Ever enlarging is the number of companies that are activated in the production of cement, plastic – rubber materials, optic fibbers, textiles, bio-textiles and metals. In the European Union more companies have become active in micro-nano electronics, in the automobile industry, in power plants, in aeronautics and photonics.
Ever more companies use materials under different conditions of assembly (welding, thermal treatment, cutting, fatigue etc).  All these companies, as much in their applications in the productive process as in the production of their final products, are using advanced materials such as magneto-elastic, piezo-electric, Nano-composites, thin films/coatings, semi-gels and gels, graded ceramics, textiles and bio-textiles. Most of these materials are not sufficiently characterized, with regard to their mechanical attributes and characteristics (elasticity, resistance, resistibility etc).  Particular problems appear in depth of time, related with the resistance in materials‘ fatigue. The high demand in new materials, in new coming applications and in new products, it comes at the expense of the accurate and sufficient characterization of attributes of materials.  The results are frequently unfavourable regarding the reliability and the life duration of the final products.

 The increasing use of new materials (mainly composites), their particularly complicated mechanical behaviour, their time dependence behavior and their interaction with the environment, require accurate, fast and sufficient estimation of their mechanical attributes and characteristics at their production stage, as well as at their application level. The proposed research innovations of NOVA MECHANICA are based on efficient scientific and technological knowledge that concern the proposed materials with their specific commercial applications.

 The core science  of  these technological innovations is based on the simultaneous collection, analysis and measurements of force, displacement and contact time of an indenter, where the Decoding of the experimental signals reveals the  mechanical attributes of the material that is under the observation of this innovative diagnostic process. Applications exist on electronics and metal materials, in large scale as well as in small scale (MEMS- NEMS, sensors, probes, PC hard disks).

  Our research led us to the analysis of the mechanical response of an indenter that come in contact with the surface of a material body and accordingly to the extraction of primary mechanic attributes of the material (e.g. Elastic modulus, Piezo-magnetic constants, angle of friction etc.) and their connection with intimately related physical and chemical attributes of the material (e.g. Molecular Weight, Composition of constituent materials etc.). The resulting Science concerning specific categories of materials (Elastomers, Piezo-magnetic materials, Cement) is original and pioneering.
The essential technological innovation is found in the methodology that is applied in the mechanical response (force, displacement, time, temperature, electric current, magnetic flux etc.) of the indenter (flat punch, sphere, cone, pyramid etc.) with known properties, at its contact with a flat surface of a material of unknown mechanic attributes. Consequently, the measured results from the Instrumented indentation are interpreted with the new diagnostic methodology and gives as result the ‘unknown’ mechanical attributes of the material. Moreover, it is proposed the modification of existing devices (e.g. Atomic Force Microscope–AFM) that can impress material imperfections and then appreciate their behaviour in the more general strength of material sense, in very small scales.  Immediate application is the imaging of magnetic domains in small-scale surfaces.

  We have investigated the quasi-static normal indentation of incompressible rubber-like substrates by sharp rigid cones. We found how to correlate rubber mechanical properties with the indentation response that is the relation between the applied force and the resulting vertical displacement of the cone’s tip. The effect of the angle of the cone was investigated, as well as the influence of surface friction and the initial restrain. The indentation response agrees remarkably well with available experimental results of instrumented indentation.

   Of particular technological importance are rubbers that are manufactured from latex and may have a wide range of additives (carbon, silica, oils, kaolin etc.). The elastic modulus of rubbers is inversely proportional to the average molecular weight. Whatever influences the molecular weight influences the elastic modulus. For example, when exposed to radiation, natural and synthetic rubber can undergo cross-linking and their average molecular weight increases inversely proportionally to the radiation dose.
Therefore, the elastic modulus increases with the radiation dose. Applications of rubber materials include tires, springs, bearings, membranes, blades, hoses, conveyor belts, seals, pipes, textiles etc and are used extensively in cars, aircrafts, seals, buildings, bridges, railroads, cables and medical equipments. We have recently extended the analysis to include fatigue estimates of rubber materials.

We have filed for two patents related to the indentation of rubber-like materials and biomaterials that are pending in the Greek Patent Office :
1) Pretension mechanism and method for the extraction of mechanical properties of elastomers, human and animal tissues, trough indentation  tests, ΟΒΙ:  20080100186/13-06-2008 .


 2) Modified indenter tip and method for the extraction of mechanical properties of elastomers, human and animal tissues, through  indentation tests, ΟΒΙ:  20080100187/13-06-2008 .


and we are planning to apply for European Patent protection, according to the European Law of patent priority .

  According to the above we propose the design of models of ‘diagnostic’ devices aiming at the qualitative control of the range of materials (plastics- rubbers, cement, piezo-magnetics / piezo-electrics and nano-coposites), as well as new design and analysis methodologies of composite and  visco-elastic materials. Our current technology, aims to cover the industries need and demand for materials’ quality control, as much in the production as in the materials applications, needs that are continuously increasing. Our services include the design and the optimization of quality control systems as well the undertaking of the research study of several complex technical issues (e.g. systemic damages in production lines, accidents, etc.).

  The operational advantage of our technology is its application on dimensions of objects that can be very small and that it can be used even for in-situ use in worksites and by low-trained construction teams.  The training of the use of the related diagnostic devices is simple and fast (in any case, we are available to provide this service). The technology can be applied in very small-scale objects, which can be extremely important for relevant cases (e.g. art-work, archeological findings etc.). The diagnostic devices can adjust easily in aggressive environments (e.g. toxic, radioactive environment). Finally, the material attributes’ identification procedure through the related measuring device is very fast.



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