Investigation of microheterogeneities in Ga–Pb melts by acoustic methods

Metastable microheterogeneity in liquid monotectic Bi–Ga alloys

“…Meanwhile, heterogeneity has been found serious in this type of liquid alloy. 22 Filippov and Popel 9 have studied the microheterogeneity in hypermonotectic Ga 60 Pb 40 melt by measuring the ultrasound velocity in various vertical heights of the melt. The difference of ultrasound velocity value between higher and lower part of melt was reduced gradually upon heating not far above phase separation temperature T s , but rapidly in the range 100-150 K above T s .…”

“…[1][2][3][4][5] As a popular result, metastable microheterogeneity was frequently observed in melt during heating and considered to be inherited from ingot. [6][7][8][9][10] This phenomenon is known as a post-melting effect, since the microheterogeneity vanishes under further heating. Microheterogeneity can be well characterised by abrupt change in X-ray diffraction pattern and anomalies in temperature dependences of physical properties of melt (such as ultrasound velocity, viscosity and electrical resistivity) during heating.…”

“…Microheterogeneity can be well characterised by abrupt change in X-ray diffraction pattern and anomalies in temperature dependences of physical properties of melt (such as ultrasound velocity, viscosity and electrical resistivity) during heating. 9,[11][12][13] The characteristic scale of the microheterogeneity (10-100 nm) has been determined by sedimentation experiments 9,14,15 and small angle neutron scattering. 11 Popel et al 10 has summarised and characterised a series of microheterogeneities in liquid eutectic and monotectic system, as well as their influence on properties of solidified alloy.…”

“…Electrical resistivity v. temperature for a Bi 74 9. Ga 25?1 , b Bi 61?5 Ga 38?5 and c Bi 3?5 Ga 96?5 alloys during heating and cooling processes: T s and T l denote respectively beginning and ending of solid-liquid transition in non-isothermal process; T b and T e denote respectively beginning and ending of microheterogeneity-…”

Obtaining Heterogeneous Polymetallic Materials Based on Steel and Copper by the Method of Multiwire Electron-Beam Additive Technology

“…Из-за совместного вклада поверхностной энергии и индуцированной интенсивной конвекции исходный агрегированный богатый железом расплав может постепенно растворяться в объеме жидкости и образовывать гомогенный расплав. После образования гомогенного расплава несмешивающийся сплав Cu-Fe [1,2] в настоящем эксперименте не может достичь достаточно высокой степени переохлаждения, чтобы войти в метастабильный зазор смешиваемости, таким образом, превращение происходит при последующем затвердевании. В результате экспериментальные образцы демонстрируют однородную микроструктуру без крупномасштабной сегрегации состава или пространственного разделения фаз.…”