Applications of Auger Electron Spectroscopy in Ferrous Metallurgy

Abstract

From its introduction , Auger Electron Spectroscopy (AES) has been applied to a number of long-standing problems in the metallurgy of iron and steel. It has made enormous impact in the general areas of intergranular embrittlement and surface segregation, and it has begun to contribute to the understanding of interface-controlled phase transformations. This chapter discusses the application of Auger electron spectroscopy (AES) in the study of impurity-induced intergranular fracture, segregation of solutes to free surfaces, and effects of surface-active solutes on the kinetics of phase transformations. It discusses the problem of quantitative Auger analysis, which is the establishment of surface concentrations from measured peak heights or peak height ratios. The chapter describes a calibration method for relating experimental values of Auger peak heights dN(E)/dE to surface concentrations. The chapter discusses some recent ideas on the physical basis for reduction of intergranular cohesion by impurity segregation and reviews surface studies in Fe–Sn, Fe–C, Fe–N, Fe–S, Fe–Si alloys, and impurity-doped Ni–Cr steels. It also reviews the work done on the effects of impurity segregation to solid–liquid and solid–solid interfaces in cast irons.