A sustainable society requires durable materials and material systems, in which the damage and failure mechanisms that act at the microscale are understood and controlled.
Johan Hoefnagels is an Associate Professor in the Eindhoven University of Technology (TU/e) group Mechanics of Materials at Mechanical Engineering, following his earlier background in applied plasma physics and advanced optical diagnostics. His current research focuses on experimental micromechanics of ‘thin films and interfaces’, by studying the systems’ micro-mechanics through integration of mechanical-microscopic characterization of underlying micro-mechanisms, such as damage and fracture, and integrate coupling of numerical simulations to experimental procedures. Topics of particular interest include delamination, ductile damage, size effects, flexible and stretchable electronics and MEMS. One of Johan’s research projects involves investigating a revolutionary mechanism to make electronics extremely stretchable and demonstrating this by means of an inflatable, in-vivo ultrasound detector, for which the first key step has been achieved: a free-standing interconnect has been designed that can be elastically stretched beyond 2000% and cyclically stretched at 1000% for over 10 million times.
Johan Hoefnagels obtained his MSc and PhD in Applied Physics at TU/e, with a PhD thesis on advanced optical diagnostics of surface processes during thin film deposition. After his PhD he made a dramatic switch to become assistant professor in ‘experimental micromechanics’ at the department of mechanical engineering, where he later became associate professor in the same field. He leads the ‘Multi-Scale lab’ dedicated to ‘integrated mechanical testing’, which is one of TU/e’s 10 strategic labs. Till 2018, Johan has (co-)authored ~75 journal publications (of which ~45 times as corresponding author) and >100 refereed proceedings/book contributions. At international conferences, has given >100 presentations, of which around a third on invitation, and organized 10 symposia. He has built up >2 years of international research experience during international visits to, amongst others, IMEC (Leuven, Belgium), SUNY (Albany, USA), NIST (Gaithersburg, USA), CSM (Golden, USA), and Harvard University (Cambridge, USA). And he holds, among others, the positions of Associate Editor of scientific Journal ‘Strain’ (impact factor 1.7) and Dutch representative of the European Structural Integrity Society.
Demonstrating the potential of accurate absolute cross-grain stress and orientation correlation using electron backscatter diffractionScripta Materialia (2019)
Ferrite slip system activation investigated by uniaxial micro-tensile tests and simulationsActa Materialia (2018)
Retardation of plastic instability via damage-enabled micro-strain delocalizationJournal of Materials Science (2015)
Copper–rubber interface delamination in stretchable electronicsScripta Materialia (2010)
Processing induced size effects in plastic yielding upon miniaturisationJournal of the Mechanics and Physics of Solids (2008)