An air plasma spray process has been used to apply a model tri-layer Yb2SiO5/Al6Si2O13/Si environmental barrier coating system on SiC test coupons. Significant differences in the thermal expansion of the component layers resulted in periodically spaced mud cracks in the Yb2SiO5 and Al6Si2O13 layers. Upon thermal cycling between 1316°C and 110°C in a 90% H2O/10% O2 environment flowing at 4.4 cm/...

Receptor tyrosine kinase (RTK) signaling through Ras influences many aspects of normal cell behavior, including epithelial-tomesenchymal transition, and aberrant signaling promotes both tumorigenesis and metastasis. Although many such effects are cellautonomous, here we show a non-cell-autonomous role for RTK-Ras signaling in the delamination of a neuroblast from an epithelial organ. The C. ele...

We study delamination in a sandwich panel due to transient finite plane strain elastic deformations caused by local water slamming loads and use the boundary element method to analyze motion of water and the finite element method to determine deformations of the panel. The cohesive zone model is used to study delamination initiation and propagation. The fluid is assumed to be incompressible and...

Gao, Zhenyuan MSAA, Purdue University, May 2015. Comprehensively Simulating the Mixed-Mode Progressive Delamination in Composite Laminates. Major Professor: Wenbin Yu. Delamination, or interlaminar debonding, is a commonly observed failure mechanism in composite laminates. It is of great significance to comprehensively simulate the mixed-mode progressive delamination in composite structures bec...

A systematic study of factors affecting the delamination energy release rate and mode mix of a thermal barrier coating attached to a substrate is presented accounting for the influence of thermal gradients combined with rapid hot surface cooling. Transient thermal gradients induce stress gradients through the coating and substrate, which produce overall bending if the substrate is not very thic...

An attempt is made to analyse the effect of variation in thermal properties in Fibre Metal Laminate with an implanted delamination. This work focuses to explore the variations in thermal contrast for the increase in values of thermal properties of delamination, Aluminium layers and glass reinforced epoxy layers. The paper projects the numerical investigations towards the thermal analysis of fib...

This paper deals with the parallel simulation of delamination problems at the mesoscale by means of multi-scale methods, the aim being the Virtual Delamination Testing of Composite parts. In the non-linear context, Domain Decomposition Methods are mainly used as a solver for the tangent problem to be solved at each iteration of a Newton-Raphson algorithm. In case of strongly non linear and hete...

A specific device has been set up to test by vibration resonance the mode I fatigue delamination growth onset of composite laminates. This test system, based on the DCB test specimen, is a mass-spring-specimen dynamic system designed to resonate. The defined operating conditions allow performing delamination propagation tests under imposed load and stopping the test under reproducible condition...

In this study, a multi-spot laser scanning thermography (MLST) system is developed for automated, rapid and long-range inspection of delamination in composite structures. First, thermal waves are generated by scanning a multi-spot laser beam over a target composite structure, and the corresponding thermal waves are measured by using an infrared (IR) camera. Then a thermal image processing algor...