By means of Gibbs-Bogoliubov (GB) thermodynamic variational calculation,the thermodynamic properties of the supercooled liquid metals,such as the 3rd family elements Al,Ga and Tl and transition metal Ti were calculate...By means of Gibbs-Bogoliubov (GB) thermodynamic variational calculation,the thermodynamic properties of the supercooled liquid metals,such as the 3rd family elements Al,Ga and Tl and transition metal Ti were calculated using the hard-sphere (HS) system as reference.The values of mean atomic volume,Helmholtz free energy,internal energy and entropy as well as specific heat at constant volume,isothermal bulk modulus,thermal expan- sion coefficient and specfic heat under constant pressure were evaluated.The glass transition temperature,T_g,is easily obtained from the C_p-T plot.The glass forming ability for metal can be predicted from T_g/T_m,which is in agreement with the experimental results.展开更多
Local arrangement of atoms in supercooled liquid Ni_(80)P_(20) alloy has been investigated by using NPT-MD simulation techniques based on the effective pair Potentials derived for Ni-P system. Bond-orientational order...Local arrangement of atoms in supercooled liquid Ni_(80)P_(20) alloy has been investigated by using NPT-MD simulation techniques based on the effective pair Potentials derived for Ni-P system. Bond-orientational order, the long-range correlation function and symmetrical parameters by pair-analysis approach have been calculated for supercooled liquid Ni_(80)P_(20) alloy. Results show. that in case of Ni_(80) .P_(20) alloy, the local structure is all random-like whether the centre of cluster is located at atoms Ni or P. It indicates that the icosahedral symmetry is not the unique model to describe the microstructure in supercooled liquid metals.展开更多
Metallic glasses（MGs）are considered as the ideal materials for miniature fabrication because of their excellent micro thermoplastic forming ability in the supercooled liquid region.The understanding and controlling ...Metallic glasses（MGs）are considered as the ideal materials for miniature fabrication because of their excellent micro thermoplastic forming ability in the supercooled liquid region.The understanding and controlling of micro filling process are fundamental for miniature fabrication and their applications,yet presently remain unresolved issues.A universal kinetic equation was proposed to describe the filling kinetics of viscous metallic glass supercooled liquid in micro molds with general cross sectional shapes by using a Pdbased MG as the modeling material and a series of potential applications based on the micro thermoplastic forming of the MG were developed.展开更多
文摘By means of Gibbs-Bogoliubov (GB) thermodynamic variational calculation,the thermodynamic properties of the supercooled liquid metals,such as the 3rd family elements Al,Ga and Tl and transition metal Ti were calculated using the hard-sphere (HS) system as reference.The values of mean atomic volume,Helmholtz free energy,internal energy and entropy as well as specific heat at constant volume,isothermal bulk modulus,thermal expan- sion coefficient and specfic heat under constant pressure were evaluated.The glass transition temperature,T_g,is easily obtained from the C_p-T plot.The glass forming ability for metal can be predicted from T_g/T_m,which is in agreement with the experimental results.
文摘Local arrangement of atoms in supercooled liquid Ni_(80)P_(20) alloy has been investigated by using NPT-MD simulation techniques based on the effective pair Potentials derived for Ni-P system. Bond-orientational order, the long-range correlation function and symmetrical parameters by pair-analysis approach have been calculated for supercooled liquid Ni_(80)P_(20) alloy. Results show. that in case of Ni_(80) .P_(20) alloy, the local structure is all random-like whether the centre of cluster is located at atoms Ni or P. It indicates that the icosahedral symmetry is not the unique model to describe the microstructure in supercooled liquid metals.
基金The financial support of the Science and Technology Innovation Commission Shenzhen(Grant Nos.JCYJ20150625102923775 and JCYJ20160520164903055)
文摘Metallic glasses（MGs）are considered as the ideal materials for miniature fabrication because of their excellent micro thermoplastic forming ability in the supercooled liquid region.The understanding and controlling of micro filling process are fundamental for miniature fabrication and their applications,yet presently remain unresolved issues.A universal kinetic equation was proposed to describe the filling kinetics of viscous metallic glass supercooled liquid in micro molds with general cross sectional shapes by using a Pdbased MG as the modeling material and a series of potential applications based on the micro thermoplastic forming of the MG were developed.
