PhD (M/F) Nano-porous silicon-elastomer hybrid: Mechanical properties assessed by laser ultrasonics.

Organisation/Company

CNRS

Department

Institut Langevin

Research Field

Physics

Researcher Profile

First Stage Researcher (R1)

Country

France

Application Deadline

1 Apr 2024 – 23:59 (UTC)

Type of Contract

Temporary

Job Status

Full-time

Hours Per Week

35

Offer Starting Date

2 May 2024

Is the job funded through the EU Research Framework Programme?

Not funded by an EU programme

Is the Job related to staff position within a Research Infrastructure?

No

Offer Description

This doctoral thesis is part of a Franco-German research project entitled “Nano-porous silicon-elastomer hybrids: from liquid-crystalline functionalization to tunable elasticity assessed by laser ultrasonics”, conducted in collaboration with the Hamburg University of Technology. (Institute for Materials and X-Ray Physics).

The PhD student will be at Institut Langevin.

Nano-porous silicon offers novel functionalities in various fields. The aim of the project is to develop a hybrid material with controllable elastic properties. To this end, a liquid-crystalline elastomer (LCE) will be confined within the pores of a nano-porous silicon membrane (pSi) . Given that the mechanical properties of LCE significantly change depending on stimuli [1], it is expected that this hybrid material will possess tunable properties. The idea is to combine the rigidity of the silicon matrix with the adaptability of the elastomer to ultimately propose various electromechanical devices, such as actuators or sensors. A Laser ultrasonic technique will be used to evaluate the elastic behaviour of this hybrid material. This technique involves generating mechanical waves through the thermo-elastic conversion of a laser pulse and detecting them using laser interferometry [2]. During this PhD, measurements will be performed on silicon membranes with different porosities, in particular to understand the impact of the porous network on material anisotropy. The feasibility of such measurements was demonstrated in a study conducted on pSi membranes with 50% porosity [3]. Elastic waves will then be observed in pSi membranes loaded with elastomer. The effective elastic properties of these membranes will be evaluated by combining guided wave modelling and an inverse identification procedure developed in parallel [4].
These works should provide a better understanding of the mechanical properties of confined viscoelastic materials as well as of the influence of pore morphology on wave propagation.

Requirements

Research Field

Physics

Education Level

PhD or equivalent

Languages

FRENCH

Level

Basic

Research Field

Physics

Years of Research Experience

None

Additional Information

Website for additional job details

https://emploi.cnrs.fr/Offres/Doctorant/UMR7587-CLAPRA-003/Default.aspx

Work Location(s)

Number of offers available

1

Company/Institute

Institut Langevin

Country

France

City

PARIS 05

Geofield

Where to apply

Website

https://emploi.cnrs.fr/Candidat/Offre/UMR7587-CLAPRA-003/Candidater.aspx

Contact

City

PARIS 05

Website

http://www.institut-langevin.espci.fr/

STATUS: EXPIRED