Obtention of Aluminium-Quasicrystal Composites by Mechanical Alloying

Autor: de Sousa, Fernando Luís Vieira, Romio, Pedro Cordeiro, Passos, Tibério Andrade, de Lima, Severino Jackson Guedes
Zdroj: Materials Science Forum; August 2012, Vol. 727 Issue: 1 p281-286, 6p
Abstrakt: The quasicrystals materials possess a combination of unusual properties, since they present a long range ordered atomic structure, which is not periodic. Because of this, these materials have been object of study of many researchers in the last few years. Currently, the research is focused on determining new techniques able to produce these materials in a large scale, as well as finding new utilities. One of the ways to do so, is to use quasicrystals as coating; another way is the fabrication of composites. In this paper, aluminum composites with the strengthening of quasicrystalline particles from the alloy Al59,2Cu25,5Fe12,3B3 in volumetric fractions of 6% to 20% were developed by high energy ball milling. The powders obtained by mechanical alloying was compacted at 300MPa, sintered and submitted to micro hardness tests. The characterization was made by X-ray diffraction and SEM. In the grinding we used a 2² factorial design with factors time and speed, and the hardness of composite as response. The specimens had an average hardness of 25.75GPa for reinforcement with 6% QC and 34.75GPa for reinforcement of 20% QC.
Databáze: Supplemental Index