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The aim of the present paper were to determine compressibility behavior of post-compacts depending on compaction pressure and the silicon carbide content in the Al-Cu matrix powder mixtures. Determination of Al- 4wt.% Cu with 5-20 wt.% SiC powder mixtures' compressibility was performed in a double action hardened steel die at pressures between 50-450 MPa. For understanding of compaction behavior of Aluminum based composites reinforced with silicon
Read moreThe hardening state through mechanical deformation emphasized in internal structure of materials, in according with the processes of elastic-plastic deformation enables us for particular behavior laws, introducing of a dual frame needed by the treatment of quasi-static equilibrium equations. Introduction of a Hilbert space for admissible deformations of a mechanical system, following a hardening process of a cold deformed composite, a process governed
Read moreThe present work is intended as a synthesis of fundamentals regarding the achievements of successive generation of refractory concretes. In order to reach this goal both the results of our own researches and information from literature have been used. A unitary concept is developed on binding system belonging to this category, on mechanisms and processes that take place during hardening and on the behavior of these systems during service.
Read moreIn this paper, the relative humidity is monitored with weather station at the UPB ISB faculty during September-December 2009. In this paper we monitored the relative humidity, we plotted the values obtained and then we made a statistical analyzing of obtained date. After analyzing the data we notices that: the lowest humidity in September was recorded on September 04, 05 September 2009 at 17:00 worth 28 % and the highest value on September 6, 7 2009
Read moreIn the present paper, relative humidity variation was analyzed every week from autumn months of 2009, and analysis was done for the 1st day of September and the last day of December 2009. Relative humidity variation analysis was made based on the records of the atmospheric parameters of the weather station equipment from Biotechnical Engineering Faculty of the University "Politehnica" of Bucharest (UPB). Based on records maintained by AWS weather
Read moreThe 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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