Sökning: "Plastically deformed layer"

Hittade 2 avhandlingar innehållade orden Plastically deformed layer.

  1. 1. Degradation of railway rails from a materials point of view

    Författare :Martin Schilke; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Anisotropy; White etching layer; Rail grade; Rolling contact fatigue; Three dimensions; Plastically deformed layer; Railway Rail; Crack;

    Sammanfattning : From time to time railway rails need to be replaced. In that case and when new track is built, a decision has to be made about which rail grade that is going to be installed. The intention of this work was to compare different rail steels concerning their suitability from a mechanical durability perspective. LÄS MER

  2. 2. Rolling Contact Fatigue of Railway Rails with Emphasis on Crack Initiation

    Författare :Jonas Ringsberg; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; variable amplitude; crack closure; rolling contact fatigue; crack propagation; railway rails; damage accumulation; critical plane approach; crack initiation; plasticity; multiaxial fatigue;

    Sammanfattning : Increased traffic density and the heavier axle loads of modern trains have led to severe problems with rolling contact fatigue (RCF) which cause initiation of surface cracks in railheads. In this thesis, a specific type of surface crack, the head check, is studied numerically with emphasis on fatigue crack initiation. LÄS MER