Abstract: In this study, Friction Stir Processing (FSP) a recent grain refinement technique was employed to disperse micron-sized (2 *m) SiCp particles into aluminum alloy AA6063. The feasibility to fabricate bulk composites through FSP was analyzed and experiments were conducted at different traverse speeds and wider volumes of the specimens. Micro structural observation were carried out by employing optical microscopy test of the cross sections in both parallel and perpendicular to the tool traverse direction. Mechanical property including micro hardness was evaluated in detail at various regions on the specimen. The composites had an excellent bonding with aluminum alloy substrate and a significant increase of 30% in the micro hardness value of metal matrix composite (MMC) as to that of the base metal has observed. The observations clearly indicate that SiC particles were uniformly distributed within the aluminum matrix.
Abstract: Within this work High Temperature Single Impact
Studies were performed to evaluate deformation mechanisms at
different energy and momentum levels. To show the influence of
different microstructures and hardness levels and their response to
single impacts four different materials were tested at various
temperatures up to 700°C. One carbide reinforced NiCrBSi based
Metal Matrix Composite and three different steels were tested. The
aim of this work is to determine critical energies for fracture
appearance and the materials response at different energy and
momenta levels. Critical impact loadings were examined at elevated
temperatures to limit operating conditions in impact dominated
regimes at elevated temperatures. The investigations on the
mechanisms were performed using different means of microscopy at
the surface and in metallographic cross sections. Results indicate
temperature dependence of the occurrence of cracks in hardphase
rich materials, such as Metal Matrix Composites High Speed Steels
and the influence of different impact momenta at constant energies
on the deformation of different steels.