Phase quantification in nanobainite via magnetic measurments and X-ray diffraction

W. Solano-Alvarez, H. F. G. Abreu, M. R. da Silva and M. J. Peet

Journal of Magnetism and Magnetic Materials, Vol 378, (March 2015), 200-205.

DOI: 10.1016/j.jmmm.2014.11.037

Abstract

Accurate phase quantification of nanostructured bainitic steel is of importance because of the nature of its percolating structure that controls many of its mechanical properties. X-ray diffraction is the technique of choice for such analysis, but magnetic methods can be more rapid and less sensitive to defect structures. In this study, the phase volume fractions measured using both of these techniques for the specific mixtures associated with nanostructured bainite have been compared and contrasted. An expression which relates the volume fraction and the saturation magnetisation is obtained and its form is found to be consistent with previous work done on duplex stainless steels and TRIP steels. The fitting constants used in many of such analyses vary significantly so an attempt is made to rationalise the differences by considering the factors that determine the intrinsic saturation magnetisation of ferrite.

Keywords

nanostructured bainite, phase quantification, saturation magnetisation, X-ray diffraction