Prof. D. Rittel

Faculty of Mechanical Engineering

Technion, 32000 Haifa, Israel

Abstract:

Adiabatic shear failure is a dynamic failure mechanism that results from the formation of a localized narrow band in which the shear strain concentrates and reaches very high values. An early and well accepted analysis of ASB formation relies on the competition between strain-hardening and thermal softening, so that when the latter overcomes the former, the material can no longer harden and fails by shear localization. Therefore, the role of thermally induced strain-softening is viewed as central in ASB formation.

We propose another approach to the phenomenon, based on the dynamically stored energy of cold work, the latter being identified as a key factor for the onset of shear localization. This energy affects and dictates the microstructural re-arrangements (dynamic recrystallization, twinning) occurring during dynamic deformation. In this talk, we will present experimental results on the evolution of the temperature and the microstructure of the dynamically sheared material, and a model describing its evolution.

These results will be discussed to propose another physical explanation to dynamic shear localization as a microstructure-related instability.

Prof. D. Rittel, Chair Professor of Mechanical Engineering, Technion, Israel Institute of Technology

RESEARCH INTERESTS

Mechanics and Materials. Fracture mechanics (static and dynamic, damage). Numerical (FEM) modelling of material / structural behavior. Thermomechanical couplings. Mechanical metallurgy. Failure analysis of materials/mechanical systems.

Geophysics. Mechanical and failure properties of volcanic magma at high ejection rates.

ACADEMIC DEGREES

1983-1988 Ph.D., Materials Science.

The Hebrew University of Jerusalem, The Graduate School of Applied Science and Technology.

1981-1983 M.Sc., Materials Science (with distinction).

The Hebrew University of Jerusalem, The Graduate School of Applied Science and Technology.

1975-1979 B.Sc., Materials Engineering (Specialization in Nuclear Engineering).

Ben-Gurion University of the Negev, Beer-Sheva, Materials and Nuclear Engineering epartments.

ACADEMIC APPOINTMENTS

Chair Catedra de Excellencia. University Carlos III, Dept. of Continuum Mechanics and Structures, Madrid, Spain. Sept 2011-2012.

Chair April 2009. Technion. The Zandman Chair in Experimental Mechanics

Chair Clark B. Millikan Visiting Professor in Aeronautics (08/ 2006- 08/2007)

California Institute of Technology, Graduate Aeronautical Laboratories,

Pasadena, CA.

Professor April 2006, Faculty of Mechanical Engineering, Technion, Israel Institute of Technology.

Associate Professor December 2000, Faculty of Mechanical Engineering, Technion, Israel Institute of Technology.

Senior Lecturer March 1997, Faculty of Mechanical Engineering, Technion, Israel Institute of Technology.

Lecturer February 1994, Faculty of Mechanical Engineering, Technion, Israel Institute of Technology.

EDITORIAL ACTIVITIES

August 2008 : Associate Editor, Mechanics of Materials.

May 2007 : Editorial Advisory Board, The Open Mechanics Journal.

March 2007 : Editorial Board Member, International Journal of Engineering Science.

July 2005 : Associate Editor, Experimental Mechanics.

AWARDS & DISTINCTIONS

2011 (July) Fellow, Society of Experimental Mechanics

2011-2012 Chair of Excellence (6 months), Universidad Carlos III, Madrid, Spain.

2009 Lt. Gen. A. Peled Research Fund for armor related subjects, Technion.

2009 The Zandman Institute Chair in Experimental Mechanics, Technion

2006-2007 Clark B. Millikan Visiting Professorship in Aeronautics, Caltech, USA.

2005 Lt. Gen. A. Peled Research Fund for armor related subjects, Technion.

2002 A. Goldberg Research Prize, Technion.

1988 Elected to represent Israeli research students at SAMPE European Chapter Conference, Milano, Italy.

1982 Fellowship in the memory of Professor A.S. Tetelman, HUJ.

March 8th 2012,9:30-10:30,1512#