Mechanical model for the interfacial thermal stress in porous ceramic foam coatings bonded to a substrate

Abstract

Coatings of porous ceramic foams have potential applications in thermal protection systems of space shuttles. This paper develops a mechanics model for evaluation of thermal stress of porous ceramic foam coating/substrate structures under thermal shock temperature variation. Numerical results show that interfacial stresses exhibit singularity at the edge of ceramic foam coating. Stress intensity factor will reduce when ceramic foam coating has a larger density or a larger thermal conductivity. Comparison between beam model and membrane model is made and it suggests that consideration of bending stiffness is essential for correct evaluation of the thermal stress in the ceramic foams.

Keywords:

• Porous ceramic foam
• coating
• transient thermal stress
• stress intensity factor

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by Innovation Fund of Shenzhen City of China (project Nos. JCYJ20170413104256729, JCYJ20170811160538023), the National Natural Science Foundation of China (project Nos. 11672084, 11602072, 11372086), and the Natural Science Foundation of Guangdong Province of China (project Nos. 2016A030311006, 2016A030310367).