Recent progress of cold sintering process on functional ceramic materials

Traditionally ceramic materials are fabricated at high temperatures (> 1000 ℃) by classical sintering techniques such as solid state, liquid phase and pressure-assisted sintering. Recently, a novelty cold sintering process (CSP) is widely developed to prepare ceramics and ceramic-based composites at incredibly low temperatures (≤ 300 ℃), providing new options for reducing the energy consumption during the ceramics manufacture. In this work, we review the processing features and possible densification mechanisms of CSP and its application in advanced functional ceramic materials, such as ZnO-based ceramics, piezoelectric ceramics, microwave dielectric ceramics, electrolytes ceramics, multilayer ceramics, and their composites. CSP creates a new opportunity to design grain boundaries and develop new types of functional ceramics and ceramic-polymer composites among material combinations that previously had incompatible processing windows. The work presents the viability of CSP as a competitive and sustainable alternative to other high-temperature sintering techniques.