Distortion in Induction-Hardened Cylindrical Part

Abstract

This article concerns distortion of a workpiece after induction-hardening under various conditions. It focuses particularly on the effects of quenching water temperature, PAG polymer concentration and the rotation speed of the workpiece during induction hardening. Electrical as well as non-electrical quantities which affect the process were monitored. They included the current passing through the inductor, the power frequency, quenching water temperature, the flow rate of the quenchant through the spray-quench device, the speed of rotation of the workpiece and some others. The workpiece was a cylinder 70 mm in length which contained a drilled off-axis through hole. Prior to hardening, dimensions of the workpiece and the hole were measured on three planes set in different distances from the bottom face. The measurement was repeated after induction hardening and the findings are reported in this article. Post-process hardness was measured on the cylindrical surface of the workpiece. Hardening depths obtained with different quenchants were measured.