Prof. dr. Guido Janssen

Research interests

At this moment my research interests are twofold:

Combined abrasive and corrosive wear of aluminum and steel.

The research question stems from slurry transport in pipe lines. The steel of the pipes wears up to a millimeter per month.

We find that aluminum wears by forming a brittle oxide layer, which easily is removed by abrasive wear. Hence a much higher wear in sea water than in fresh water is observed.

For steel we find the counterintuitive effect that for combined abrasive and corrosive wear the wear in seawater is less than the wear in fresh water. We are in the process of explaining this effect. At the same time we’re confronting our combined abrasive corrosive wear experiments with slurry loop wear measurements. At this moment it is highly likely that combined abrasive corrosive wear is a too simple model for wear of slurry pipes.

Growth of graphene

Graphene was first isolated by Geim and Novoselov in 2004. They removed a single layer of carbon atoms from graphite by use of scotch tape. In 2009 the first graphene was grown from methane on a Nickel catalyst by chemical vapor deposition (CVD). Since then other metals and metal films have been used as catalyst, most notably copper. At this time the research centers around reducing the defect density in graphene. Both point defects as well as ripples form a serious problem in the application of CVD grown graphene.

Current research projects

Reduction of hydro-abrasive wear in the dredging industry, Yueting Liu, m2i.

Graphene waferscale technology, Cristina Varone, STW

Education

Together with dr. Marcel Sluiter I teach “Statics” to the freshmen of Mechanical Engineering, Maritime Technology, and Industrial Design. My “teaching philosophy” is: “Learning is practicing, guided by a professional”. Hence we have a small series of lectures, twice as much hours of exercise classes and lots of home-work, which will be discussed in a plenary session afterwards.

Some key publications

• Tensile stress in hard metal films, G.C.A.M. Janssen, A.J. Dammers, V.G.M. Sivel, W.R. Wang, Appl. Phys. Lett., 83, (2003), 3287-9.
• Stress in hard metal films, G.C.A.M.Janssen and J.-D.Kamminga, Appl. Phys. Lett.,85,(2004) p.3086-3088.
• Stress and strain in polycrystalline films, critical review, G.C.A.M. Janssen, Thin Solid Films, 515, (2007), 6654.
• Celebrating the 100th anniversary of the Stoney equation for film stress: Developments from polycrystalline steel strips to single crystal silicon wafers, G.C.A.M. Janssen, M.M. Abdalla, F. van Keulen, B.R. Pujada, B. van Venrooy, Thin Solid Films, 517, (2009) 1858.
• Graphene based piezoresistive pressure sensor, Shou-En Zhu, Murali Krishna Ghatkesar, Chao Zhang, and G.C.A.M. Janssen, Appl. Phys. Lett. 102, (2013) 161904.
• Ballistic transport in graphene grown by chemical vapour deposition, V.E. Calado, Shou-En Zhu, S. Goswami, K. Watanabe, T. Taniguchi, G.C.A.M. Janssen, and L.K.M. Vandersypen, Apl. Phys. Lett. 104, (2014) 023103.