Influence of phase interface properties on mechanical characteristics of metal ceramic composites

Abstract

The paper reports on theoretical study to elucidate the influence of geometric (width) and mechanical characteristics of phase interfaces on strength, ultimate strain, and fracture energy of metal ceramic composites. The study was performed by computer simulation with the movable cellular automaton method and a well-developed mesoscale structural composite model that takes explicit account of wide transition zones between reinforcing inclusions and the matrix. It is shown that the formation of relatively wide ceramic inclusionsbinder interfaces with gradual variation in mechanical properties allows a considerable increase in the mechanical properties of the composite. Of great significance is not only the interface width but also the gradient of mechanical properties in the transition zone. The presence of defects and inclusions of nano-and atomic scales in interface regions can increase internal stresses in these regions, induce a steep gradient of mechanical properties in them, and hence decrease strain characteristics and fracture energy of the composite.

Temperature Dependence of Mechanical Properties and Plastic Flow Behavior of Cast Multicomponent Alloys Fe20Cr20Mn20Ni20Co20-xCx (x = 0, 1, 3, 5)

“…The above-described deformation behavior of the heterophase material is due to the difference in elastic moduli of austenite and carbide (G = 80-85 GPa for FeCrMnNiCo [25] and G ≈ 140 GPa for M 23 C 6 [26] in the temperature range 77-300 K), so that the FeCrMnNiCo-5C alloy under loading behaves like a dispersion-reinforced metal-matrix composite with the compliant austenitic matrix and rigid carbide inclusions [27,28]. In such materials, rigid inclusions act as stress concentrators, which, even at low macroscopic loads, can cause significant distortion of stress fields around inclusions and plastic deformation of the compliant plastic matrix already at the initial stages of deformation (well below the macroscopic yield stress) [27,28]. At late plastic flow, they can activate slip systems with nonmaximum Schmid factors [29].…”

Overcoming the limitations of distinct element method for multiscale modeling of materials with multimodal internal structure

“…The simplest way of implicitly taking into account these factors is to change (increase) the inclination angle of the interpolation line in Fig. 10, as compared to the inclination angle of the ''basic'' interpolation line (obtained with regard to the influence of only secondary carbide phase nanoparticles) [72]. Notice that the increase in the inclination angle effectively reflects an increase in the concentration of impurities and lattice defects and a corresponding growth of local internal stresses.…”

“…The results of the performed uniaxial compression and threepoint bending tests on submicron-sized specimens have allowed us to estimate the characteristic values of the inclination angle of the interpolation line in Fig. 10 and to determine the mechanical parameters of distinct elements belonging to different transition zone areas [72]. This provided a basis for the study of how the phase interface width influences the integral mechanical characteristics of the metal-ceramic composite in three-point bending.…”

Voxel and Finite Element Modeling of the Ceramic–Polymer Composite Panel for Ballistic Impact Description

“…Earlier author, as well as other researchers, has used rather complex material models, such as Johnson-Holmquist model for ceramics and toughened adhesive polymer model for polymer [14,15]. Generally, such selection is rational, especially for ceramics as it destructs under cracks nucleation and influence of matrix-particle interface properties [16]. However, application of these models for composite on the base of ceramic grains may cause computational complexity.…”