An investigation on morphology and structure of Cu-Cr-Al2O3 powders prepared by mechanical milling

Abstract

Abastract：In this study, the effect of the milling time on microstructure of Cu-0.5 wt.% Cr-1 wt.% Al 2 O 3 was investigated. The lattice parameter was evaluated by the X-ray diffraction technique. The microstructure was characterized by scanning electron microscopy. Also, size and distribution of Cr and Al 2 O 3 were investigated by using X-rays energy dispersive (EDX) mapping. The result shows that the lattice parameter of the Cu phase increases with increasing milling time. The changing trend of Cu particle sizes as the alloying time increases, the particle sizes first increase and then decrease. When milling 1.5h, the powders coarsen than as-received Cu powder. Then the particle sizes of the samples decreased when the milling time increased to 3h and above. In addition, the size and distribution of Cr and Al 2 O 3 decreased and dispersed much fine with increasing milling time.

Archives of Metallurgy and Materials

“…however, a portion of the ceramic particles retained their shapes and were not alloyed. This indicated that sintering of the green compact, produced after pressing the mixed powder, may create voids owing to the ceramic particles that were deformed or retained their shape, resulting in the formation of pores in the composite [10][11][12][13]. The uniform distribution of additives in the Cu base, which is the main conductivity channel, degrades the electrical properties; however, it increases the hardness, thereby improving the overall physical properties.…”