论文信息 - Modelling of austenitising with non-constant heating rate in hypereutectoid steels

Modelling of austenitising with non-constant heating rate in hypereutectoid steels

The calculation of distortion during heating for quench hardening needs an accurate modelling of the austenitising process. In dilatometer tests with constant heating rates, the parameter of a transformation model, which is based on a Johnson-Mehl-Avrami equation, can be determined in a simple manner. Whether the model and the transformation parameters are also valid for austenitising with non-constant heating rates is tested in this work. For this purpose, dilatometer tests were conducted with a change in heating rate during the transformation process of the hypereutectoid steel AISI 52100 (EN 100Cr6). With transformation parameters, which have been determined from austenitising with constant heating rates, the experimental and the calculated strain show no sufficient correlation during continuous heating with a non-constant heating rate. Transformation parameters have to be adjusted to get a good agreement between experiment and simulation.

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