Căutare Fascicula VIII după Data publicării

Afișează articolele 101-120 of 160

    • Experimental Study of Friction Losses in Ball Screws 

      Bălan, Rodica Mihaela; Urzică, Ana (Universitatea ”Dunărea de Jos” din Galați, 2009)
      In contrast with conventional sliding lead screws, ball screws with rolling friction between the screw and nut have high efficiency, accurate positioning and smooth, quiet operation at low friction that make this kind of ...

    • Tribological Characteristics and Formation of Subsurface Structures of Cast FE-CR-C Alloys with Different Content of Copper, under Sliding Friction 

      Novytskyy, Viktor; Lakhnenko, Volodymyr (Universitatea ”Dunărea de Jos” din Galați, 2009)
      Effect of copper contents (0%, 0.4%, and 14%) and modes of heat treatment on initial structure of Fe-Cr-C alloys (C~1.2%, Cr = 17…19%) and subsurface structure of friction layers and tribological characteristics of these ...

    • Tribological Testing Programs for Uhmwpe Matrix Composites 

      Chiculiță, Simona; Rîpă, Minodora; Andrei, Gabriel (Universitatea ”Dunărea de Jos” din Galați, 2009)
      This paper aims to review the knowledge on materials and tribology of the ultra high molecular weight polyethylene (UHMWPE) composites. The various mechanisms proposed for the wear behaviour of UHMWPE are closely associated ...

    • Fatigue Sensitivity Analysis of a Ship Structural Detail 

      Chirică, Ionel; Giuglea, Ștefan; Beznea, Elena-Felicia (Universitatea ”Dunărea de Jos” din Galați, 2009)
      In the paper, a FEM analysis used for fatigue assessment, based on the rules, was done. The approach for fatigue assessment in the early design stage of the ship structure has been developed. To overcome the challenges due ...

    • Rapeseed Oil Flammability on Hot Surface 

      Deleanu, Lorena; Ciocan, Sorin; Șolea, Liviu (Universitatea ”Dunărea de Jos” din Galați, 2009)
      The paper presents the tests and results upon rapeseed oil flammability on hot surface. The oil samples were obtained from a rapeseed oil after a dewaxing process. There were established temperature ranges for which the ...

    • Fabric Reinforced Filled Epoxy Composites 

      Bria, Vasile; Cîrciumaru, Adrian; Bîrsan, Iulian-Gabriel; Ungureanu, Victor (Universitatea ”Dunărea de Jos” din Galați, 2009)
      Among composites, the polymer matrix ones are the cheapest and the easiest to form but they show major disadvantages such as poor electrical and thermal conductivity, low fire resistance etc. In the case of any composite, ...

    • Measuring the Residual Stress of the Injection Moulded Polymeric Parts 

      Niță, Alexandra; Leițoiu, Bogdan; Goanță, Viorel; Bârsănescu, Paul (Universitatea ”Dunărea de Jos” din Galați, 2009)
      The residual stresses are usually introduced during manufacturing, and are caused by processes such as molding. This paper presents how the authors determine the residual stresses for the flat plates from ABS, PP and PS ...

    • Torsional Analysis of Ship Hull Model 

      Chirică, Raluca; Mușat, Sorin Dumitru; Boazu, Doina; Beznea, Elena-Felicia (Universitatea ”Dunărea de Jos” din Galați, 2009)
      In this paper a new methodology (numerical and experimental) proposed to analyze the ship hull torsion is treated. The torsion analysis is performed on a scale model (1:50) of a container ship, made of composite material. ...

    • Clay/Epoxy Composites 

      Cîrciumaru, Adrian; Bîrsan, Iulian-Gabriel; Bria, Vasile; Postolache, Ion (Universitatea ”Dunărea de Jos” din Galați, 2009)
      Fillers are generally used to decrease the costs of a composite material but they are changing also some of composite’s properties due to their physical properties, their dimensions and their shapes. Filled polymer could ...

