INNOTRACK Deliverable D4.3.7, Innovative laboratory tests for rail steels – Final report

Report, 2009

This paper presents a first thorough investigation of different laboratory tests for rail materials combined with numerical simulations and metallographic investigations. A specific methodology for the latter is given in the Appendix. Laboratory tests for new rail materials are desirable supplements to field tests in order to save time and money. Thus, less valuable products can be early withdrawn from expensive field tests. Within this work package, test conditions for laboratory tests of rail materials have been defined and compared to field conditions. Existing test equipment and evaluation methods of the WP partners have been exploited for the laboratory tests in order to find out the applicability to the pre-defined field conditions. The tests were performed at the SUROS twin disk test machine, at the VAS linear full-scale test rig and at DB full-scale roller rigs. The results were compared among other with respect to metallography and material deterioration. Subsequent numerical calculations showed that the full-scale tests more or less deviate systematically from the expected contact conditions due to bending of wheel and rail. In addition, predictions regarding RCF have been carried out and compared to test results. It is shown that twin disk tests as well as tests on a full-scale linear test rig are suitable for practical use. The tests on full-scale roller rigs failed due to the need for specific rail samples, which ultimately destroyed the fixtures during the tests. An evaluation of the different tests including a rough estimate of effort is given.