Assessment of Nano-Indentation Method in Mechanical Characterization of Heterogeneous Nanocomposite Materials Using Experimental and Computational Approaches

Abstract

This study investigates the capacity of the nano-indentation method in the mechanical characterization of a heterogeneous dental restorative nanocomposite using experimental and computational approaches. In this respect, Filtek Z350 XT was selected as a nano-particle reinforced polymer nanocomposite with a specific range of the particle size (50 nm to 4 µm), within the range of indenter contact area of the nano-indentation experiment. A Sufficient number of nano-indentation tests were performed in various locations of the nanocomposite to extract the hardness and elastic modulus properties. A hybrid computational-experimental approach was developed to examine the extracted properties by linking the internal behaviour and the global response of the nanocomposite. In the computational part, several representative models of the nanocomposite were created in a finite element environment to simulate the mechanism of elastic-plastic deformation of the nanocomposite under Berkovich indenter. Dispersed values of hardness and elastic modulus were obtained through the experiment with 26.8 and 48.5 percent average errors, respectively, in comparison to the nanocomposite properties, respectively. A disordered shape was predicted for plastic deformation of the equilateral indentation mark, representing the interaction of the particles and matrix, which caused the experiment results reflect the local behaviour of the nanocomposite instead of the real material properties.

An Energy-Based Concept for Yielding of Multidirectional FRP Composite Structures Using a Mesoscale Lamina Damage Model

“…The ever-increasing use of advanced polymer composites such as fiber-reinforced polymer (FRP) composites, nanocomposites, etc., as high strength-to-weight ratio and high-stiffness structural materials in advanced industrial applications [1][2][3], presents a unique design challenge with highly anisotropic material responses of the composites [4][5][6][7][8][9]. The FRP composites are essentially brittle with no plastic deformation, thus adequately described using a bilinear stress-strain curves with elastic and softening responses.…”

The effects of posterior cruciate ligament rupture on the biomechanical and histological characteristics of the medial collateral ligament: an animal study

“…The maximum loading load and displacement of the MCL were recorded. (3) The nanoindentation experiment was conducted as follows: the method used was the same as that described in a previous study [18]. In short, the MCL specimens of 24 experimental rabbits were cut parallel to the longitudinal axis with a frozen microtome, placed on a homemade slide, and fixed on the stage of the ultra-nanoindentation instrument.…”

Optimum Design of Sunken Reinforced Enclosures under Buckling Condition

“…The geometric models of the desired compartments with real dimensions were prepared by CATIA software and assembly of reinforcements in different directions. Afterward, ABAQUS software was used to simulate the structures using the finite element method, in which a mesh process was performed automatically using quadrilateral elements (cube with square cross-section) [28][29][30]. To reduce the computational cost and solution time, the response sensitivity analysis to mesh size was evaluated [31][32][33], and a mesh size of one millimeter was selected to continue the research.…”