R. Braun, BURGDORF GmbH & Co.KG, Stuttgart, Germany

Summary: Reducing dimensional changes during heat treatment by optimising the process with particular emphasis on quenching parameters Dimensional changes during heat treatment affect quality and require extra cost for grinding, straightening and sometimes even scrap. It is well known that reasons why distortion occurs are manyfold, most of them being related to part geometry and steel grade, hardenability and microstructure. Moreover there is the influence of the heat treatment process and, as a part of it, the quenching process, even if it is relatively small. In the report the main parameters for dimensional changes during heat treatment are presented. Based on practical results, it is shown that it is mandatory to have a close look on the complete manufacturing chain and how quenching technology can be optimised in order to safely reduce dimensional changes to a minimum.