Laboratory of Technology and Strength of Materials

Director: Pantelakis Spiros, Professor
Faculty members:
Apostolopoulos Charis, Associate Professor
Lampeas George, Professor
Kermanidis Theodoros, Professor
Pantelakis Spiros, Professor
Tserpes Konstantinos, Assistant Professor
Other Members:
Karvelis Stefanos, E.T.E.P.
Koutsoliakou Archontoula, Secretariat
Contact Details
Phone: (+30 2610) 969498
Fax: Laboratory of Technology and Strength of Materials Department of Mechanical Engineering and Aeronautics, University of Patras Campus, Rion, Patras, 26500
Website of the Laboratory: http://ltsm.mead.upatras.gr

Subject of the Laboratory of Technology and Strength of materials is the education of undergraduate and post-graduate students on science and on technology of materials, strength of materials and components of engineering structures, as well as conducting fundamental and applied research on the above scientific fields. Concerning education, LTSM offers courses specialized in science and technology of materials, mechanical behavior of materials, strength of materials and structural components, fracture mechanics, structural analysis and structural integrity.

Concerning research, LTSM performs high quality research on development and characterization of materials, strength evaluation of structural components, as well as analysis and design of  aeronautical structures. LTSM participates in a big number of national and European competitive research programs, mostly related to aeronautics, and has been established as focal point in Greece in terms of research on aeronautical materials and structures.

With reference to both education and research, LTSM has developed strong links with all leading Universities and aeronautics research centers in Greece and abroad, as well as all major aerospace and aircraft industries worldwide.

Finally referring to the sector of industrial services, LTSM affords equipment, human resources and long experience in mechanical testing, structural integrity mechanical behavior of materials and structures, structural analysis.


Teaching

LTSM provides the following cources:

 

Undergraduate studies:

1)     Materials science I,II

2)     Strength of materials I,II

3)     Mechanical behavior of materials

4)     Aeronautical materials

5)     Aeronautical structure analysis I,II

6)     Fatigue of aeronautical structures

7)     Fracture Mechanics

8)     Metallic structure analysis

9)     Analysis of limit loads

10)  Technology of polymer and composite materials

 

Post-graduate studies :

1)     Structural integrity

2)     State of the art technologies in Materials Science

3)     Advanced Strength of materials


Research

Recent activities of the Laboratory of Technology and Strength of Materials extend to the following scientific areas:

  • Science and technology of materials (development of new materials and their production technologies, materials characterization and certification, experimental characterization and simulation of the mechanical behavior of materials and structures),
  • Strength of materials and structural components (determination of strength of metallic and composite materials, nano- materials and structural parts made of the pre mentioned materials),
  • Structural analysis (stress analysis, evaluation of structural integrity and impact strength, structural optimisation),
  • Design of aeronautical structures based on damage tolerance
  • Fracture mechanics
  • Damage Mechanics

 

Research activities of LTSM spread in the whole range of mechanical engineering applications with emphasis on aeronautics. Research is mainly conducted mainly in the frame of European competitive research programs.

 

Recent programs :

  • Aeronautical Application of Wrought Magnesium (AEROMAG), CEC, STREP, 2005-2007.
  • Non-Linear Multiscale Analysis of Large Aero-Structures (MUSCA), CEC, STREP, 2005-2007.
  • Modular Joints of Aircraft Composite Structures (MOJO), EC, 2006-2009.
  • Cellular Structures for Impact Performance (CELPACT), EC, 2006-2009.
  • More Affordable Aircraft Through Extended, Integrated & Mature Numerical Sizing (MAAXIMUS), EU FP7, 2008-2013.
  • Simulation Based Solutions for Industrial Manufacture of Large Infusion Composite Parts (INFUCOMP), EU FP7, 2008-2013.
  • Cost Effective Reinforcement of Fastener Areas in Composites (CERFAC), EU FP7, 2010-2014.
  • Extended Non-Destructive Testing for Composite Bonds (ENCOMB), EU FP7, 2010-2014.
  • Innovative Manufacturing of Complicated Ti Components (INMA), EU FP7, 2010-2014.
  • Smart Aircraft in Emergency Situation (SMAES), EU FP7, 2010-2014.

 

Since 2002, LTSM coordinates the European Aeronautics Science Network (EASN). Subject of EASN is to support and upgrade the research activities of the European Aeronautics Universities, as well as to facilitate them to respond to their key role within the European Aeronautical research Community in incubating new knowledge and breakthrough technologies. Members of this network are Professors of the most significant Universities across Europe.

 

Research obtained at LTSM are published in peer review scientific journals and presented at international conferences. During the last decade more than 180 publications were made by LTSM members.

Recent puplications are:

  • K.I. Tserpes, P. Papanikos, G.N. Labeas, Sp.G. Pantelakis. Multi-scale modeling of tensile behaviour of carbon nanotube-reinforced composites. Theoretical & Applied Fracture Mechanic, 2008, 49, 51-60.
  • Sp.G.Pantelakis, Ch.V.Katsiropoulos, G.N.Labeas, H. Sibois ''A concept to optimize quality and cost in thermoplastic composite components applied to the production of helicopter canopies'', Journal of Composites: Part A (40), 2009, p.p. 595-606.
  • G. N. Labeas, Diamantakos, I., Kermanidis, Th.

