The magnetic testing of the ferrite content of austenitic stainless steel weld metal

Abstract

The need for a well-founded and fundamental method of determining the δ-ferrite content in austenitic stainless steel weld metal is discussed in the context of solving the problem of determining an internationally agreed procedure for non-destructive ferritometers; the work of the International Institute of Welding on this topic is discussed. The results of work carried out in the USSR on the chemical composition and saturation magnetization of δ-ferrite, on the FC-2 ferrite content measuring device, and on the correlation of the USSR δ-ferrite percent and the USA ferrite number are reported. The magnetic saturation method is proposed as the arbitrary, standard method of calibrating non-destructive ferrite content measuring devices.