Predicting final stage sintering grain growth affected by porosity. (September 2020)

• Record Type: Journal Article
• Authors: Kerbart, Gabriel; Manière, Charles; Harnois, Christelle; Marinel, Sylvain
• Is Part Of: Applied materials today. Volume 20(2020)
• Publication Date: 2020-09
• Subjects: Grain growth -- Sintering -- Microstructure development -- MgAl2O4 -- Mechanisms -- Modeling; Materials science -- Periodicals; Materials -- Research -- Periodicals; 620.1105
• DOI: 10.1016/j.apmt.2020.100759
• Languages: English
• ISSNs: 2352-9407

Abstract

Highlights: Grain growth modeling in the final stage of sintering Transition grain growth mechanisms from high to low porosity Modeling porosity influence on grain growth transition region in final stage Abstract: Grain growth has a definitive impact on the quality of transparent sintered materials in areas such as ballistics, biomaterials, jewelry, etc. Controlling the sintering trajectory at the precise moment of final stage sintering is one of the main sintering challenges for obtaining high-performance, fully-dense nano-ceramics. However, the final stage of sintering involves a very complex coupling between the rate of porosity elimination/grain growth and transition mechanisms. This complexity makes predicting the sintering trajectory very difficult, and most transparent material production escapes this problem by using expensive high-pressure methods such as hot isostatic pressing (HIP). In the quest for a pressureless transparent material process, this paper addresses the challenge of predicting grain growth in the transition domain from the grain growth onset (in a high porosity region) to full density for MgAl2 O4 spinel. We present a comprehensive modeling approach linking theoretical models such as Zhao & Harmer's and Olevsky's equations to accurately predict the complex grain growth transition region of final stage sintering. This modeling approach opens up the possibility for numerical exploration of microstructure development via underlying kinetics experimental identification. Graphical abstract: Modeling sintering final stage microstructure development with influence of porosity and transition of mechanisms. Image, graphical abstract