Characterization of Sintered Hardmetals Coated with TiC

This paper presents the realization of TiC thin films by CVD method. The thin layers of TiC thicknesses were 8 and 10 μm, their thickness increasing with time, keeping the temperature. Diffractometer analysis certifies that this thin layer of TiC is homogeneous and unscratched. Microhardness of thin layers of TiC is HV0,05 = 30000 MPa compared to WC (carbide substrate of the component) that has a microhardness HV0,05 = 17000MPa

Study And Researche Regarding Binaring Sistem With Tiobis - β – Naftol

This paper presents the results for contribution of determining the manganese from waters and steel. Manganese, due to its properties, cannot be found but in acid waters and usually associated with iron. In small amounts, the manganese is a necessary nutrient above all as activator of certain enzymes. In large amounts, though, coming from contaminated waters , the manganese is noxious and may cause brain damage l. It is considered that drinking water should not contain more than 0,1 ppm manganese. From the studies carried out , the tiobis-β-naftolul dissolved in etilic alcohol or isobutilic alcohol may be used to determine the Mn (II) ion , under certain conditions as described in the paper. To determine manganese (II) in water, a photometric extraction method has been developed. The method is new, useful and accurate and enables determining Mn in surface, underground and fishery waters

Composite Coating in Copper Matrix with Molybdenum in Dispersion Phase Obtained by Electrochemical Methods

The paper describes reviews referring to determination of working parameters of the development processes of composites in copper matrix, obtained by electrochemical deposition methods. The molybdenum particles having particle sizes of 3 μm, respective 7 μm have been used as a complementary phase. The optimal conditions for codeposition were determined, the structure and chemical composition of the obtained coatings were presented and the coating characteristics were tested

Structure-Property Correlation of Composite Materials Based on Cu-Mo Obtained by PVD Method

The paper describes reviews referring to determination of working parameters of the development processes of composites in copper matrix, by vapour-phase deposition method. The molybdenum was used as complementary phase. Structural characterization of coatings developed by optical microscopy and electronic scanning and effects of surface structure on their characteristics were presented. The specificity of the technology for obtaining Cu-Mo composites is a condition to formation a special laminated structure. The mechanical characteristics of the condensate depending on the amount of molibden. An important role in forming the structure and characteristics is played by the defects which were formed in the condensate during the transfer in the liquid phase as drops. Electrochemical tests have shown that the corrosion resistance of the composites obtained by PVD method is higher than pure copper

Corrosion Resistance in Neutral Saline Fog of the Composites Cu-Mo Obtained by PVD Method

The basic materials used for electrical contacts, which may be available economically, are the Cu-Mo based composites obtained by the method of electron flow at high temperatures under vacuum. Cu-Mo (12% max. Mo) composite materials are produced by simultaneous evaporation from separate Cu and Mo crucibles with subsequent condensation of the vapor flow on an OL-37 steel layer of 15 to 20 mm thickness and 800 mm diameter. The surface of the disk-support on which condensation of the vapor flow takes place was machined until a roughness of Ra =0.63 was obtained. Analysis of chemical composition and structure of composites based on copper and molybdenum content allowed determination of the variation of these elements from layer to layer (of up to 20-25% to 4-5 mas.) and the distribution gradient of these elements in the layers. The Cu-Mo composites produced by PVD method were introduced in the room and tested in neutral saline fog exposure time of 100h. Cu-Mo composites, obtained by PVD method, have a fairly good corrosion resistance, at Mo concentrations ranging from 8% to 12 % of the surface do not present oxides and the concentrations of Mo between 1,2 to 6% area are covered with oxide