Now showing items 23-35 of 35

    • Research Rearding of Composite Materials under the Influence of Abrasive Wear 

      Florea, Carmen; Florea, Alexandru; Chivu, Mioara (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The method described in the paper will allow estimating the composite materials performances with different structures and various working conditions, with a view to estimate useful life of technological equipments parts ...
    • Residual Stresses Effect on Fatigue Life of Rolling Contacts 

      Crețu, Spiridon; Benchea, Marcelin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The fatigue life tests carried out on two groups of ball bearings point out the positive influence of the compressive residual stresses induced by a previous loading in the elastic-plastic domain. The values of residual ...
    • Seizure of a High-Speed Three-Wave Journal Bearing 

      Buzescu, Daniela; Pascovici, Mircea (Universitatea ”Dunărea de Jos” din Galați, 2008)
      This paper is focused on the geometry and operating parameters of the bearing experimentally studied at NASA Glenn Research Center by F. Dimofte. It presents two simple thermoelastohydrodynamic (TEHD) models for two typical ...
    • Shear Stability as Oils’ Performance Indicator 

      Ciortan, Sorin; Rîpă, Minodora; Chiculiță, Simona; Spânu, Constantin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a comparative analysis between the shear stability tests results and four ball tests results for some industrial oils. This correlation is used for establishing the way how the mechanical solicitations ...
    • Some Aspects about Driving Wheel/Rail Contact in Steady State Interaction 

      Mazilu, Traian (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The driving wheel/rail steady state interaction and the response to harmonic excitation were studied using a complex model for track. The starting point for numerical simulations is the Green matrix of the track. The ...
    • Study of Wear Evolution for a Hydraulic Oil Using a Four Ball Tester 

      Spânu, Constantin; Rîpă, Minodora; Ciortan, Sorin (Universitatea ”Dunărea de Jos” din Galați, 2008)
      Time is crucial for the wear of materials. Time of an experiment must be long enough to obtain an observable wear but no so long to make the experiments expensive. For determining anti-wear properties of the hydraulic oils ...
    • Test-Rig for Pressure Measurements in an Aerostatic Bearing 

      Muscă, Ilie (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The paper presents a test rig for local pressure investigation in an aerostatic or gasostatic bearing system. Using a simple and performant computer assisted measurement device, pressure evolution in lubrication area can ...
    • The Effect of Wiberg Angle on the Contact Pressure Pistribution in Natural and Artficial Joint 

      Tudor, Andrei; Parsu, Carmen; Sorina, Opriș (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The analogies and differences between the mechanical joints and the biological ones, in the presence of relative motion, are based on the pressure distribution. The paper analysed a numerical model of the pressure distribution ...
    • The Influence of the Applied Load on the Friction Coefficient of the Sintered Iron-Base Bearings 

      Teișanu, Cristina; Gheorghe, Ștefan; Tudor, Andrei; Ciupitu, Ion (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In the recent years the iron base sintered bearings production was considerable increased at the expense of the copper based ones, due to the low cost and availability of the iron powders as well as the higher strength. ...
    • The Tool to Model through Micro Strain and Micro Cutting 

      Tache, Antonio; Tache, Carmen (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The cutter wear is analised by a single hard fixed particle (inclusion) in brittle material. The shakedown pressure of the inclusion contact is directly proportional to shear field stress of the cutter surface and is ...
    • Vegetal Oils as Lubricating Materials 

      Calomir, Camelia; Ștefănescu, Ioan; Chiriță, George (Universitatea ”Dunărea de Jos” din Galați, 2008)
      The success of vegetal oils is related to their biodegradability and reduced toxicity but a wide use is limited by their insufficient stability in time. Biodegradable oils have ecological advantages, being comparable or ...
    • Viscosity of Amorphous Molecular Substances 

      Diaconescu, Emanuel; Zegrean, Vlad Flaviu; Onciul Miron, Oana (Universitatea ”Dunărea de Jos” din Galați, 2008)
      Because the great majority of flow units in a liquid behave instantaneously in a solid-like manner, rheological properties of molecular liquids subjected to high pressures may be measured by using corresponding molecular ...
    • Wear Behaviour of the AL7175 Alloy under Different Bulk Stress States 

      Buciumeanu, Mihaela; Miranda, A.S; Silva, F.S (Universitatea ”Dunărea de Jos” din Galați, 2008)
      In what concerns the stresses involved in the process, most wear tests (namely those in the pin on disc and the pin on plate configurations) are usually solely concerned with the stress state in the contact originated by ...