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Mihai-Constantin Balaşa, Ştefan Cuculici, Cosmin Panţu, Simona Mihai, Alexis-Daniel Negrea, Mihai-Octavian Zdrafcu, Dorin-Dacian Leţ, Viviana Filip and Ştefan Cristea

Abstract

Designing orthopedic implants with a long lifespan is essential for improving patients’ quality of life. It is necessary to develop new products with a high degree of personalization for the human body. Physicians and engineers analyzed the geometry and behavior of healthy joints’ motion under specific load conditions as well as the behavior over time and lifetime of orthopedic implants fitted to patients to improve their quality. The paper presents the way in which three-dimensional modeling techniques using specialized software (Catia, SolidWorks) can be combined with reverse engineering techniques (3D scanning) to optimize the design of orthopedic implants. The design of an implant consists of its three-dimensional modeling, as well as simulation of its integration into the human body, in order to analyze its behavior during motion. Therefore, it is necessary not only to 3D model the parts that make up the implant itself, but also to 3D model the bone to which the implant will be fitted. The paper highlights the complementarity of the classic modeling techniques with the reverse engineering techniques, which is necessary because the design of the parts that make up the implant itself can be achieved by specialized software modeling techniques, while the bones, having complex geometries, are better suited to 3D Modeling by scanning.

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Elena Valentina Stoian, Maria Cristiana Enescu, Vasile Bratu, Carmen Otilia Rusanescu and Florina Violeta Anghelina

Abstract

Non/oriented electrical sheets are sheets tailored to produce specific properties and are produced from Fe-Si or Fe-Si-Al alloys. Non-oriented electrical steel sheets are incorporated into a wide range of equipment, from the simplest domestic appliances to hybrid and pure electric vehicles. In studying about the magnetic, there have a lot of method can be used for the different experiment requirement such as measuring magnetic flux, nominal loss and other objectives.

During electrical steel processing, there are usually small variations in both chemical composition and thickness in the hot-rolled material that may lead to different magnetic properties for the same steel grade. Therefore, it is of great importance to know the effects of such variations on the final microstructure and magnetic properties of these steels. The purpose of this work was to study microstructural changes of the bands investigated during processing occurring siliceous strips with non-oriented grains. The second aim was to study the influence of grain size on the total magnetic losses at 1.0 T and 1.5 T. Materials 10 rolls intended to be processed into quality electrical steel M400-50A (according to EN 100027-1) were analyzed with metallographic microscope Neophet 32 and the magnetic characteristics was made with Epstein frame according IEC 6040/4-2, with an exiting current frequency of 50Hz at 1.5T and 1.0T induction after aging treatment of 225°C for 24 hours. Sample for light microscopy observation were prepared by polishing and etching in 5% Nital.

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Ionel Rusa and Cornel Marin

, Clarence W. Boca Raton: CRC Press LLC, 2000 [6] Automated machinery maintenance – Bill Powel, Tony Burnet [7] Bearing vibration analysis – Connected Technology Center - Training modules [8] Ghidul analistului de vibrații – Costin Ciprian Ilie 2001 [9] Reliability –Centered Maintenance, Anderson R.T., Neri L., Elseivier Science Pubishing, London, England, 1990 [10] Quality and Reliability of Technical Systems, Birolini A., Springer – Verlag, Berlin, 1994 [11] Fiabilitatea, mentenabilitatea şi disponibilitatea sistemelor tehnice

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Liliana-Laura Badita, Gheorghe Gheorghe, Vasile Bratu, Valentin Gornoava, Marian Vocurek, Aurel Zapciu and Iulian Sorin Munteanu

/nanotribology, Boca Raton: CRC Press, 1999. [9] Binnig G., Quate C.F., Gerber Ch. Atomic Force Microscope, Physical Review Letters 1986; 56(9): 930-933. [10] http://www.ntmdt-si.com/modular-afm/prima [11] Despa V., Gheorghe Gh.I., Badita L.L., Aspects regarding the quality of surfaces obtained by using the Selective Laser Sintering Technology, The Scientific Bulletin of Valahia University - Materials and Mechanics 2015, 13(10): 133-137. 54

Open access

Vasile Bratu and Ileana Nicoleta Popescu

(4) (2011) , 81-84 . [7] A. Kemna, Better steel quality thanks to the solidification model, Metals & Mining International News, May 2001. [8] V. Bratu, C Mortici, C Oros, N Ghiban , Mathematical model of solidification process in steel continuous casting taking into account the convective heat transfer at liquid- solid interface, Computational Materials Science 94 (2014), 2-7. [9] Ya Meng and Brian G. Thomas, Heat Transfer and Solidification Model of Continuous Slab Casting : Con1D, Metallurgical and Materials Transactions B