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Inclusions are the main cause for a series of critical surface and internal defects regarding the quality of cast products. Damage prediction requires knowledge of the number, size distribution, composition and morphology of inclusions that originate upstream and before the casting process. Inclusions in aluminum alloys are usually nonmetallic phases and include oxides, chlorides, carbides, borides, fragment of refractory materials (e.g. silicon carbide) and slag. In aluminum alloys, the most common type of inclusion is aluminum oxide. Industrially, the LiMCA technique is the most applied, which uses an analyzer to in-line determine the impurity degree of the melt, and to detect inclusions in the range of 20-300 µm. [ABSTRACT FROM AUTHOR]

In this paper were highlighted some aspects regarding the manufacturing process of the fiber glass reinforced polymer composites. Polymeric composites reinforced with glass fiber they are used mainly utilized in aircraft industries and is due to low specific weight, increase of corrosion resistance in the fasteners and reduction number of structural components. The paper essentially approaches the steps for the manufacture of a landmark such as ram air inlet. [ABSTRACT FROM AUTHOR]

In this paper a case study was conducted at UAC Europe SRL which aims to analyze the detailed structure of the process components of waste recycling resulting from the extrusion and melting process, prepared to determine the factors underlying success, how the problem was identified, the chosen solutions and the highlighting of the final result, for the recycling of internal and manufacturing waste, the solution adopted and its advantages. [ABSTRACT FROM AUTHOR]

In this paper the principle of the method of covering surfaces with granular type activated material with epoxy primer 310 in electrostatic field, implementation of coating technology in electrostatic field, research methodology and tests has been investigated. Four metallic samples were tested whose surfaces were previously pre-treated (degreasing and pickling) and covered at 10, 15, 20 and 25 microns thicknesses. As for the appearance of the samples, they were visually inspected and then examined under the optical microscope. The samples did not show porosity due to the heat treatment. Also, the characteristics of the deposited layer show a matte appearance, without scratches or blisters and without sediment, the adhesion is uniform and the deposited layers are compact. [ABSTRACT FROM AUTHOR]

In this paper, the samples were heat treated by two-stage artificial aging to investigate the effect on the mechanical properties of the 7150-T77 aluminum alloy, and finally subjected eventually to the ESCO corrosion test according to ASTM G34-01 standard. The results have shown that the mechanical properties and corrosion resistance induced by cracking at alloy 7150 can be improved by two-stage customized heat treatment for a specific application in the aeronautical industry. [ABSTRACT FROM AUTHOR]

Idea in this work has been performed the susceptibility to intergranular corrosion of high strength aluminum alloy 2024 in aggressive corrosion environments. Intergranular corrosion is limited to the immediate area of the grain boundary and is not apparent by simple visualization and the resistance to intergranular corrosion of aluminum alloys in the Al-Cu-Mg system is related to the heating conditions applied during the solution treatment. This is can be an important source of limiting the life of the aircraft body where alloys from the 2xxx series are used, which is why they are systematically subjected to intergranular corrosion tests in dedicated laboratories. [ABSTRACT FROM AUTHOR]

The powder compact melting technique for aluminium foam production as practised today accepts a certain mismatch between foaming agent decomposition and matrix alloy melting temperatures.This mismatch is believed to influence the pore structure in an unfavourable way. Adjustment of TiH2 decomposition as well as liquidus and solidus temperatures of matrix alloys can be used to counteract it. Effects of TiH2 thermal are investigated using thermal analysis. TiH2 variants gained via annealing treatments were used to produce aluminium foam precursor materials. [ABSTRACT FROM AUTHOR]

Pastes of granulated blast furnace slag and zeolitic tuff at different mass ratios were activated with alkali solution (sodium silicate) at lower alkalinity with modulus Ms= %SiO2 /%Na2O = 2 . The heavy metals contained in slag are immobilized into geopolymer matrix of composite material, so obtained and thus significantly reduces the risk of environment contamination. Granulated lead furnace slag, zeolitic tuff, sodium hydroxide and sodium silicate were used as starting materials. Binder of 50% slag developed the highest among all slag based geopolymeric pastes whose compressive strength are 42 MPa. As a result, the cement containing 50% slag that is synthesized at curing (600 C for 12 h), exhibited higher mechanical strength and SEM observation shows that it is possible to have localized of (C-S-H) geopolymeric gel. Pastes of granulated blast furnace slag (GBFS) and zeolitic tuff (BZ) in mixture developed stable microstructures with high compressive strengths, and the toxic metals (Pb, Zn, Cd) from slag were locked into the geopolymeric matrix. [ABSTRACT FROM AUTHOR]

