Gas-Carburizing Kinetics of a Low-Alloy Steel

作者：Nobili Luca^*; Cavallotti Pietro; Pesetti Mariella

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2010, 41A(2): 460-469.

DOI：10.1007/s11661-009-0102-0

Gas-carburizing kinetics of a low-alloy steel (Pyrowear 53) was investigated by thermogravimetric experiments. Kinetic curves were modeled by adapting the approximate integral method, and the diffusion coefficient of carbon as well as the rate constant of the surface reaction were estimated. These parameters were evaluated after several carburizing procedures, which differ from each other in the surface treatments performed before the carburizing step. It is known that the carbon enrichment is low when this steel is carburized without any pretreatment, and this behavior was found to be related to a low value of carbon diffusivity. The interaction between the selective oxidation of alloying elements by the carburizing atmosphere and carbon diffusion is discussed. The pretreatment procedures investigated in this work consist of different combinations of oxidation, reduction, and grit-blasting processes. The most effective procedures involve oxidation in dry air or oxidation in wet air followed by grit blasting.

• 出版日期2010-2