Publications by Alberto Ortona

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials Part-III: Experimental verification of conversion products and infiltration depth by infiltration of Si-Zr alloy into mixed SiC/ graphite preforms

Ludger Weber, Alberto Ortona, Manoj Kondibhau Naikade, Caroline Hain, Annapaola Parrilli

Porous carbonaceous preforms, made from graphite and silicon carbide (SiC) powders, with varying graphite powder mass fractions and particle sizes, were infiltrated at 1500 degrees C and 1700 degrees C by Si-8 at. pct Zr alloy to produce dense Si-Zr-SiC co ...

ELSEVIER SCI LTD2023

Multi-configuration evaluation of a megajoule-scale high-temperature latent thermal test-bed

Sophia Haussener, Maurizio Barbato, Selmar Rudolf Binder, Alberto Ortona, Nithin Mallya, Clemens Gregor Suter

Thermal energy storage via latent heat provides an energy dense solution and, during discharge, a hot stream at a well-defined temperature. Utilizing metal phase change materials (PCMs) and high-temperature operation might enable fast (dis)charging and app ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials. Part II: Experimental verification of modelling approaches by infiltration of Si-Zr alloy into idealized microchannels

Ludger Weber, Giovanni Bianchi, Alberto Ortona, Manoj Kondibhau Naikade, Caroline Hain

In this work, the mechanisms leading to the pore closure in reactive melt infiltration (RMI) of carbon by pure silicon and a near eutectic Si-8 at-pct Zr alloy at 1500 and 1700 degrees C under vacuum were studied. Various geometrical configurations of micr ...

ELSEVIER SCI LTD2022

Liquid metal infiltration of silicon based alloys into porous carbonaceous materials. Part I: Modelling of channel filling and reaction phase formation

Ludger Weber, Alberto Ortona, Manoj Kondibhau Naikade

A relation for an adequate pore fraction needed to obtain residual Si and C free composites via reactive Si-X alloy infiltration is presented. The volume ratio of SiC and carbonaceous phase, the composition of the infiltrating liquid and the apparent densi ...

ELSEVIER SCI LTD2022

Pressure Drop and Convective Heat Transfer in Different SiSiC Structures Fabricated by Indirect Additive Manufacturing

Sophia Haussener, Maurizio Barbato, Ehsan Rezaei, Alberto Ortona

The microstructure of porous materials has a significant effect on their transport properties. Engineered cellular ceramics can be designed to exhibit properties at will, thanks to the advances in additive manufacturing. We investigated the heat and mass t ...

ASME2020

Design and optimization of a high-temperature latent heat storage unit

Sophia Haussener, Maurizio Barbato, Ehsan Rezaei, Alberto Ortona

High-temperature latent heat thermal energy storage systems offer compact storage solutions, benefiting from the large latent heat of phase change materials. Common challenges in their design process are the low thermal conductivity of the phase change mat ...

2019

Studying the wettability of Si and eutectic Si-Zr alloy on carbon and silicon carbide by sessile drop experiments

Ludger Weber, Alberto Ortona, Manoj Kondibhau Naikade

The contact angles of two different systems, molten silicon and a eutectic Si-8 at. pct Zr alloy and their evolution over timeon vitreous carbon and polycrystalline silicon carbide (SiC) substrates were investigated at 1500 degrees C under vacuum, as well ...

ELSEVIER SCI LTD2019

Early-stage oxidation behavior at high temperatures of SiSiC cellular architectures in a porous burner

Sophia Haussener, Ehsan Rezaei, Alberto Ortona

Early stage oxidation behavior of SiSiC cellular lattices with different cell types was studied at 1400 degrees C in two different environments: a porous burner and an electric furnace with stagnant air. Oxidation and silicon alloy bead formation were obse ...

Elsevier2016

Phase Change Material Systems for High Temperature Heat Storage

Sophia Haussener, Ehsan Rezaei, David Yann Samuel Perraudin, Selmar Rudolf Binder, Alberto Ortona

Efficient, cost effective, and stable high-temperature heat storage material systems are important in applications such as high-temperature industrial processes (metal processing, cement and glass manufacturing, etc.), or electricity storage using advanced ...

2015

Computing effective properties of random heterogeneous materials on heterogeneous parallel processors

Jean-Philippe Thiran, Tiziano Leidi, Alberto Ortona

In recent decades, finite element (FE) techniques have been extensively used for predicting effective properties of random heterogeneous materials. In the case of very complex microstructures, the choice of numerical methods for the solution of this proble ...

Elsevier2012