Development of a Kinetic Model of the Growth of Boroaluminized Diffusion Layers by Finding the Activation Energy from a Given Experimental Dependence

Abstract

The thermal-chemical treatment of metals, such as boriding and boroaluminizing, significantly improve the performance properties of machine parts and tools by forming protective diffusion layers on the surface of products. The thickness of the resulting layers is one of the determining factors affecting the properties. To control layer growth, it is important to know the kinetic parameters that govern it during high-temperature holding. The problem of determining the activation energy of boron is considered in order to identify the growth kinetics and predict the thickness of the boroaluminized layer on steel 45. On the basis of experimental data, a model for calculating the activation energy and thickness of a diffusion layer, which characterize the kinetics of the boroaluminizing of the diffusion layer, is proposed. The activation energy of the formation of a boroaluminized layer in pastes on the surface of steel 45 is calculated according to the parabolic dependence of layer growth as a function of temperature and time.