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.

The Effect of Surface Hardening on The HQ 705 Steel Camshaft Using Static Induction Hardening and Tempering Method

“…In this study, the induction machine singlephase 220V (50/60Hz) is used for induction hardening, where oil was used as a cooling fluid in the quenching process [14]. A handmade coil with 2 turns of wire was prepared to harden the specimen with a 4 mm gap to the outer diameter of the specimen [15]. First, the induction hardening process in specimens 1 and 2 was carried out with an output current of 747 A for 15 and 20 seconds.…”

Comparison of Industrial Quenching Oils

“…For this reason, it is useful to model the heat transfer process for the entire quenching period. Božidar Liščić has shown that one way to obtain a correlation between the quenching rate and hardness is to integrate the cooling curve [3,13]. A similar method was proposed by K. E. Thelning, who showed that integration yields the area under the cooling curve between two critical temperatures T 1 and T 2 .…”