All-Materials-Inclusive Flash Spark Plasma Sintering

TL;DR

This paper introduces a versatile ultra-rapid spark plasma sintering method applicable to a wide range of materials, enabling fast, homogeneous densification and shape control, with potential for energy-efficient mass production.

Contribution

The development of a universal flash spark plasma sintering technique that works across diverse materials regardless of electrical resistivity, with detailed simulation and experimental validation.

Findings

Successful densification of metals and ceramics within 8-35 seconds.

Homogeneous microstructures achieved across different materials.

Finite element simulation confirms rapid, uniform heating in samples.

Abstract

A new flash (ultra-rapid) spark plasma sintering method applicable to various materials systems, regardless of their electrical resistivity, is developed. A number of powders ranging from metals to electrically insulative ceramics have been successfully densified resulting in homogeneous microstructures within sintering times of 8-35 s. A finite element simulation reveals that the developed method, providing an extraordinary fast and homogeneous heating concentrated in the sample's volume and punches, is applicable to all the different samples tested. The utilized uniquely controllable flash phenomenon is enabled by the combination of the electric current concentration around the sample and the confinement of the heat generated in this area by the lateral thermal contact resistance. The presented new method allows: extending flash sintering to nearly all materials, controlling sample shape by an added graphite die, and an energy efficient mass production of small and intermediate size objects. This approach represents also a potential venue for future investigations of flash sintering of complex shapes.