Kinetic Study on Nickel Aluminides Formed on Monel 400 Alloy

Abstract

In this study on low temperature aluminized Monel 400 alloy, the growth kinetics of the aluminide layer are reported. Ni-based super alloy samples were aluminized for 2, 4, and 6 h at 600, 650, 700, and 750 degrees C, respectively. The morphologies and types of aluminides that developed on the Monel 400 substrate surface were examined using energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD). The thickness of the boride layer varied between 4 and 40 mu m. The temperature and duration time of treatment had an impact on the hardness of the aluminides that developed on the samples, ranging from 800 to 250 HV. By altering the treatment's temperature and duration, the reaction's kinetics were also determined. A regression model was utilized to create an equation that can estimate the thickness of the aluminized layer based on the parameters of time and temperature. The projected values of the thickness of the aluminized layers were compared to the corresponding measurements obtained through experimentation, and a satisfactory agreement was achieved. Furthermore, a contour diagram is a recommended tool for determining the appropriate thicknesses of aluminized layers based on the prospective industrial applications of Monel 400.