Microstructure-based damage and fracture modelling of alumina coatings

Semi-analytical analysis of thermally induced damage in thin ceramic coatings

“…Influence of temperature on damage evolution near interface for various types of initial distribution of damage for case of titanium-alloy (solid curves) and tungsten (dashed curves) substrates. finite elements for three studied types of alumina coatings (Silberschmidt, 2002) and provides quantitative information on both damage distribution and critical temperature that could be experimentally measured (Zhao and Silberschmidt, 2005). The next stage of the study is to analyze the effect of manufacturing-induced anisotropy of alumina coating on damage evolution, which is essential for the case of the tungsten substrate (Figs.…”

“…It can be implemented using the modified finite-element procedures with an account for damage evolution. Such implementation is rather cumbersome and should be based on the models accounting for the damage parameter either in a parametric form or with use of special finite elements with an additional degree of freedom (see models and respective discussions in (Silberschmidt, 2002;Zhao and Silberschmidt, 2005)). To overcome this complicacy and to obtain an effective solution algorithm, this paper utilizes a new, alternative approach based on the substitution of the finite-element solution with an analytical solution of the interim thermoelasticity problem for the bodycoating system at each iteration step of a general computational iterative procedure.…”

“…This approach was modified in Silberschmidt, 2003) where a computational scheme for estimation of damage evolution in bulk ceramics with different types of random microstructure is suggested. Application of this approach to a general case of thermally loaded brittle coatings presupposes numerical modeling, and respective algorithms are discussed in (Silberschmidt, 2002;Zhao and Silberschmidt, 2005). Such a cumbersome procedure to estimate parameters of the damage evolution process as well as stress, strain and temperature fields can be simplified (and enhanced) by incorporation of an analytical solution of the appropriate interim boundary-value problem of thermoelasticity into the scheme, thus resulting in an analytico-numerical approach (Shevchuk and Silberschmidt, 2003).…”

Deformation and Strength Parameters of a Composite Structure with a Thin Multilayer Ribbon-like Inclusion

“…One of the frequently used variants of FGM arrangement is the combination of ceramics with metal [36,37], but this often leads to the violation of the contact between them. Due to the brittle nature of ceramics, there is a need for additional research into the applicability limits of such FGM structures [38][39][40]. The complexity of the geometry of structural elements and consideration of imperfections in the contact of their components stimulate the process of improving mathematical models of FGMs to ensure their qualitative design both in terms of mechanical strength [12][13][14][41][42][43][44][45][46][47][48][49][50][51][52][53][54] and in terms of consideration of thermal, magnetic, piezoelectric loading factors [47,48].…”

Effect of the Transverse Functional Gradient of the Thin Interfacial Inclusion Material on the Stress Distribution of the Bimaterial under Longitudinal Shear

“…Many structural materials contain numerous thin inhomogeneities in the form of inclusions of different origins [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. Quite often, these inclusions are used as elements to reinforce the structural parts of machines and structures or as fillers in composite materials or coatings [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. The use of nanocomposites with specific properties in engineering and technology has significantly shifted the interest from the study of objects at the macro level (100–10 −1 m) and micro level (10 −3 –10 −6 m) to the nano level (10 −9 m) [ 16 , 17 , 18 , 19 , 20 ].…”