TY - JOUR
T1 - Synthesis and microstructural characterization of Al-Ni3Al composites fabricated by press-sintering and shock-compaction
AU - Hernández, Pamela
AU - Dorantes, Héctor
AU - Hernández, Felipe
AU - Esquivel, Ramón
AU - Rivas, Diego
AU - López, Víctor
PY - 2014/1
Y1 - 2014/1
N2 - Aluminum matrix composites reinforced with nanocrystalline Ni3Al intermetallic particles, were synthesized using powder metallurgy techniques. Nanocrystalline Ni3Al was obtained by mechanical alloying of Ni75-Al25 stoichiometric mixture from elemental powders after 900 ks of milling with a 5 nm grain size average. Mixture powders of aluminum with 0.007, 0.02 and 0.04 volume fractions of Ni3Al intermetallic particles were compacted using two different compaction methods, the cold isostatic press and sintered at 873 K and the shock-compaction technique. Microstructure of shock-compacted composites showed fine particles of a few microns and also coarse particles less than 100 μm homogeneously distributed on the matrix, also the presence of micro-cracks and low porosity. However the nanoscale features of intermetallic was retained. On the other hand, the press and sintered composites showed good densification. The densities of the composites were about 90% and 94% of the theoretical density for the shock-compacted and press-sintered process, respectively. Finally, the results of hardness measurements showed that the nanocrystalline Ni3Al reinforcement improves the hardness of Al matrix for all conditions. The highest hardness was obtained for the Al-4 vol.%Ni3Al shock-compacted composite.
AB - Aluminum matrix composites reinforced with nanocrystalline Ni3Al intermetallic particles, were synthesized using powder metallurgy techniques. Nanocrystalline Ni3Al was obtained by mechanical alloying of Ni75-Al25 stoichiometric mixture from elemental powders after 900 ks of milling with a 5 nm grain size average. Mixture powders of aluminum with 0.007, 0.02 and 0.04 volume fractions of Ni3Al intermetallic particles were compacted using two different compaction methods, the cold isostatic press and sintered at 873 K and the shock-compaction technique. Microstructure of shock-compacted composites showed fine particles of a few microns and also coarse particles less than 100 μm homogeneously distributed on the matrix, also the presence of micro-cracks and low porosity. However the nanoscale features of intermetallic was retained. On the other hand, the press and sintered composites showed good densification. The densities of the composites were about 90% and 94% of the theoretical density for the shock-compacted and press-sintered process, respectively. Finally, the results of hardness measurements showed that the nanocrystalline Ni3Al reinforcement improves the hardness of Al matrix for all conditions. The highest hardness was obtained for the Al-4 vol.%Ni3Al shock-compacted composite.
KW - Aluminum matrix composite
KW - Intermetallics
KW - Mechanical alloying
KW - Powder metallurgy
KW - Shock-compaction
UR - http://www.scopus.com/inward/record.url?scp=84896395246&partnerID=8YFLogxK
U2 - 10.1016/j.apt.2013.04.011
DO - 10.1016/j.apt.2013.04.011
M3 - Artículo
SN - 0921-8831
VL - 25
SP - 255
EP - 260
JO - Advanced Powder Technology
JF - Advanced Powder Technology
IS - 1
ER -