A novel technique was developed for the preparation of Cu-15 wt pct Cr composite with high strength and conductivity. The composite powders with refined microstructure and curly lamellae strengthening phase was first ...A novel technique was developed for the preparation of Cu-15 wt pct Cr composite with high strength and conductivity. The composite powders with refined microstructure and curly lamellae strengthening phase was first prepared by mechanical milling in favorite milling time and then were hot hydrostatic extruded after pre-densification with sintering or hot pressing. It was shown that the extrusion densified the composite powders well and at the same time the chaos curled strengthening phase was aligned into lines and further deformed as strengthening ribbons. The deformation processed Cu-15 wt pct Cr composite prepared by this technique is of superior conductivity, strength and thermal stability.展开更多
Copper-based composites strengthened by ceria nanoparticles were processed by conventional powder metallurgy: mixing (30 min and 46 rpm), compaction (cold, uniaxial, 1080 MPa for 10 s) and sintering (800°C for 6 ...Copper-based composites strengthened by ceria nanoparticles were processed by conventional powder metallurgy: mixing (30 min and 46 rpm), compaction (cold, uniaxial, 1080 MPa for 10 s) and sintering (800°C for 6 h in vacuum atmosphere of 10−5 torr). It was studied the microstructure (optical microscopy, scanning electron microscopy), X-ray diffraction with Rietveld refinement and some properties (electrical conductivity, Vickers hardness and fracture analysis) of the compositions 92 wt% Cu - 8 wt% CeO2 and 80 wt% Cu - 20 wt% CeO2. The results showed uniform phase distribution, low porosity and ceria disperse inside copper grain. In despite of properties, the composites had electrical conductivity of 38% IACS and 15% IACS and hardness of 69 and 88 HV5, respectively. The results of 92 wt% Cu - 8 wt% CeO2 composites were promising, and they are in according with actual literature.展开更多
文摘A novel technique was developed for the preparation of Cu-15 wt pct Cr composite with high strength and conductivity. The composite powders with refined microstructure and curly lamellae strengthening phase was first prepared by mechanical milling in favorite milling time and then were hot hydrostatic extruded after pre-densification with sintering or hot pressing. It was shown that the extrusion densified the composite powders well and at the same time the chaos curled strengthening phase was aligned into lines and further deformed as strengthening ribbons. The deformation processed Cu-15 wt pct Cr composite prepared by this technique is of superior conductivity, strength and thermal stability.
文摘Copper-based composites strengthened by ceria nanoparticles were processed by conventional powder metallurgy: mixing (30 min and 46 rpm), compaction (cold, uniaxial, 1080 MPa for 10 s) and sintering (800°C for 6 h in vacuum atmosphere of 10−5 torr). It was studied the microstructure (optical microscopy, scanning electron microscopy), X-ray diffraction with Rietveld refinement and some properties (electrical conductivity, Vickers hardness and fracture analysis) of the compositions 92 wt% Cu - 8 wt% CeO2 and 80 wt% Cu - 20 wt% CeO2. The results showed uniform phase distribution, low porosity and ceria disperse inside copper grain. In despite of properties, the composites had electrical conductivity of 38% IACS and 15% IACS and hardness of 69 and 88 HV5, respectively. The results of 92 wt% Cu - 8 wt% CeO2 composites were promising, and they are in according with actual literature.
