Papers by Author: M.L. Delgado

Abstract: Consolidation of aluminium alloys by sintering present a main problem: the oxide layer that cover aluminium particles. Some alternatives are studied in this work as solution to the oxide layer problem during the sintering of series 2xxx aluminium alloys. One of these solutions is related to the addition of tin traces, and the other is the addition of a second alloy. Moreover, aluminium metal matrix composites are characterized by excellent properties as combination of properties which comes from the matrix and from the reinforcement. In the first part of this work is analyzed the influence of trace additions, and the last part of this study is focused to the analysis of one aluminium matrix composite as the influence of several quantities of reinforcement.

Abstract: The increasing demand of PM parts for automobile and aerospace applications has caused a strong development of the aluminium based metal matrix composites (MMCs).Aluminium alloys are one of most widely used materials as matrix in MMCs, both in research and development as well as in industrial applications. The main reason is the combination of good specific properties, the first requirement in most applications, and the competitive price compared to other low density alloys such as Mg or Ti alloys. In the present work, the influence of the ceramic reinforcement addition to a 2xxx series aluminium alloy is studied. Several percentages of TiCN have been added to the Al-Cu alloy using PM techniques, in order to analyze its influence on the liquid phase sintering process and also on the final properties of the material. The materials have been uniaxially compacted using two different pressures to determine the optimal pressing condition. They have been subsequently sinterized in a N2-H2 atmosphere. Analysing the results obtained, it can be concluded that the addition of TiCN allows a better distribution of the liquid phase up to the 10 %wt, where the optimal results are observed: For higher quantities of reinforcement, elemental copper is observed in the microstructure with the consequent decrease in densification.