Fundamental Aspects of Spark Plasma Sintering: I. Experimental Analysis of Scalability

Abstract

Scalability experiments on the spark plasma sintering (SPS) of similarly shaped alumina specimens of the four different sizes are conducted. The utilized experimental methodology, based on the principle of rigorous proportionality of all the specimen and tooling dimensions, employs two different SPS devices of different scales. The processed specimens are characterized in terms of relative density and grain‐pore structure. Overall, SPS shows good scalability potential within a single SPS device, but indicates substantial structure changes when switching between different SPS devices. Despite deviations in some cases, by and large, the experimental results obtained for different tooling sizes and temperature regimes are rather similar for specimens processed by the same SPS device. The obtained density and grain size spatial distributions are relatively uniform. High final densities with moderate grain growth are common. At the same time, due to the demonstrated possibility of a significant size impact in case of high heating rates and large specimen sizes, as well as the demonstrated differences of the processing outcomes based on different SPS devices, the predictive capability of reliable modeling approaches is of great importance for the industrial implementation of SPS techniques.

Fundamental Aspects of Spark Plasma Sintering: II. Finite Element Analysis of Scalability

“…In the present work, utilizing the developed thermo‐electro‐mechanical finite element framework, we assess shrinkage and grain growth kinetics as well as the temperature, porosity, and grain size gradients in the volume of alumina powder cylindrical specimens of four different sizes subjected to SPS. The results of modeling are compared with experimental data described in a companion article …”

Localized Overheating Phenomena and Optimization of Spark-Plasma Sintering Tooling Design

“…A finite element model developed based on the COMSOL™ platform for an SPS scalability study [35,36] has been considered and adapted to the considered overheating problem, therefore focusing the analysis on the tooling instead of the specimen; and underway, providing the utilized modeling framework with a more comprehensive description of the electric-thermal finite-element module.…”

Field‐Assisted Sintering Technology/Spark Plasma Sintering: Mechanisms, Materials, and Technology Developments

“…[13,256] Recently, more complex geometries have been presented in the literature. [257][258][259] In many cases, the sintering behavior is neglected and the material under consolidation is considered as a dense, elastic body. This can induce large errors in terms of stress level (a sintering materials being a viscous fluid).…”