Ausgewählte geförderte Forschungsvorhaben

The below research projected have been initiated during my appointment as Associate Professor at Stevens Institute of Technology, NJ, USA, during 2013-2017. I keep strong research collaborations with my collaborators in the below research programs while building up my research agenda at Hamburg University of Technology (TUHH).

Nano and Microstructured Metallic Composite Sections

Doctoral Student:
Majid Ramezani Goldyani, Stevens Institute of Technology, USA, mramezan@stevens.edu
PI/Project Lead:
Marcus Rutner, Hamburg University of Technology, Germany, marcus.rutner@tuhh.de
Collaborator:
Michael Demkowicz, Massachusetts Institute of Technology, USA, demkowicz@mit.edu

Multilayered metal nanocomposites have gained interest in science and industry due to their unique properties. Enhanced properties of these nanocomposites compared to conventional metallic materials, such as radiation damage resistance, electrical and magnetic properties, strength and indentation hardness, ductility, and fatigue resistance, make them attractive for novel applications. An essential step towards industrial usage of multilayered nanocomposites is to be able to joining them. However, conventional joining processes cause localized heating around the joint and may compromise the integrity of the nanolayered composite cross section. In this research, Cu-Nb multilayered nanocomposites are synthesized by dc magnetron sputtering at room temperature on Si substrate. Various joining processes are introduced and performed and the advantages and drawbacks in regard to the processing and the nanomechanics of the joint are discussed. The nanostructure of the sputter-deposited Cu-Nb joint zone and adjacent heat affected zone is investigated by Scanning Electron Microscope imaging. Further, the hardness and strength of the joint area is studied by Atomic Force Microscopy. Findings of this research have been published Scripta Materialia (please refer to my recent publications).

Photo right by City University of New York

                                              Internal Damage Detection of Micro Defects in Composites on Demand

Doctoral Student:
Behnoush Golchinfar, Stevens Institute of Technology, USA, bgolchin@stevens.edu
PI/Project Lead:
Marcus Rutner, Hamburg University of Technology, Germany, marcus.rutner@tuhh.de
Collaborateur:
Dimitri Donskoy, Stevens Institute of Technology, USA, ddonskoy@stevens.edu

Composite structural systems are becoming more and more widespread across industries and the capability to finding and tracking internal defects before they have grown to major deterioration is of paramount importance in regard to safety, economy and maintenance. We are exploring a novel method of internal damage detection and tracking in composite material using thermo-chemical sensing. A micro-size network of strings is interwoven into the composites. Each string consists of a pair of tubes, containing one of two different non-polar reactants. A local defect within the composites causes straining and cracking of the tube shell, resulting in direct contact of the two non-polar reactants. The latter undergo a chemical reaction resulting in a polar product. Our preliminary investigation shows that a polar product, when exposed to a microwave energy source, heats up dramatically in comparison to the ambient composite material or the non-polar reactants. This very localized thermal signature can be visualized by an infrared camera. The key characteristics of this embedded structural health monitoring technology is that it allows wide area monitoring and does not require embedded wiring or power source. Various types of composite materials with this structural health monitoring technology embedded are investigated experimentally and computationally. This paper sheds light on the physics enabling detection and monitoring, including the microwave heating and subsequent cooling of the composites material, and undertakes a sensitivity study of the technology. Further, findings of an extensive parametric study, targeting a prioritization of parameters, such as electrical and thermal conductivity, relative permittivity, relative permeability and heat capacity at constant pressure, are presented.

                                      Fiber Metal Laminate VS Monolithic Steel

PI/Project Lead:
Marcus Rutner, Hamburg University of Technology, Germany, marcus.rutner@tuhh.de
Collaborateur:
Calvin Rans, Delft University of Technology, Netherlands, C.D.Rans@tudelft.nl

In this research project comprises fundamental research on development of fiber metal laminates providing superior properties such as fatigue resistance. The following shows fiber metal laminates applied as patches on structural mild steel. The increase of fatigue resistance is 300% compared to monolithic steel. Computational results have been published in the AIAA Journal. More recent findings on experimental data of new fiber metal laminate composite layups are published in a forthcoming Journal article.

                                      Blast Vulnerability Prediction Capability of Steel and Composite Structures

PI/Project Lead:
Marcus Rutner, Hamburg University of Technology, Germany, marcus.rutner@tuhh.de
Collaborateur:
David Vaccari, Stevens Institute of Technology, USA, dvaccari@stevens.edu

The current state of research and engineering consulting in high-speed dynamics is that the highly nonlinear response of structural components when subjected to high energy blast loading can be quantified by either experimental testing or high-fidelity explicit finite element analysis. Both approaches, empirical studies and finite element analyses, are expensive and very time-consuming. There is research demand in development of a methodology which allows characterization of failure modes and quantification of nonlinear response behavior of structural components subjected to extreme loading in a very time-efficient but accurate way. This paper introduces a novel methodology to allow vulnerability assessment and response prediction capability of bride/lightweight bridge members and components subjected to impulsive loading within seconds of response time. The approach includes Multivariable Polynomial Regression (MPR) to build a response surface using data entries from a database comprising response data of members of various failure modes. The response surface is used to parameterize and optimize blast-resistant design and to enable a viable component shock quantification and qualification approach. This approach has been automated via the development of a graphical user interface (GUI) software tool and allows immediate on-site decisions on the vulnerability of structural and mechanical components subjected to direct and indirect impulsive loading. This novel software tool could be of value to agencies, manufacturer, designers and architects in various engineering fields, such as civil, naval, aerospace, mechanical engineering involved in high-speed dynamics. Results have been published in the International Journal of Protected Structures and in Engineering Structures.

                                              Damage Detection of Damage Precursors in Steel Components

Project Lead:
Marcus Rutner, Hamburg University of Technology, Germany, marcus.rutner@tuhh.de
Sophia Hassiotis, Stevens Institute of Technology, USA, shassiot@stevens.edu
Dimitri Donskoy, Stevens Institute of Technology, USA, ddonskoy@stevens.edu

In May 2016 we have got awarded a multi-year research grant from the NJDOT (New Jersey Department of Transportation) to explore methodologies to detect damage precursors in steel components. Our proposed methodology comprises damage detection through wide area scanning and answers the three main questions in structural health monitoring, i.e. where is the defect, what is the defect type and what is the defect growth rate. Stay tuned for upcoming publications.