Sökning: "white etching layer"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden white etching 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

3. 2. A study on wear characteristics of high strength steels under sliding contact

   Författare :Abdulbaset Mussa; Pavel Krakhmalev; Jens Bergström; Jens Hardell; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; High strength steels; thread joint wear; punch wear; sliding wear; surface cracking; reciprocal sliding; fatigue; surface delamination; white etching layer; nano-structured layer; friction; Materialteknik; Materials Engineering;

   Sammanfattning : In the last decades, significant improvements regarding the design, materials and technology of rock drills have been made. Likewise, in sheet metal forming, forming tools experience very high contact pressures when processing high strength steel sheets. LÄS MER

4. 3. Studies on the remineralization of white spot lesions : longitudinal assessment with quantitative light-induced fluorescence

   Författare :Susan Al-Khateeb; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : The global aim of this work was to develop and test the light induced fluorescence method using either laser light or a regular, i.e. noncoherent light source for quantification of mineral changes in white spot lesions. Validation studies were carried out to establish the correlation between fluorescence loss and mineral loss. LÄS MER

5. 4. Squat defects and rolling contact fatigue clusters - Numerical investigations of rail and wheel deterioration mechanisms

   Författare :Robin Andersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail surface irregularities; rolling contact fatigue clusters; dynamic vehicle–track interaction; rolling contact fatigue; studs; squats; fracture mechanics;

   Sammanfattning : Squat defects, a type of localised rolling contact fatigue damage appearing on rail surfaces with rail break as an ultimate consequence, have concerned infrastructure managers for the last couple of decades. In recent years similar types of defects—so-called studs—that are visually resembling squats, have started to appear. LÄS MER

7. 5. On the role of microstructure in wear of nanostructured carbide-free bainitic steels

   Författare :Pouria Valizadeh Moghaddam; Jens Hardell; Esa Vuorinen; Braham Prakash; Mikael Olsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tribology; Wear; Microstructure; Carbide-free bainite; Nanostructured; Retained austenite; Steel; High temperature; Machine Elements; Maskinelement;

   Sammanfattning : The significance of steel production for the development of sustainable society and economy is immense. Today’s fast growing global economy poses an increasing demand for improving the properties of steel. LÄS MER