2431. NEMCHINSKIĬ, A. L. AND DELLE, V. A. [Carbide Formation During Carburization.] Metallurg., vol. 13, December 1938, pp. 55-60; Met. Abs. (in Metals and Alloys), vol. 10, No. 5, 1939, p. 278; Chem. Abs., vol. 33, 1939, p. 5783. During carburizing of C steel with wood charcoal or with a mixture of wood charcoal (60%) and BaCO3 (40%), the saturation of the steel with C is not limited by the Acm line of the Fe-C diagram but continues to the formation of carbides. The limit of saturation is less with C than with a mixture of C and BaCO3. At higher temperatures of cementation the carbide formation is sometimes slower than at lower temperatures. This may be due to formation of a carbide network at high temperatures, which hinders the diffusion of the C into the austenite grains. Cr steel has a greater speed of carbide formation than plain C steel. The limit of saturation is higher for Cr-Ni than for C steel. |