The fracture toughness of 90 kg/mm2 chromium rail steel (TM-STM-22)

Fracture toughness tests on a sample of 90 kg/mm2 rail showed that it is strain rate sensitive. Its dynamic fracture toughness is below that of B.S.11 rail which may reduce the critical defect sizes to values less than those normally found in B.S.11 rails. This should be given serious consideration...