Inductive welding systems used to make metal tubes often incorporate a ferrite impeder to limit induced electrical current on the ID of the tube under the induction coil. This paper assesses the improvement that can be achieved through the use of soft magnetic composites, instead of ferrite, and the addition of an external magnetic controller or bridge. The authors explain how they simulated the potential impact of the two design modifications and experimentally verified the results.

This paper investigates the factors that influence quenching rates and temperature distributions in steel during dilatometry testing. In a prior study, the authors assessed the performance of the cooling system in a widely used dilatometer. The goal of the current work is to develop a cooling strategy that provides more uniform and possibly faster cooling in the same system. Several alternate quench concepts are analyzed, the most promising of which uses water-cooled tubes to deliver high velocity gas through a series of jets axially aligned with the test sample. The proposed cooling apparatus and its effect on the induction heating process are assessed using CFD, electromagnetic, and thermal analyses.