Publications de Michael Stuer | EPFL Graph Search

Spark Plasma Sintering of Ceramics: From Modeling to Practice

Summarizing the work of nearly a decade of research on spark plasma sintering (SPS), a review is given on the specificities and key factors to be considered in SPS of ceramic materials, based on the authors’ own research. Alumina is used primarily as a mod ...

2020

Synthesis and Sintering of ZnO Nanopowders

Paul Bowen, Michael Stuer, Zhe Zhao

Nanopowders are continuously under investigation as they open new perspectives in numerous fields. There are two main challenges to stimulating their development: sufficient low-cost, high throughput synthesis methods which lead to a production with well-d ...

Mdpi Ag2017

Comparison of apparent activation energies for densification of alumina powders by pulsed electric current sintering (spark plasma sintering) and conventional sintering-toward applications for transparent polycrystalline alumina

Paul Bowen, Claude Paul Carry, Michael Stuer, Zhe Zhao

In the quest for high real in-line transmittances for transparent polycrystalline alumina (PCA), we need defect free processing. One of the biggest advances in producing high density defect free ceramics over recent years has been the advent of spark plasm ...

Materials Research Society2017

Toward Knowledge-Based Grain-Boundary Engineering of Transparent Alumina Combining Advanced TEM and Atomistic Modeling

Paul Bowen, Marco Cantoni, Michael Stuer, Cécile Hébert, Abhishek Tewari, Farhang Nabiei

Transition element dopants (e.g., Y, La) are commonly used as sintering aids in polycrystalline alumina ceramics, which segregate to the grain boundaries and control the grain-boundary mobility. However, due to the extremely thin (

Wiley-Blackwell2015

Influence of Y and La Additions on Grain Growth and the Grain-Boundary Character Distribution of Alumina

Paul Bowen, Michael Stuer, Zhe Zhao

Grain-boundary character distributions (GBCDs) were determined for spark plasma sintered Y- and La-doped aluminas prepared at temperatures between 1450 degrees C and 1600 degrees C. La doping leads to grain boundaries that adopt (0001) orientations 3.7 tim ...

Wiley-Blackwell2014

Colloidal Processing and Yield Stress Modeling Towards Dry Pressed Green Bodies for Transparent Polycrystalline Alumina

Paul Bowen, Michael Stuer

Colloidal processing is a key aspect in modern ceramic processing but most formulations are found empirically. The need for a better knowledge based design of suspension formulation can be achieved by using interparticle potential modelling linked to rheol ...

Wiley-Blackwell2014

Yield stress modelling of doped alumina suspensions for applications in freeze granulation: towards dry pressed transparent ceramics

Paul Bowen, Michael Stuer

Rheology of powder suspensions is a key factor in many processing routes, and better understanding of the parameters that control the rheology improves technical progress by reducing the empirical factors in the formulation of powder slurries. The strict r ...

2012

Freeze granulation: Powder processing for transparent alumina applications

Paul Bowen, Michael Stuer, Zhe Zhao

Use of freeze granulated powders is successfully used as an industrially viable alternative to loose powder sintering for transparent polycrystalline alumina (PCA). Freeze granulation with narrow granule size distribution was realized after suspension cond ...

2012

Transparent Polycrystalline Alumina : Processing, Sintering and Microstructural Analysis

Michael Stuer

Over the last century, the constant quest to improve the mechanical properties of ceramics has ultimately led to the appearance and production of transparent ceramics. Indeed, microstructural refinement and reduction of the residual porosity after sinterin ...

EPFL2012