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Publicatii proprii

Începutul suspiciunii. Kant, Hegel & Feuerbach despre religie şi filosofie

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A gear with translational wheel for a variable transmission ratio and applications to steering box

The paper presents the geometric and functional characteristics of a gear with ascending variable ratio, based on the gear with rack and geared segment. This gear can be used for the steering boxes of some low power vehicles (without servo-system). The steering gearbox requires an increase (around 30%) in the transmission ratio from the middle position (rectilinear displacement of the vehicle) to the extreme positions (turning/avoiding obstacles/parking).

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Electrochemical Study on 4-(azulen-1-yl)-2,6-bis(2-furyl)- and 4-(azulen-1-yl)-2,6-bis(2-thienyl)-pyridines

An electrochemical study of 4-(azulen-1-yl)-2,6-bis(2-furyl)- and 4-(azulen-1-yl)-2,6-bis(2-thienyl)-pyridines was performed in order to estimate the influence of electron releasing alkyl substituents on the electrochemical behaviour of these azulenes. The electrochemical parameters obtained by cyclic and differential pulse voltammetry have been correlated with ionization potentials and LUMO energies evaluated through computational methods for the

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Experimental researches and statistical analysis of the corrosion behavior of rolled and heat treated 2xxx Al alloys

The material for experiments was an aluminum alloys series 2xxx obtained by thermo-mechanical processing using different parameters of artificial aging. The slab of Al alloys was rolled at 450-400o C for 7-8 hours. solution treated at 500 +/- 5o C. maintaining time 40 minutes, quenched in water and artificial aging at 100-220o C during respectively 10-240 minutes. After rolling and heat treatment the obtained alloys was corroded in solution of NaCl

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Influence of heat treatment on microstructure and corrosion behavior of 7xxx Al alloys

The influence of heat treatment parameters on mechanical characteristic of hardness and corrosion of aluminum alloys were studied. The 7xxx series aluminium alloy in rolled state was heat treated in the following conditions: solution treatment at 475+/-5oC for 60 minutes, quenched in water 40-60oC and artificial aging at 120, 150, 180, 210oC at different time of aging (60, respectively 300, 540, 720 minutes). The research consisted in intercrystalline

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Fabrication through P/M of ecological aluminum based composite materials. Part 2-Densification and microstructural development during the sintering

In this second part of researches the compacted composites was presintering at 400 degrees C/30 minutes and sintering at different temperatures between 520 and 620 degrees C/ 1 hour maintaining, both thermal treatment made in protective atmosphere for achieved advanced matrix homogeneity and maximum densification. Sintered samples were investigated by parallel techniques, in terms of density/ porosity, dimensional changes during sintering and mechanical

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MICROSTRUCTURE AND TRIBOLOGICAL CHARACTERISTICS OF SINTERED IRON-COPPER BASED COMPOSITE FOR AUTOMOTIVE BRAKE PADS

This paper reports the outcome of morphological and microcompozitional (SEM, EDS, X-Ray Maps, Compo and Morpho images) and tribological (friction and wear) investigations of iron-copper based composite for automotive brake pads. The sintered friction materials were obtained by conventional P/M route, and compared with a commercial brake pad used as reference material. Experimentally chemical compositions of composites established after a number of

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Processing by P/M Route and Characterization of New Ecological Aluminum Matrix Composites (AMC)

The continuous development of technology in automotive manufacturing process has required new solutions adapted to the growing requirements of lightweight, non-pollution for the environment materials with a low cost production. According with these required characteristics of materials, the aims of this paper were to manufacturing Al-Cu/SiCp composites by powder metallurgy (P/M) processing route and characterization of the powders and compacted/sintered

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Morphological and structural aspects using electronic microscopy and image analysis of iron powders obtained by water atomization process

Quality of metal powders depends on manufacturing process and heat treating parameters. Among the physical, mechanical and structural characteristics of powders, the average particle size, size distribution, particle shape and microstructure of powders are defining characteristics to obtain powders with superior performance. The objective of the present paper is to analyze, using electronic microscopy and image analysis , the particle shape and size

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Structural Analysis of PAN Fiber By X-Ray Diffraction,

Polyacrylonitryle (PAN) fibers are used on a large scale in textile industry but, some sorts of PAN fibers are valuable precursors for specific carbon fiber (CF) due to their best fitness to the purpose e.g. for high strength CF or for active CF. The application of PAN as precursors of CF is based on its specific structure and texture. Thus, the properties of PAN base CF strongly depend on PAN structure, texture and fiber morphology. In this respect,

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