Solid Solubility of Carbon in Copper during Mechanical Alloying

Transmission electron microscopy study of copper–carbon nanocomposite

“…A comparison of the finer scaled low mass regions with the specimen edge contour indicates that a localised higher rate of material removal during sample preparation is not likely to be in the origin of the low mass structures. In fact, this type of contrast has not been reported in mechanically alloyed pure Cu after ion 6 Bright field images of strongly diffracting Cu grains situated at edge of a as milled, b and c annealed specimens: dispersion of low mass particles below 10 nm is indicated 4 Electron diffraction patterns of a as milled and b annealed materials obtained from area of 3 mm 2 : contrast was enhanced in magnified insets to turn visible weak Cu 2 O rings; no graphite reflections have been found; expected position of highest intensity graphite peak is indicated 5 Dark field image revealing presence of Cu 2 O nanoparticles and corresponding diffraction pattern where reflections used are circled milling, 32 while it has been observed in C implanted Cu films. 10 The dispersions of low mass regions correspond therefore to carbon agglomerates responsible for the C2C peaks in Raman spectra (Fig.…”

Microstructural Evolution of Cu-10at%C Nanocomposite Powder During High Energy Mechanical Milling

“…The lattice parameter of Cu remains nearly unchanged before milling for 6 h, and increases sharply after milled for 6 h and then reaches its ultimate value. The increase of the lattice parameter of Cu indicates the formation of Cu(C) solid solution [11][12][13]15 . Thus, after milled for 6 h, the concentration of carbon in Cu increases with the increase of milling time, and reaches its saturation milled for 24 h.…”

“…After milling for only 1 h, the diffraction peak of graphite disappeared and the Cu 2 O peak could not be distinguished after 3 h of milling. It was thought that the disappearrance of the graphite diffraction peak indicates the dissolution of carbon in copper matrix 11 , and the Cu 2 O oxide layer might be broken down during milling resulting in disappearance of the Cu 2 O peak.…”

“…In this study, our focus is on the microstructural evolution of Cu-10at%C nanocomposite during HEMM, where the equilibrium solid solubility of carbon in copper is virtually zero 10 . HEMM of Cu-graphite composite powders have been studied by several groups [11][12][13][14][15] . The pioneering studies of Saji et al 11 and Yamane et al 12 on mechanical milling of copper-graphite mixtures with different weight ratio of graphite indicated the solubility of carbon in copper can be as high as 28.5at%, while the study carried out by Marque et al 13 on mechanical milled Cu-10at%C composite showed that the carbon content was overestimated by the former researchers and the existence of carbon nanoparticles was shown.…”

“…HEMM of Cu-graphite composite powders have been studied by several groups [11][12][13][14][15] . The pioneering studies of Saji et al 11 and Yamane et al 12 on mechanical milling of copper-graphite mixtures with different weight ratio of graphite indicated the solubility of carbon in copper can be as high as 28.5at%, while the study carried out by Marque et al 13 on mechanical milled Cu-10at%C composite showed that the carbon content was overestimated by the former researchers and the existence of carbon nanoparticles was shown. Transmission electron microscopy examination confirmed that the microstructure of the mechanically milled Cu-10at%C nanocomposite consisted of nanostructured copper matrix dispersed with carbon nanoparticles 14 .…”