Measurements of elastic modulus and fracture toughness of an air plasma sprayed thermal barrier coating using micro-cantilever bendingShow others and affiliations
2019 (English)In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 374, p. 12-20Article in journal (Refereed) Published
Abstract [en]
The elastic modulus and fracture toughness of an air plasma sprayed thermal barrier coating (APS TBC) were measured using the micro-cantilever bending technique. The micro-cantilevers were machined by a focused ion beam with their central arms either parallel or normal to the bond coat/topcoat interface. Such orientations allowed direct measurements of both the in-plane and out-of-plane elastic moduli as well as mode I fracture toughness by bending. The calculated elastic modulus along the in-plane and out-of-plane direction is 144 GPa and 110 GPa, respectively, suggesting that the APS TBC is elastically anisotropic at microscale. The derived mode I fracture toughness along the plane parallel to the interface is 0.40 MPam. This relatively low toughness reflects the weak fracture resistance of the highly-flawed APS for short cracks at microscale. The measurements in this study can be incorporated into micromechanical life time prediction models of the APS TBCs. © 2019 Elsevier B.V.
Place, publisher, year, edition, pages
2019. Vol. 374, p. 12-20
Keywords [en]
Elastic moduli; Ion beams; Microstructure; Nanocantilevers; Plasma jets; Plasma spraying; Thermal barrier coatings, Air plasma sprayed thermal barrier coatings; Direct measurement; Lifetime prediction; Measurements of; Micro-cantilevers; Micro-mechanical; Mode-i fracture toughness; Out-of-plane direction, Fracture toughness
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
URN: urn:nbn:se:hv:diva-14455DOI: 10.1016/j.surfcoat.2019.05.031ISI: 000486360000002Scopus ID: 2-s2.0-85066829982OAI: oai:DiVA.org:hv-14455DiVA, id: diva2:1356397
2019-10-012019-10-012020-01-30Bibliographically approved