Title of article :
Analysis of thermoelastic characteristics for vertical-cracked thermal barrier coatings through mathematical approaches
Author/Authors :
Go، نويسنده , , Jaegwi and Jung، نويسنده , , Yeon-Gil and Kim، نويسنده , , Seokchan and Paik، نويسنده , , Ungyu، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2011
Pages :
6
From page :
1615
To page :
1620
Abstract :
Thermoelastic characteristics of thermal barrier coatings (TBCs) with vertical cracks were analyzed through mathematical approaches to investigate the thermoelastic behaviors of TBCs in a service temperature. TriplexPro™-200 system was applied to prepare the relatively dense TBC using METECO 204NS powder. The microstructure of top coat in the TBC was just controlled to create vertical type cracks by reheating without powder feeding in same equipment and rapid cooling process. A couple of governing partial differential equations were derived based on the thermoelastic theory, and a finite volume model was developed to the governing equations to evaluate the thermoelastic characteristics, such as temperature distribution profile, displacement, and stress, inducing a thermal fatigue. For the specimen with two or more vertical type cracks, smaller displacement appears to longitudinal direction and larger displacement to radial direction as the number of crack increases. In the longitudinal stress distribution profiles to z-direction, the tensile stress at the interface between the bond coat and the substrate converts into the compressive stress when the specimen has vertical cracks more than two, while larger magnitude undulation develops for the specimen with smaller number of crack in the radial stress distribution profiles. The results obtained demonstrate that multiple vertical cracks enhance the thermal durability and extend the lifetime of TBCs.
Keywords :
Air plasma spray , Thermal barrier coatings , Vertical type crack , Thermoelastic characteristics
Journal title :
Surface and Coatings Technology
Serial Year :
2011
Journal title :
Surface and Coatings Technology
Record number :
1825318
Link To Document :
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