A numerical study on interface crack growth under heat flux loading

Abstract

A numerical framework for the coupled thermo-mechanical analysis of crack growth in structures loaded by an applied heat flux is outlined. Using a thermo-mechanical cohesive zone model (TM-CZM), load transfer behavior is coupled to heat conduction across an interface and the corresponding interface crack. Nonlinear effects occur due to the coupling between the mechanical and thermal problem introduced by the conductance-separation response between crack faces as well as through the temperature dependence of material constants of the CZM. The description of the load transfer behavior uses a traction-separation law with an internal residual property variable that characterizes the extent of damage caused by mechanical loading. The description of thermal transport includes a representation of the breakdown of interface conductance with increase in material separation. The current state of interface failure, the presence of gas entrapped in the crack, the radiative heat transfer across the crack and a contact conductance between crack faces determine the cohesive zone conductance. The TM-CZM is implemented into a finite element code and applied in the study of interface crack growth between an oxidation protection coating on a thermal protection material.

A thermo-mechanical cohesive zone formulation for ductile fracture

“…which is similar to the model by Hattiangadi and Siegmund (2005) utilised for the simulation of delamination of carbon-carbon substrates subjected to a heat flux load. Finally, the interface temperature can be resolved locally within the interface using the energy equation of the interface in Eq.…”

Three-dimensional analysis of a cohesive crack coupled with heat flux through the crack

“…The crack in the domain under consideration is modeled by enriched approximations of displacements and temperature like in (21) and (22), respectively and the jumps in Eq. (24).…”

“…The thermodynamic foundations of the theory are covered for instance in [15][16][17][18]. Recent applications of thermomechanical model coupled with crack or damage can be found for example in [19][20][21][22][23]. In this paper a different approach to the problem is proposed.…”

FEM Study of Fatigue Crack Growth in a Power Semiconductor Chip Subjected to Transient Thermal Loading

“…The implemented TM-CCZM represents an extension of the cyclic CZM reported in (Bouvard et al, 2009) onto the case of transient thermal loading conditions. The thermal extension is realised by augmenting mechanical relations with relations for the heat flux across the cohesive zone (CZ), along similar considerations as proposed in (Hattiangadi and Siegmund, 2005) and (Oezdemir et al, 2010). To accelerate the fatigue crack growth (FCG) simulations, the implementation also contains a cycle jump technique based on direct iteration of the damage evolution equation, as proposed in (Ural and Papoulia, 2004).…”