Case-hardening of steel components manufactured with additives

These differences will be determined in the project for two case-hardening steels, and the heat treatment required to achieve the material properties will be adapted to these particularities. First, process parameters for laser beam melting are determined for the case hardening steels 20MnCr5 and 17CrNi6-6.

At the beginning of the parameter development for the steel 20MnCr5 the formation of the melt pools was investigated in detail and a suitable parameter window was identified, which allows a sufficient welding depth. The metal powder used was examined for chemical composition and grain shape before processing. The latter is decisive in the process for the application of the powder layer and thus for a stable process. 3D samples were then produced and the density achieved was determined.

Appropriate adjustment of the production parameters permits the production of a crack- and pore-free material that achieves a density of over 99.5 percent. In addition, the parameters determined were transferred to a second laser beam melting system in a targeted manner in order to guarantee that the parameters and the state of the material are not influenced by the system.

In the next step, process parameters are developed for the case-hardening steel 17CrNi6-6. In parallel, test specimens for material investigations and heat treatment of the 20MnCr5 will be produced. Special attention is paid to the characterization of a possible anisotropy of the material due to the layered structure of the material.

Design criteria and their implementation in gear teeth are examined in the DFG project »Integral Lightweight Design of Gears«. The project (IGF: 20568BG) is funded for 24 months by the AiF Arbeitsgemeinschaft industrieller Forschungsvereinigungen "Otto von Guericke" e.V.