TY - JOUR
T1 - Particle size evolution in non-adhered ductile powders during mechanical alloying
AU - Guerrero-Paz, J.
AU - Robles-Hernández, F. C.
AU - Martínez-Sánchez, R.
AU - Hernández-Silva, D.
AU - Jaramillo-Vigueras, D.
PY - 2001
Y1 - 2001
N2 - The interaction among events as deformation, cold-welding and fracture, occurring during the mechanical milling of powders is unclear and controversial. We believe that the understanding of such interaction can be deduced from particle size evolution studies. It is well known that the elemental ductile powders adhere to the milling media. However when some of these powders are combined to form an alloy by milling, the adherence phenomenon is not observed. Systems which include ductile powders, such as, Cu-15at.%Al, Co-68at.%Al and Ni-25at.%Al were processed with not adherence to the milling media, thus allowing to follow up the particle size evolution during the complete milling process. The particle size was measured by the sedimentation-photometry technique. Those results were supported by scanning and transmission electron microscopy. The results showed a high proportion near 95% in number of panicles of submicrometric size at early milling times for the three systems. However its particle size evolution for each system was different. Such findings can be important to understand some mechanisms as the grain size refinement, the alloy formation and the microstructural evolution. In the studied systems, the particle size measurements are presented based on volume or mass, area, line and number of the particles. The particle size results based on volume and line or number of the particles can give an idea of the evolution of the biggest particles and the finest ones respectively during the milling. Also the behavior of the complete particle system can be deduced from the results based in the area of the particles. Results of particle size as well as observations by microscopy helped to suggest the particle size and shape evolution of the studied systems. Such findings were employed to previously propose a grain size refinement mechanism for ductile powder systems non-adherent to the milling media during the mechanical alloying.
AB - The interaction among events as deformation, cold-welding and fracture, occurring during the mechanical milling of powders is unclear and controversial. We believe that the understanding of such interaction can be deduced from particle size evolution studies. It is well known that the elemental ductile powders adhere to the milling media. However when some of these powders are combined to form an alloy by milling, the adherence phenomenon is not observed. Systems which include ductile powders, such as, Cu-15at.%Al, Co-68at.%Al and Ni-25at.%Al were processed with not adherence to the milling media, thus allowing to follow up the particle size evolution during the complete milling process. The particle size was measured by the sedimentation-photometry technique. Those results were supported by scanning and transmission electron microscopy. The results showed a high proportion near 95% in number of panicles of submicrometric size at early milling times for the three systems. However its particle size evolution for each system was different. Such findings can be important to understand some mechanisms as the grain size refinement, the alloy formation and the microstructural evolution. In the studied systems, the particle size measurements are presented based on volume or mass, area, line and number of the particles. The particle size results based on volume and line or number of the particles can give an idea of the evolution of the biggest particles and the finest ones respectively during the milling. Also the behavior of the complete particle system can be deduced from the results based in the area of the particles. Results of particle size as well as observations by microscopy helped to suggest the particle size and shape evolution of the studied systems. Such findings were employed to previously propose a grain size refinement mechanism for ductile powder systems non-adherent to the milling media during the mechanical alloying.
KW - Co-Al
KW - Cu-Al
KW - Mechanical alloying
KW - Ni-Al
KW - Particle size
UR - http://www.scopus.com/inward/record.url?scp=0035006539&partnerID=8YFLogxK
U2 - 10.4028/www.scientific.net/msf.360-362.317
DO - 10.4028/www.scientific.net/msf.360-362.317
M3 - Artículo de la conferencia
AN - SCOPUS:0035006539
SN - 0255-5476
VL - 360-362
SP - 317
EP - 322
JO - Materials Science Forum
JF - Materials Science Forum
T2 - Metastable, Mechanically Alloyed and Nanocrystalline Materials (ISMANAM 2000)
Y2 - 9 July 2000 through 14 July 2000
ER -