STRUCTURE AND PROPERTIES OF AFA STEEL FE-NI-CR-AL WITH VARIABLE ALUMINUM CONTENT

Abstract

Aluminum-containing austenitic steels (AFA steels), which may be promising for use as structural materials in nuclear reactors with liquid metal coolant, are investigated. Six ingots of alloys with variable aluminum content were obtained by the method of arc melting in an inert environment. After homogenizing annealing and cold deformation by rolling, samples for mechanical tests and structural investigaion were made from the obtained strips, which were subjected to final annealing at the temperature standard for austenitic steels of 1050 °С. It was found that the maximum values of the yield strength and the ultimate tensile strength are observed at the aluminum content of 3.5 wt.%. It is significant that when the aluminum content is increased to 4 wt.%, the strengths and plasticity decrease. This behavior is associated with structural changes in steel.