“An investigation of the microstructure of the rapidly quenched powders of austenitic stainless steels”

摘要

A multi-scale study of the microstructure of the spherical and thin plate types austenitic stainless steel powders was performed. Atomizing process of obtaining the rapidly quenched powders was var-ied so were produced the powders of the different sizes and forms (spheres and plates). Methods of metallography, activation autoradiography on carbon, track autoradiography on boron, SEM, EDX, EBSD were used to study the microstructure and distribution of alloying elements with low and high magnification. The composition of austenitic matrix, segregations of the alloying elements, precipitates was determined and also was measured the lattice parameter of austenite. Effect of boron and carbon concentration on the microstructure of the spherical and also the thin plate powders was revealed. Comparison of the microstructure, composition and lattice parameter of the powders and PM HIP compacts, cladding fuel tubes products was performed for estimation of the decomposition degree of austenite and kinetics of carbo-borides precipitation.