Assessing the effect of residual stresses on the fatigue behavior of integrally stiffened structures. Theoretical and Applied Fracture Mechanics, 2009, 51(2), 2009, 95-101.

  • K.I. Tserpes, G.N. Labeas. 'Mesomechanical analysis of Non-Crimp Fabric Composite Structural Parts. Composite Structures, 2009, 87(4), 358-369.
  • Ll. Llopart P., Tserpes, K.I., Labeas, G.N.

Experimental and theoretical investigation of the influence of imperfect bonding on the strength of NCF double-lap shears joints. Composite Structures, 2009, 92, 1673-1682.

  • G. Moraitis and G. Labeas. Prediction of residual stresses and distortions due to laser beam welding of butt joints in pressure vessels. International Journal of Pressure Vessels and Piping, 2009, 86, 133-142.
  • A.N. Chamos, Sp.G. Pantelakis, V. Spiliadis.

Fatigue behaviour of bare and pre-corroded magnesium alloy AZ31. Materials & Design, 2010, 31, 4130-4137.

  • A.T. Kermanidis, A.D. Zervaki, G.N. Haidemenopoulos, Sp.G. Pantelakis. The influence of salt fog exposure on the fatigue performance of alclad 6xxx aluminum alloys laser beam welded joints. Journal of Materials Science, 2010, 45, 4390-4400.
  • A.N. Chamos, C.A. Charitidis, A. Skarmoutsou, Sp.G. Pantelakis. An investigation on the high stress sensitivity of fatigue life of rolled AZ31 magnesium alloy under constant amplitude fatigue loading, Fatigue & Fracture of Engineering Materials & Structures (FFEMS), 2010, 33, 252-265.
  • G.N. Labeas, M.M. Sunaric. Investigation on the static response and failure process of metallic open lattice cellular structures. Strain, 2010, 46(2), 195-204.
  • K.I. Tserpes, R. Ruzek, Sp. Pantelakis. ''Strength of Pi-shaped non-crimp fabric adhesively bonded joints'', accepted for publication in Plastics, Rubber and Composites Journal.

 

In recent years, LTSM has organized the following conferences :

 

  • 6th International Conference on Mesomechanics 2004, Patras 2004.
  • 3th National Conference of Metallic Materials, Patras 2007.
  • 1st International Conference of Engineering Against Fracture (ICEAF I), Patras 2008.
  • 2nd International Conference of Engineering Against Fracture (ICEAF II), Mykonos 2011.

 

During the last two decades, more than 20 doctorate thesies have been successfully carried out at LTSM.

Equipment

  • UNIVERSAL TESTING MACHINE 200kN: Displacement rate can be varied from 0.015 - 500 mm/min.
  • 2 FATIGUE TESTING MACHINES MTS (250kN & 100kN): Servo-hydraulic machines with frequency range up to 104 Hz suitable for fatigue testing under constant or variable load, for evaluation of characteristic fracture properties (KIC, COD) and for tensile tests under dynamic monotonic loading. The 250 KN machine is equipped with environmental chamber for testing at temperatures ranging from -100 to 400 0C.
  • TORSION/BENDING FATIGUE TESTING MACHINE (160kNm)
  • COMPRESSION TESTING MACHINE (2500kN): Suitable for testing construction materials and for structural components compression testing.
  • 4 CREEP MACHINES: Suitable for creep testing up to 1000 0C.
  • INSTRON IMPACT TEST MACHINE (Dynatup drop tower)
  • SPLIT HOPKINSON BARS: Suitable for high strain rate tensile and compression tests (>103/sec)
  • 2 MOBILE UNITS FOR STRAIN MEASUREMENTS
  • CHAMBER FOR ACCELERATED SALT SPRAY TESTS
  • EQUIPMENT FOR ACCELERATED CORROSION TESTS: a) immersion, b) alternate immersion, c) exfoliation corrosion
  • 4 STRESS CORROSION CRACKING DEVICES (in-house developed): the devices are equipped with automated system of alternate immersion.
  • HIGH RESOLUTION DIGITAL CAMERA OPTICAL SYSTEM FOR CRACK DETECTION AND CRACK MEASUREMENT: Suitable for crack growth measurements under monotonic and fatigue loading as well as for multi-site damage detection.
  • METALLOGRAPHY LABORATORY: optical microscope, mobile unit for digital stereoscopic capturing of fracture surfaces, grinding and polishing equipment).
  • HARDNESS AND MICROHARDNESS TEST MACHINES
  • NON-DESTRUCTIVE TESTING UNIT (C-SCAN, A-SCAN, acoustic emission, eddie current, potential drop)
  • MOBILE UNIT OF SURFACE TREATMENT (Ultrasonic Impact Treatment 27KHz)
  • PORTABLE SURFACE TREATMENT DEVICE ADJUSTABLE TO CNC (Ultrasonic Impact Machining)
  • PORTABLE DEVICE FOR RESIDUAL STRESS MEASUREMENTS (Open hole drilling)
  • EQUIPMENT FOR CRACK GROWTH MEASUREMENTS WITH REPLICATION TECHNIQUE (up to 10μm)
  • THERMAL TREATMENT CHAMBER (1100 0C)
MACHINE SHOP (1 Lathe, 1 CNC cutting machine)