YCN Industry in the Spot: Julie Devillard (Saint-Gobain Research Paris and MATEIS, Lyon)

After graduating from Grenoble INP Phelma with an engineering degree in materials science and engineering, I decided to continue my studies with a thesis. However, I wanted to keep a link with industrial research so I chose a CIFRE thesis.

The CIFRE program allows a company to be subsidized to hire a PhD student in for a partnership with a public laboratory. In my case, the subject was proposed by the company which chose a laboratory for the partnership and then selected a PhD student. The CIFRE thesis project is then validated and subsidized by the ANRT. In my case, this thesis was carried out with Saint-Gobain on the company side and the MATEIS laboratory of INSA Lyon on the university side. I had a supervisor at Saint-Gobain and two thesis co-supervisors at MATEIS.

Saint-Gobain Research Paris is the R&D center of Saint-Gobain, a multinational company that designs, produces and distributes materials mainly in the fields of housing and transportation. It is a company that devotes a significant part of its turnover to R&D and has many partnerships with the academic field, notably with CIFRE theses.

One of the problems encountered by Saint-Gobain, particularly in the plasterboard industry, is the lightening of plasterboard. This lightening presents many advantages in terms of reduction of grey energy, improvement of the working conditions of the installers and a reduction of costs. However, gypsum board must meet a number of requirements in terms of mechanical strength. The aim of my thesis was therefore to determine the link between the microstructure of the core of a lightweight gypsum wallboard and its compressive properties. 

For this I mainly used X-ray tomography which is a non-destructive 3D imaging technique very well adapted to the study of porous materials. This method is one of the specialties of the MATEIS laboratory, especially for the realization of mechanical tests in situ and is the main reason for the partnership with Saint-Gobain for this thesis. 

A CIFRE thesis therefore has the advantage of working in a laboratory with a high quality academic management but also to work on a concrete application. The PhD student must therefore make the link between the skills of the laboratory and the company. Moreover, as a CIFRE PhD student, I was employed by Saint-Gobain and therefore had access to the advantages that come with it, such as the works council or bonuses. This also allowed me to have a first experience in a company in addition to discovering the academic environment.

A possible difficulty may lie in the management of requests which may be different between the company and the laboratory. For example, the company will demand that the results be "industrially realistic" and the laboratory will push the PhD student to provide publishable results. There are sometimes difficulties to publish freely, in my case I didn't have any problem, only some information was confidential, it was only necessary to have all the communications validated by the company.

To conclude, I recommend the CIFRE thesis to those interested in continuing the research but staying close to the application.

Dr. Julie Devillard
Former CIFRE PhD student