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Abstract: The atomic structures of liquid Cu–Ag alloys (Cu80Ag20, Cu60Ag40, Cu40Ag60 and Cu20Ag80) have been investigated in the solidification process by means of X-ray diffraction. The results show that the liquid structures of Cu–Ag alloys, which are micro-homogeneous and similar with their solid state, display quite stable changes on a large-scale range indicated by the correlation radius r c, although the short-range order structures change obviously around their liquidus (liquid–solid transformation). This is different from the results of the In30Sn70 alloy we previously reported, which shows an abrupt structure changes around its liquidus. In addition, the Gaussian peaks decomposition of the radial distribution functions (RDF(r)) was also performed to shed light on the element distribution and structure evolution in the whole solidification process especially around the liquidus. [Copyright &y& Elsevier]

Abstract: The structural parameters of Au75Si25 alloy, pure Au, Al88Si12, Cu87Sn13, In98Al2 and Al93Ni7 alloys have been measured by X-ray diffractometer. It is found that there are subpeaks in the pair correlation functions in liquid Au75Si25 alloy. The addition of Si in liquid Au results in a decrease in both the correlation radius and the coordination number of the nearest atomic neighbors. The Au75Si25 alloy nearest atomic distance has a more stable dependence on temperature compared to In98Al2, Al93Ni7 and Cu87Sn13 alloys. The atomic density change of liquid Au75Si25 alloy is less dependent on temperature than the liquid Au and Al88Si12 alloy. The liquid metallic good glass former Au75Si25 alloy possesses a more stable liquid structure than that of poor glass formers, indicating the essential of the fragility of the superheated melts. [Copyright &y& Elsevier]

Abstract: X-ray diffraction experiment has been carried out on In30Sn70 binary alloy from normal liquid 400 °C to the temperature near the solidus 125 °C ( and is about 172 and 120 °C, respectively). The results show that the correlation radius , the correlation length D and the atom numbers have an abrupt increase near the liquidus with the temperature decreasing. Which indicates an abrupt structure change in the nucleus forming process. This result is different from our recent study on Cu80Ag20 alloy, which show a stable structure change around the liquidus. In addition, the coordination number comparing with the viscosity measurement indicates a temperature and component induced discontinuous structural change region between about 165 and 145 °C. [Copyright &y& Elsevier]

Abstract: Local structure of Cu–20at.%Sb melts has been studied by X‐ray diffraction and ab initio molecular dynamics simulation. Pre‐peaks in relation with medium‐range order are observed in structure factor. Negative Warren–Cowley parameters reflect the existence of chemical order. With an obvious pre‐peak, broadening intensities of Cu3Sb are in good agreement with experimental results, indicating structure similarity of Cu3Sb to ordered clusters in the melts. These imply that origin of pre‐peaks is in relation with Cu3Sb‐like clusters. Abnormally large activation energy of viscous flow and negative temperature coefficient of resistivity are well interpreted as the existence of medium‐range order clusters. [Copyright &y& Elsevier]

Abstract: The liquid structures in the solidification process of the Cu100− x Sn x (x =10, 20, 30, 40) alloys were investigated by X-ray diffraction method. The results show that the Cu3Sn and quasi Cu3Sn structures exist in the Cu–Sn liquids. Which arouses an obvious structure change indicated by the correlation radius r c at about 900°C. In addition, the structure change induced by the liquid–solid transition at about 30–40°C below the liquidus is also observed. [Copyright &y& Elsevier]

Abstract: Using viscometer, densitometer, magnetic susceptibility device, DSC and X-ray diffractometer for high temperature (XRD), the Pb melt has been investigated between 800–1200 K. Anomalous changes in the physical properties were found near the same temperature. X-ray diffraction shows that the size of clusters in the low temperature zone is much larger than that in the high temperature zone. It is presumed that some solid-like structure occurred at the anomalous point of the physical properties during the cooling process. [Copyright &y& Elsevier]

Abstract: The atomic structure in the solidification process (from 1200 to 780 °C, and is about 950 and 780 °C respectively) of Cu80Ag20 binary alloy has been investigated by X-ray diffraction technique. The correlation radius and the atom numbers of the cluster show a little increasing with the temperature decreasing bellow 1100 °C. The correlation length D shows almost a linear change with the temperature. All these results indicate a quite stable structure change in the solidification process of Cu80Ag20 alloy. This is quite different from our former study on In30Sn70 alloy, which shows an abrupt increasing both for , and D around its liquidus. As liquid clusters play a crucial role in the forming of crystalline nucleus and they may serve as the embryo of the nucleus, which means two different nucleus forming mechanism. We consider the Cu80Ag20 like as stabilization mode and the In30Sn70 like as saltation mode. In addition, the moving of atoms in the solidification process is also discussed by the Gaussian peaks decomposing of the . [Copyright &y& Elsevier]

Abstract: The structure of In–1% Cu, In–1% Al and In–1% Sn (mass fraction) alloy melt were investigated in the temperature range 280 to 750°C by using a high-temperature X-ray diffractometer, and were compared with that of pure In melt. The experimental results show that, with the addition of 1% Cu, 1% Al or 1% Sn, thermal contraction phenomenon of atom clusters can be found in melts as temperature increases like in pure In melt. But the degree and the characteristic of thermal contraction are different from those of pure In melt. The contraction increases with the addition of 1% Cu or 1% Al and decreases with the addition of 1% Sn. With the addition of 1% Cu, the sudden change and noticeable contraction are measured in the range of 280–390°C. The temperature range is lower than that of pure In melt. With the addition of 1% Al or 1% Sn, the contraction is not consistent in whole measurement temperature range. The anomalous change occurs at about 390 and 550°C, respectively. [Copyright &y& Elsevier]

Abstract: The structure of Cuand Cualloy melts were studied by using a high-temperature X-ray diffractometer. The radial distribution functions (RDF) were obtained, which reflect the structure information of melts in real space. Gaussian decomposition of the RDFs shows the changing behavior of Culusters in the melts. The interatomic distance and the atom number of the clusters decrease with increasing temperature. The structure evolution and the so-called “thermal contraction” of clusters in the melts are discussed. [Copyright &y& Elsevier]

Abstract: Atomic structure of Cu37Sb63 and Cu20Sb80 melts has been studied by high temperature X-ray diffraction and viscosity measurement. Split main peaks indicate Cu–Sb heterogeneous and Sb-homogeneous clusters dominate in these two melts, respectively. This results in the smaller first-neighbor radius and higher viscosity in Cu37Sb63 melts. In pair distribution functions of Cu20Sb80 melts, the hump around 0.44nm becomes obvious below 973K, which reveals the reinforcement of Sb clusters with Peierls distortion. This is consistent with the increase in viscous-flow activation energy in Cu20Sb80 melts around 973K. Structure parameters change is also discussed in terms of clusters evolution during cooling. [Copyright &y& Elsevier]