Induction Annealing of Austenitic Spring Steels for Nuclear Reactors

Abstract

This paper describes designing and experimental trials of an induction annealing method for AISI 321H austenitic steel wires. Specifically, it explores the feasibility of incorporating an existing frequency controller into a wire drawing line to provide induction heating of the wire stock to annealing temperatures. In-process annealing is necessary to make cold wire drawing possible by restoring the ductility of the wire stock. The reason is that the wire products are required to have strengths in excess of 1600 MPa in some cases. Hence, the only way to meet this requirement is to apply severe deformation combined with sufficiently effective polygonization.