In this study, was conducted a current state of the sources of greenhouse gases, emission by the Industrial Sector and the Metallurgical Processes Industry and a process-based LCA has been performed for the pyro-lead metallurgical process based on non-ferrous metallurgical plant in Maramures County (Romania). The purpose of this study is to highlight areas of the lead and copper metallurgical process, which contributes most significantly to potential environmental impacts, there by identify the areas of potential improvement, and eventually provide a scientific basis for the improvement on resource and energy use as well as in emission control and to ultimately implement its clean production for lead metallurgical processes. Massive reductions in greenhouse gas emissions should stabilize climate risk and avoid catastrophe. Life cycle assessment (LCA) is a useful and effective tool to address environmental performance and potential impact a product throughout its life cycle. In Maramures county was a reduction in emissions of greenhouse gases as a result of reduced industrial activity in the two-ferrous metallurgical works: Romplumb SA and Cuprom SA Baia Mare. [ABSTRACT FROM AUTHOR]

In order to improve the technology for copper electrolysis, I suggest several changes to the copper electrolysis cell such as: replacing the material from which the electrolysis cell is made with plastic material. This is a good insulator reducing the lost quantity of current in the ground, preventing copper sedimentation on the surface of the cell and maintaining a constant temperature inside the cell. Another change would be: the anodes from the electrolysis cell must be equipped with two separators to allow equal space between the electrodes and to prevent contact between these which could otherwise lead to short circuits and ultimately to the slowing down or termination of the electrolysis process. In order to improve the electric contact, the feeder needs an electrolytic conductor bath and then a water wash at the changing of the anodes. So as to prevent the waste of thermal energy and the electrolyte's evaporation, I suggest covering each electrolysis cell with a protection lid. [ABSTRACT FROM AUTHOR]

The aim of this paper was to elaborate a manufacturing technology of a cuprous oxide pellets from concentrates, applicable at industrial level. The experimental researches started on the premise to establish a formula for the preparation of raw material as easy to process further to melting in the blast furnace, respectively to minimize the possible using of additional auxiliary materials. The experiments performed aimed to establish the following parameters:the composition of the charge, and the formula, the type of binder,the post-pelletising operations [ABSTRACT FROM AUTHOR]

This work is focussed on copper refining by the injection of soda ash powder. Experiments were carried out using 15 kg copper bath at two temperatures, 1200 and 1250°C. The carrying gas used for the injection trials was air with flow rates of 3,5 and 10 l/min. The results show that the copper refining process is more efficient at temperatures for the Na2CO3 injection process where as high temperatures produce better antimony removal for the injection of Na2CO3 powder. Na2CO3 injection with the air flow rate (10 l/min) produced higher removal rates. The kinetic model was adapted to the copper refining process to predict the rate antimony removal in terms of temperature and flow rate [ABSTRACT FROM AUTHOR]

This research aimed at analysing the acidic corrosion behavior of aluminum alloy 2024-T3 commonly used in the aerospace. We study the variation of corrosion rate with immersion time at different values of H2SO4 concentration and corrosion rate variation depending on the concentration of the solution setting the group of corrosion of the alloy. Aluminum forms initially a few-nm-thick layer of aluminum oxide, γ-Al, which after prolonged exposure in humidified air is covered by aluminum oxyhydroxide, γ-AlOOH, and subsequently by various hydrated aluminum oxides and aluminum hydroxides. The exposed metal surfaces involved aspects of the corrosion process in 0.1M H2SO4, 0.01M H2SO4 and 0.001M H2SO4 solutions, to determine the type of corrosion and propagation mechanism in acidic environments. [ABSTRACT FROM AUTHOR]

In the view of limiting the global temperature increasing, the green house emissions respectively, Romania has to act immediately, especially in the energetic efficiency field and of energetic renewable sources. The actions regarding the energetic efficiency and the energetic renewable sources will contribute both at diminishing the negative pollutions impact on the environment and at limiting of Romania dependency for the energy import. The reinforcement of developing conditions for the biofuel sector in Europe has been materialized by drawing up the Directive 2003/30/CE, having as target the promoting of biofuels usage in transport. That directive provides the introduction on the market by each EU member state of a minimum production of biofuels and other renewable fuels, calculated on the base of the energy contained of all types of petrol and diesel used in transport. This directive has been transposed in Romanian legislation by the Governmental Decision no. 1844/2005, concerning the promoting of biofuels and other renewable fuels usage in transport, completed and rectified by the Governmental Decision no. 456/2007 which stipulates a phasing for introduction on the Romanian market of the blended biofuels and conventional fuels. [ABSTRACT FROM AUTHOR]