Modeling of Spray Cooling during Induction Hardening of Spur Gearwheels Made from 42CrMo4 Hardening and Tempering Steel

Abstract

The application of water-air spray cooling in the process of induction surface hardening according to the simultaneous dual-frequency technology represents a hitherto unexploited and equivalent alternative to conventionally employed polymer solutions. The reason for this is that the selection of the optimum parameters is associated with a high experimental outlay and analytical effort for performing the tests and evaluating the results, respectively, and the parameters must be selected for a specific application. In order to reduce this effort, a numerical model was developed to formulate the coupled thermal, microstructural, and mechanical processes during quenching by means of water-air spray cooling of induction heated spur gearwheels made from 42CrMo4 hardening and tempering steel. The model was implemented in the commercial simulation software ANSYS Workbench 13.0 and verified using simulation results for temperature development, hardness distribution, residual stresses, and distortion. A comparison of the simulated and experimental results show that the model introduced here is suitable for predicting the hardening results during quenching using spray cooling subsequent to induction heating.

Analysis of Continuous Induction Hardening of Steel Cylinder Element Made of Steel 38Mn6 / Analiza Przelotowego Hartowania Indukcyjnego Walca Ze Stali 38Mn6

“…As a result a thin surface layer with required values of hardness and microstructure is obtained [1][2][3][4][5]. The internal part of the treated element remains soft with not changed values of hardness and with the practically the same microstructure as before starting the process.…”

Transient contact behavior of aqueous polymer solution droplets with transparent hot solid

“…Aqueous polymer solutions are widely utilized as a cooling medium in quench hardening processes to strengthen hot carbon steels [1][2][3][4][5][6]. Hot materials are rapidly cooled from approximately 750-900 °C to a certain specific temperature to induce martensitic transformation, and then, a moderate cooling rate is imposed on the materials to prevent unwanted quench-crack initiations or distortion of products.…”

“…Several previous works [2][3][4][5][6] have focused on the cooling process in industrial heat-treatment applications using aqueous polymer solutions. The main interests of these studies were the measurement of the temperature histories of materials and the determination of the heat transfer coefficient.…”

Technological possibilities of plasma hardening

“…Various methods for rapid intense heating of surface layers of metal are applied for that purpose. The most widely used methods are: a heating by high-frequency currents [5][6][7][8][9][10][11][12][13][14], a laser heating [15][16][17][18][19] and a gas-flame heating [20][21], a plasma heating [22][23] is used for very limited applications.…”

“…Heating by high-frequency currents has become widespread [5][6][7][8][9][10][11][12][13][14] but its application is limited by the inability to localize the heat source in confined areas and by the low efficiency of converting of electrical energy into thermal one in the heating zone.…”