INNOTRACK Deliverable D4.3.8, Innovative laboratory tests for rail steels

Report, 2009

There is a need for laboratory tests of rail material by railway opera-tors as well as by manufactures. The tests should represent oper-ational conditions for the rail material. They should allow withdraw-ing less valuable products from far more expensive field tests. This guideline is based on the experience from the WP4.3 partners with respect to laboratory tests for rail steels. As the operational demands on rail material may differ from site to site (with respect to the curvature etc.), a suitable preparation of the laboratory tests is necessary. It should start with a definition of the conditions to be tested, e.g. with a testing matrix. According to present knowledge, related tests can be done at twin disk test rigs or at specialized full-scale linear test rigs. Full-scale roller rigs are not recommended because the fixing of the samples is difficult and the preparation of the rail material requires a huge effort. After testing the wear, RCF and deformation should be evaluated in accordance with a consistent evaluation scheme. Metallographic in-vestigations could be applied especially with respect to quantifying material deterioration. The compliance with the pre-defined requirements should be moni-tored throughout the test since contact conditions may vary due to profile wear and specific test rig deviations. If such deviations occur, the test conditions should be re-evaluated through numerical simula-tions. Thus, the effect on the test results may be estimated. The results of testing on twin disk tests as well as those on a linear test rig can provide results suitable for practical use. An evaluation of the different tests including a rough estimate of effort is given.