Modelling of the stresses around a crack loaded by induction heating

In this research, the aim is to determine thermal stresses along a crack formed in an interface between a substrate and its coating using induction heating process. It is well known that developing accurate life prediction methods for coatings makes safe usage of coatings possible in industrial applications. Therefore, controllable thermal heating is needed for cyclic thermal loading in experiments.In induction heating process, an alternating voltage applied to the induction coil produces an alternating magnetic flux, which produces an alternating voltage at the same frequency with the current of the coil. The time-varying electro-magnetic field induces the eddy current, which generate a flux opposite to the direction of the coil flux. The eddy current then produces heat by the Joule effect. This heating process is accurately simulated by using finite element method.In this thesis, thermal and stress analysis along a crack between coating and substrate exposed to induction heating were done by using Ansys finite element analysis software. The analysis is performed in two steps. In the first step, couple electromagnetic-thermal analysis was done using Ansys solution loop written in APDL language. The resulting temperature history was used in uncouple structural analysis. Finally, stress distribution along the crack was determined.