    • Preliminary Results on the use of Palm Oil and Shea Butter in Lubrication Process in Food Industry 

      Bike Mbah, Jean Baptiste; Kamga, Richard; Gheorghieș, Constantin; Praisler, Mirela (Universitatea ”Dunărea de Jos” din Galați, 2009)
      In this study, vegetal oils (palm oil and shea butter) are analyzed for their uses in lubrication of mechanical part of machines in food industry. These vegetal oils were analyzed by X-ray diffraction and transmission ...

    • Structure Assessment by X-Ray Difractometry for Ceramic Materials used in Oral Prosthetic Systems 

      Ursache, Maria; Armencia, Oana (Universitatea ”Dunărea de Jos” din Galați, 2009)
      The paper presents a difractometric analysis on two types of ceramics nowadays available on the market and frequently used in restorative dentistry: InLine (IVOCLAR) and Hera-Ceram (HAEREUS KULZER). The diffractograms ...

    • A Fast Numerical Method to Predict Elastic Fields Due to Eigenstrains in an Isotropic Half-Space PartII. Program Validation and Simulations 

      Spânu, Sergiu; Dearn, Emanuel (Universitatea ”Dunărea de Jos” din Galați, 2009)
      A fast algorithm to solve the inclusion problem for arbitrarily shaped eigenstrains is validated in this paper. Influence coefficients formulas and numerical predictions for elastic fields due to a spherical region of ...

    • Postbuckling Behaviour of Composite Plates with Imperfections 

      Beznea, Elena-Felicia; Chirică, Ionel; Das, Purnendu K. (UDJG, 2010)
      The aim of the work presented in this paper is to analyze the influence of the imperfections on the changes in the buckling behaviour of ship deck plates made of composite materials. Thus, parametric analysis of the ...

    • Monitoring the Influence of Thermomagnetic Treatment on the Ion Nitrided Layer Using Microhardness Curves, for 42MOCR11 Steel Grade Case 

      Papadatu, Carmen-Penelopi (UDJG, 2010)
      Each of the stages of heat treatment in magnetic field (AC or DC) influences the hardness and durability of different steels. This influence is extended in the case of the measured microhardness values obtained in the ...

    • A Three-Dimensional Elastic-Plastic Analysis of Rolling Contacts 

      Benchea, Marcelin; Crețu, Spiridon (UDJG, 2010)
      An analysis model has been developed to model the nonlinear strain rate dependent deformation of rolling bearing steel stressed in the elastic-plastic domain. The model is designed in the frame of the incremental theory ...

    • The Influence of the Sintering Atmospheres on the Wear Behaviour of the Copper Based Alloys 

      Gheorghe, Ștefan; Teișanu, Cristina; Merstallinger, Andreas; Ciupitu, Ion (UDJG, 2010)
      The Powder Metallurgy (PM) technique allows manufacturing the sintered selflubricating materials having a high wear resistance. It is well known that the small and medium sized bearings are processed by PM with better ...

    • Surface Roughness Parameters Evolution Under Fatigue Loading 

      Mereuță, Valentin V.; Palaghian, Liviu C. (UDJG, 2010)
      The main objective of this paper is to demonstrate that in order to have a complete characterisation of fatigue degradation it is necessary to analyze the evolution of surfaces roughness, which can become a stress ...

    • Power Losses Estimation in Precessional Gear 

      Bostan, Ion; Dulgheru, Valeriu; Bodnariuc, Ion (UDJG, 2010)
      Having established the estimation relations of power losses in basic kinematical joints, it becomes relatively simple to establish the estimation relation of kinematical precessional transmission efficiency which, on the ...

    • The Reliability of the Rlac Bore-Hole Pumps 

      Drumeanu, Adrian Cătălin; Antonescu, Niculae Napoleon (UDJG, 2010)
      The paper aims to present a study concerning the determination of the borehole pumps operating reliability. The considered bore-hole pump for this study is RLAC 2 7/8 x 1¾ in x 32c type and it equips the oil-wells of ...

    • Numerical and Experimental Investigations Upon Articular Cartilage Mechanical Hysteresis 

      Frunză, Gheorghe; Ciornei, Florina (UDJG, 2010)
      The paper presents biomechanical and tribological considerations upon articular cartilage. The experimental in vitro results from static and dynamic contact tests are presented together with numerical modelling of the ...