Multi‐Scale Study of Sintering: A Review

Abstract

An integrated approach, combining the continuum theory of sintering with a kinetic Monte-Carlo (KMC) model-based mesostructure evolution simulation is reviewed. The effective sintering stress and the normalized bulk viscosity are derived from mesoscale simulations. A KMC model is presented to simulate microstructural evolution during sintering of complex microstructures taking into consideration grain growth, pore migration, and densification. The results of these simulations are used to generate sintering stress and normalized bulk viscosity for use in continuum level simulation of sintering. The advantage of these simulations is that they can be employed to generate more accurate constitutive parameters based on most general assumptions regarding mesostructure geometry and transport mechanisms of sintering. These constitutive parameters are used as input data for the continuum simulation of the sintering of powder bilayers. Two types of bilayered structures are considered: layers of the same particle material but with different initial porosity, and layers of two different materials. The simulation results are verified by comparing them with shrinkage and warping during the sintering of bilayer ZnO powder compacts.

Nanocrystal-enabled solid state bonding.

“…The easiness to obtain the numerical derivative for the Chebyshev polynomial completely justifies the extra step incurred. Moreover, the derivative produced in this way is less noisy than results obtained by the numerical derivation of the cubic spline [5].…”

“…Based on the availability of detailed microstructures for the evolution of the 3D compact, the sintering stress has been calculated following a similar method to the one described in [5]. All the quantities obtained from the microstructure are calculated in a sample volume: a volume occupying the core of the 3D specimen.…”

Towards 3D simulation of sintering processes

“…As regards the recent studies in modelling sintering processes [1][2][3][4], one can notice that it still remains difficult to deal with realistic particle arrangements systems. In fact, modelling of polycrystalline material sintering has only been handled in 2D [1,2].…”

Crossing the mesoscale no-man<U+2019>s land via parallel kinetic Monte Carlo.

“…Different numerical simulation methods have been used, including finite element methods [74], finite difference methods [62], discrete element methods [40] and kinetic Monte Carlo models [60]. As the physico-chemical and mechanical properties of the final piece are determined by the structure of the sintered body there is an interest in studying the microstructural evolution of the material.…”

“…The kinetic Monte Carlo simulation of sintering has been developed in recent years and analysis for simple configurations in 2D [78] have been extended to estimation of macroscale parameters [60] as well as simulations of 3D complex configurations [76,77]. This stochastic approach uses the Potts model to account for the local kinetics of the process, including grain growth, pore migration and vacancy diffusion and annihilation at grain boundaries.…”