A Comparative Study of Thermo-Mechanical Fatigue Performance of Different Grades of SiMo Nodular Cast Iron

This thesis is a comparative study of the Thermo-Mechanical Fatigue (TMF) performance of different grades of SiMo nodular cast iron for heavy-duty diesel engine exhaust gas manifold applications. The TMF performance of the current SiMo variant used to manufacture exhaust manifolds - SiMo 5.10 (C-3.25Si-4.45Mo-0.76), is compared with that of the...

Load sequence effects on fatigue crack growth: A variable amplitude fatigue model in the framework of the Thick Level Set method

Recently a new framework to predict fatigue crack growth has been developed based on the Thick Level Set method. The aim of this thesis is to extend this framework to allow for realistic loading spectra. First, a calibration method for this framework is presented. This method decouples crack growth, defined by a Paris like equation, from the...

Thermo-Mechanical Fatigue-Lifetime Determination of Diesel Engine Exhaust Manifolds

The start-up and shut-down cycling of a heavy-duty truck engine leads to temperature and mechanical strain variations in the exhaust manifold, subjecting it to thermo-mechanical fatigue (TMF) damage. For the automotive manufacturers, it is essential to accurately predict the TMF lifetimes of the exhaust manifolds under service conditions. The...