Ceramic sintering and properties characterization based on solid mechanics

H. Camacho Montes, Y. Espinosa Almeyda, J.D. Gamboa Garay, L.E. Barraza de León, A. Vega Siverio, I.M. Espinoza Ochoa, J.A. Otero Hernández, R. Rodríguez Ramos, B.J. Mederos Madrazo, F.J. Sabina, R.K. Bordia
Universidad Autónoma de Ciudad Juárez,
Mexico

Keywords: solid mechanics, homogenization, effective properties, EBSD, sintering, densification, ceramics

Summary:

Ceramic processing can be tedious and time-consuming. Several techniques have been developed to face these complex processing. One of the most popular techniques relies on different approaches for Design of Experiments and/or statistical process control. However, solid mechanics offers a considerable potential to describe the polycrystal structure – properties relationship as well as the densification and deformation during sintering. In the present work, the estimation of effective properties for polycrystal is developed based on a homogenization technique applied to a representative volume element (RVE) with the help of Finite Element Method (FEM). Applying this model, the effect of the crystallographic texture on the ceramic properties can be estimated considering the interaction at grain boundaries, which provide a more realistic analysis of the material properties. As an example, it is shown a RVE build from Electro Backscattering Diffraction (EBSD) and the overall properties are connected with pole figure. As a second example, densification and deformation is described during sintering. Constitutive laws for this kind of problem have been a topic that has attracted the researcher attention for decades. These laws include the effect of densification as well as some structural parameters as grain growth. FEM simulation allows to obtain maps to describe the density, stress, and deformation distribution in order to have a better characterization of macroscopic deformation during sintering. The viscous parameter that describes sintering can also be obtained from a sinter forging unit and considered for the simulation process. This could be more direct way to characterize sintering for a constrained system, for example, a bilaminar layer where high stresses can be developed at the interphase. These examples show how helpful can be solid mechanics to characterize ceramics materials.