Cutting edge materials technology in yet another awarded PhD of MEMC

On 19April 2016, Maria Strantza, MeMC-VUB PhD candidate, publicly defended her PhD thesis dissertation entitled “Additive Manufacturing as a tool for Structural Health Monitoring of metallic structures: Fatigue response and residual stresses”.

But what is Structural Health Monitoring and Additive Manufacturing?

The structural health monitoring (SHM) technology is developing smart and intelligent systems to continuously evaluate the integrity of structures. The task of the SHM system is to work as autonomous multi-disciplinary system in real applications without jeopardizing the function of the structure. Most of the industrial sectors are interested in SHM systems, especially aerospace and automotive.

Additive manufacturing (AM) has been characterized as the onset of the third industrial revolution. Conventional machining subtracts material to produce a structure and thus always uses more material than needed. On the contrary AM builds the material by melting metal powder through laser and provides an almost unlimited degree of freedom for the design of a structure. Thus, it enables light-weight and cheap structures, complicated designs and environmental friendliness.

How are these combined? A novel approach for SHM systems was developed at Vrije Universiteit Brussel based on the above technologies. The effective structural health monitoring (eSHM) system, as it is called, detects cracks in AM structures by means of an integrated network of capillaries which is embedded in the structure and built by AM technology.  When a crack propagates into the capillary, it creates a channel through which air rushes into the capillary increasing the pressure.

Maria points out: “My thesis investigates the feasibility of the eSHM system in Titanium and steel components. During this investigation the fatigue behaviour of the AM components with the eSHM system was validated. Furthermore, special attention was given in the material characterization of AM specimens – residual stresses and the internal defects like porosity”.

The PhD and the scientific work were supervised by Prof. Dr. ir. Danny Van Hemelrijck MeMC and  Prof. Dr. ir. Patrick Guillaume, MECH.

 Members of the committee were:

Prof. Dr. ir. Isabelle Vandendael - Vrije Universiteit Brussel, SURF

Prof. Dr. ir. Rik Pintelon - Vrije Universiteit Brussel, ELEC

Prof. Dr. ir. Lincy Pyl - Vrije Universiteit Brussel, MeMC

Prof. Dr. ir. Dimitrios Aggelis - Vrije Universiteit Brussel, MeMC

Prof. Dr. Helena Van Swygenhoven-Moens - Paul Scherrer Institut (PSI) and ´Ecole Polytechnique

F´ed´erale de Lausanne (EPFL), Switzerland

Prof. Dr. ir. Christopher Truman - University of Bristol, UK

 

Dr. ir. Marleen Rombouts - Vlaamse Instelling voor Technologisch Onderzoek (VITO)

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