Finite Element Analysis of Self-Healing and Damage Processes in Alumina/SiC Composite Ceramics

Abstract

Among various ceramic matrix composites developed, self-healing ceramics have been studied as new functional materials. Self-healing occurs in such materials by high-temperature oxidation triggered by a micro-crack initiation on the surface, and the strength of the material autonomously recovers to its robust state since the micro-crack is re-bonded. To facilitate the use of self-healing ceramics in machines and equipment, a novel numerical simulation method based on finite element analysis (FEA) needs to be applied. In this study, we applied a previously proposed constitutive model to a series of self-healing and damage processes. In the constitutive model, the damage process is formulated on the basis of fracture mechanics, while the self-healing process is formulated on the basis of empirical oxidation kinetics. The FEA model implemented the constitutive model to simulate a series of experiments of the alumina/15 vol% SiC composites. The self-healing process was targeted to a prescribed damage by Vickers indentation. Thereafter, the self-healing behavior was quantitatively compared with that observed in the experiment. The results suggest that the proposed FEA approach can be applied to the analysis of ceramic matrix composites with self-healing properties.

Self-healing by design: universal kinetic model of strength recovery in self-healing ceramics

“…To model the crack-gap filling behavior, the crack geometry, notably, V g ( Equation 3 ) and the area of one side of the fracture surface A ( Equation 7 ), must be evaluated. In general, both values are estimated using FEA based on the material properties and various damage conditions [ 51 – 54 ]. Many studies have experimentally evaluated the self-healing behavior of a Vickers crack [ 17 , 56 ].…”

“…Using Equations (11) and (12), the total V h under both isothermal and nonisothermal oxidations can be estimated, as implemented in our calculations. Equation (11) will be useful in future computational simulations for describing damage and healing behaviors, e.g., using the finite element method [51][52][53][54].…”

Finite element analysis of the fracture statistics of self-healing ceramics

“…Table 3 shows the distribution characteristics of the microstructure. These values are determined by referring to the previous studies [ 28 , 29 , 36 ]. Regarding the atmospheric conditions for the self-healing process, constant values of healing temperature T h and oxygen partial pressure were set.…”

“…In particular, the authors have proposed a continuum damage model that incorporates the effects of oxidation kinetics on the strength recovery rate of self-healing ceramics [ 28 , 29 ]. In addition, the proposed model was implemented in the finite element method (FEM) to demonstrate the numerical analysis of alumina/SiC particle composites under various conditions of temperature and oxygen partial pressure.…”

On Adaptive Control for Electrical Discharge Machining Using Vibroacoustic Emission

“…Nowadays, the use of ceramic products in the industry is continuously growing due to its excellent exploitation properties [15,16]. Plenty of scientists aim their study on the development of a new class of materials as conductive ceramic nanocomposites [17][18][19]. This kind of material should provide mechanical properties up to the level of continent ceramics or even exceed them, but also be suitable for electrical discharge machining.…”