http://arthra.ugal.ro/handle/20.500.14043/25569 Sun, 12 Apr 2026 05:41:15 GMT 2026-04-12T05:41:15Z http://arthra.ugal.ro/handle/20.500.14043/25591 Electrochemical Deposition and Sem Surface Morphology of Co and UHMWPE/Co Composite Layers Benea, Lidia; Mardare-Pralea, Marinela; Cojocaru, Paula The work aims at obtaining composite coatings in cobalt matrix with dispersed phase UHMWPE (ultra high molecular weight polyethylene) and at characterizing the surface morphology analyse by SEM, the thickness of the deposited layers and the microhardness of Co and Co/UHMWPE composite coatings. All coatings were obtained on stainless steel plates (304L). The electro-deposition of these metal and composite layers is a process consisting of inclusion of UHMWPE (ultra high molecular weight polyethylene) particles in the cobalt matrix during electroplating process. The dispersed particles were suspended in a sulphate cobalt plating electrolyte within the metal which electro-crystallizes and forms the metal matrix. By means of the potentiostat a number of five current densities were applied during deposition as follow: 23 mA/cm2, 48 mA/cm2, 72mA/cm2, 96mA/cm2 and 120mA/cm2. Keeping particles in suspension was ensured by magnetically stirring at a rotation speed of 300 rotations per minute. After processing the results, it has been noticed that with increasing current density there is an increase in the pure Co layer thickness too as well as in the UHMWPE/Co layers thickness. Adding particles UHMWPE particles in the electrolyte solution, the composite layers thickness is greater as compared with the thickness of pure Co layer obtained under the same electrodeposition conditions. UHMWPE was selected as surface modifier element, due to its high biocompatibility and excellent wear behaviour being used in many biomedical applications. Cobalt is already used in many cobalt alloys as biomedical implants as cobalt – chromium alloys. UHMWPE is also used as bio-polymer in many implants. The metal-matrix composites are materials in which the properties of a metallic host material are modified with addition of a second phase (ceramics, polymers, etc.) by electrodeposition process. THE ANNALS OF “DUNAREA DE JOS” UNIVERSITY OF GALATI. FASCICLE IX. METALLURGY AND MATERIALS SCIENCE N0. 1 – 2009, ISSN 1453 – 083X Thu, 01 Jan 2009 00:00:00 GMT http://arthra.ugal.ro/handle/20.500.14043/25591 2009-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25590 Influence Pressure and Size Particle to Extraction by CO2 Micic, Vladan; Lepojevic, Zika; Jotanovic, Milovan; Tadic, Goran; Mandic, Boris Supercritical fluid extraction (SFE) is an efficient extraction technique for the separation of various organic compounds from herbs, or more generally, from plant materials. These proporties of SFE make the products more advantageous in the field of foods, pharmaceuticals, and cosmetics. The aim of this study was to investigate the effect of pressure and particle size on the extraction yield and the quality of the extracts. THE ANNALS OF “DUNAREA DE JOS” UNIVERSITY OF GALATI. FASCICLE IX. METALLURGY AND MATERIALS SCIENCE N0. 1 – 2008, ISSN 1453 – 083X Tue, 01 Jan 2008 00:00:00 GMT http://arthra.ugal.ro/handle/20.500.14043/25590 2008-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25589 Hydrodynamic Aspects on EAF's Smelt Metallic Mirror Mustaţă, Ruxandra Ioana; Mustaţă, Costică T. Using the Physical and Mathematical knowledge, a new approach to EAF bath’s hydrodynamic aspects is proposed to be developed in this paper. Experimental results and a mathematical equation package have been concluded that the metallic bath mirror has a ondulatory surface during steelmaking process. The shape of slagmetal interface depends on resultant of wave interaction. A higher contact surface between slag and metal correlated with a good velocity of the melted material, lead to a better exploitation of EAF. THE ANNALS OF “DUNAREA DE JOS” UNIVERSITY OF GALATI. FASCICLE IX. METALLURGY AND MATERIALS SCIENCE N0. 1 – 2008, ISSN 1453 – 083X Tue, 01 Jan 2008 00:00:00 GMT http://arthra.ugal.ro/handle/20.500.14043/25589 2008-01-01T00:00:00Z http://arthra.ugal.ro/handle/20.500.14043/25588 The Influence of Cold Rolling on the Mechanical Characteristics for Drawing Steels Potecaşu, Octavian; Potecaşu, Florentina; Alexandru, Petrică; Radu, Tamara The paper presents the changes of the mechanical and technological characteristics of steel for deep drawing, cold rolled and recrystallization heat treated. The research was conducted on samples taken from cold rolled strip, treated and rerolled after the ARCELOR MITTAL technology and, for comparison samples sampled from the steel strip before cold deforming (hot rolled) were used as blank tests. The thermal processing of the cold deformed samples, having different degrees of deformation “ε” (2.2% ; 6.5% ; 15.2%; 32.5% ; 50.0% ; 65.0%) and of the blank tests (ε = 0%) were carried out under industrial conditions in a bell furnace. THE ANNALS OF “DUNAREA DE JOS” UNIVERSITY OF GALATI. FASCICLE IX. METALLURGY AND MATERIALS SCIENCE N0. 1 – 2008, ISSN 1453 – 083X Tue, 01 Jan 2008 00:00:00 GMT http://arthra.ugal.ro/handle/20.500.14043/25588 2008-01-01T00:00:00Z