TY - JOUR
T1 - Rolling contact fatigue in relation to rail grinding
AU - Steenbergen, Michaël
PY - 2016/6/15
Y1 - 2016/6/15
N2 - Spalling defects of a periodic nature are sometimes observed on heat-treated pearlitic steel rails. Defect properties suggest a relationship between maintenance grinding on a regular basis and the initiation of rolling contact fatigue (RCF). In this work, the effects of maintenance grinding are investigated experimentally for both standard and heat-treated pearlitic rails. Results show essentially different behaviour for both steels. On standard grades, friction-induced martensite (FIM) generated during grinding delaminates when in service. However, grinding induces severe top-layer deformation which coincides with that induced by train operation, thus yielding 'pre-fatigue' of the rail. On heat-treated grades, portions of FIM accumulated at groove edges during grinding are pressed into the deeper pearlitic matrix in combination with severe plastic deformation under tangential wheel-rail contact stresses. That process results in severe and extensive crack initiation. According to quantitative test results reported in the literature, this initial condition yields a reduction of the normal RCF life by roughly a factor nine, which is in accordance with both observations in the field and in the literature on rail spalling defects.
AB - Spalling defects of a periodic nature are sometimes observed on heat-treated pearlitic steel rails. Defect properties suggest a relationship between maintenance grinding on a regular basis and the initiation of rolling contact fatigue (RCF). In this work, the effects of maintenance grinding are investigated experimentally for both standard and heat-treated pearlitic rails. Results show essentially different behaviour for both steels. On standard grades, friction-induced martensite (FIM) generated during grinding delaminates when in service. However, grinding induces severe top-layer deformation which coincides with that induced by train operation, thus yielding 'pre-fatigue' of the rail. On heat-treated grades, portions of FIM accumulated at groove edges during grinding are pressed into the deeper pearlitic matrix in combination with severe plastic deformation under tangential wheel-rail contact stresses. That process results in severe and extensive crack initiation. According to quantitative test results reported in the literature, this initial condition yields a reduction of the normal RCF life by roughly a factor nine, which is in accordance with both observations in the field and in the literature on rail spalling defects.
KW - Rail grinding
KW - Rail spalling
KW - Residual stress
KW - Rolling contact fatigue (RCF)
KW - Squat
KW - White etching layer (WEL)
UR - http://www.scopus.com/inward/record.url?scp=84962148627&partnerID=8YFLogxK
UR - http://resolver.tudelft.nl/uuid:56124839-e7fc-492b-b501-3839daab1940
U2 - 10.1016/j.wear.2016.03.015
DO - 10.1016/j.wear.2016.03.015
M3 - Article
AN - SCOPUS:84962148627
SN - 0043-1648
VL - 356-357
SP - 110
EP - 121
JO - Wear
JF - Wear
ER -