摘要
The thermal stability of Ti@Al core/shell nanoparticles with different sizes and components during continuous heating and cooling processes is examined by a molecular dynamics simulation with embedded atom method. The thermodynamic properties and structure evolution during continuous heating and cooling processes are investigated through the characterization of the potential energy, specific heat distribution, and radial distribution function(RDF). Our study shows that, for fixed Ti core size, the melting temperature decreases with Al shell thickness, while the crystallizing temperature and glass formation temperature increase with Al shell thickness. Diverse melting mechanisms have been discovered for different Ti core sized with fixed Al shell thickness nanoparticles. The melting temperature increases with the Ti core radius. The trend agrees well with the theoretical phase diagram of bimetallic nanoparticles. In addition, the glass phase formation of Al–Ti nanoparticles for the fast cooling rate of 12 K/ps, and the crystal phase formation for the low cooling rate of 0.15 K/ps. The icosahedron structure is formed in the frozen 4366 Al–Ti atoms for the low cooling rate.
The thermal stability of Ti@Al core/shell nanoparticles with different sizes and components during continuous heating and cooling processes is examined by a molecular dynamics simulation with embedded atom method. The thermodynamic properties and structure evolution during continuous heating and cooling processes are investigated through the characterization of the potential energy, specific heat distribution, and radial distribution function(RDF). Our study shows that, for fixed Ti core size, the melting temperature decreases with Al shell thickness, while the crystallizing temperature and glass formation temperature increase with Al shell thickness. Diverse melting mechanisms have been discovered for different Ti core sized with fixed Al shell thickness nanoparticles. The melting temperature increases with the Ti core radius. The trend agrees well with the theoretical phase diagram of bimetallic nanoparticles. In addition, the glass phase formation of Al–Ti nanoparticles for the fast cooling rate of 12 K/ps, and the crystal phase formation for the low cooling rate of 0.15 K/ps. The icosahedron structure is formed in the frozen 4366 Al–Ti atoms for the low cooling rate.
引文
[1]Djanarthany S,Viala J C and Bouix J 2001 Mater.Chem.Phys.72 301
[2]Niu H Z,Kong F T,Chen Y Y and Yang F 2011 J.Alloy.Comp.50910179
[3]Forouzanmehr N,Karimzadeh F and Enayati M H 2009 J.Alloy.Comp.471 93
[4]Vaucher S,Stir M,Ishizaki K,Catala-Civera J M and Nicula R 2011Thermochim.Acta 522 151
[5]Sun Y,Vajpai S K,Ameyama K and Ma C 2014 J.Alloy.Comp.585734
[6]Liu T,Zhang T W,Zhu M and Qin C G 2012 J.Nanopart.Res.14 738
[7]Sienkiewicz J,Kuroda S,Molak R M,Murakami H,Araki H,Takamori S and Kurzyd?owski K J 2014 Intermetallics 49 57
[8]Nogorani F S,Ashrafizadeh F and Saatchi A 2012 Surf.Coat.Tech.21097
[9]Garbacz H,Pouquet J M,Garc′?a-Lecina E,D′?az-Fuentes M,Wieci n′ski P,Martin R H,Wierzcho n′T and Kurzydlowski K J 2011 Surf.Coat.Tech.205 4433
[10]Ryu J R,Moon K II and Lee K S 2000 J.Alloy.Comp.296 157
[11]Patselov A,Greenberg B,Gladkovskii S,Lavrikov R and Borodin E2012 AASRI Procedia 3 107
[12]Li X W,Sun H F,Fang W B and Ding Y F 2011 Trans.Nonferrous Met.Soc.China 21 s338
[13]Zhou K,Wang H P and Wei B 2012 Chem.Phys.Lett.521 52
[14]Pei Q X,Lu C and Fu M W 2004 J.Phys.:Condens.Matter 16 4203
[15]Xie Z C,Gao T H,Guo X T,Qin X M and Xie Q 2014 J.Non-Cryst.Solid.394 16
[16]Kiselev S P and Zhirov E V 2014 Intermetallics 49 106
[17]Koizumi Y,Yoshiya M,Sugihara A and Minamino Y 2011 Philos.Mag.91 3685
[18]Tan X Q,Chen J,Zhi W and Brown J 2010 Physica B 405 3543
[19]Levchenko E V,Evteev A V,L o¨wisch G G,Belova I V and Murch G E2012 Intermetallics 22 193
[20]Levchenko E V,Evteev A V,Lorscheider T,Belova I V and Murch G E 2013 Comp.Mater.Sci.79 316
[21]Moon K II and Lee K S 1999 J.Alloy.Compd.291 312
[22]Bhattacharya P,Bellon P,Averback R S and Hales S J 2004 J.Alloy.Compd.368 187
[23]Shu S L,Qiu F,Tong C Z,Shan X N and Jiang Q C 2014 J.Alloy.Copmd.617 302
[24]Song P and Wen D 2010 J.Phys.Chem.C 114 8688
[25]Wen Y H,Huang R,Li C,Zhu Z Z and Sun S G 2012 J.Mater.Chem.22 7380
[26]Cheng D and Hou M 2010 Eur.Phys.J.B 74 379
[27]Huang R,Wen Y H,Shao G F,Zhu Z Z and Sun S G 2013 J.Phys.Chem.C 117 6896
[28]Huang R,Wen Y H,Shao G F and Sun S G 2013 J.Phys.Chem.C 1174278
[29]Cheng X L,Zhang J P,Zhang H and Zhao F 2013 J.Appl.Phys.114084310
[30]Plimpton S 1995 J.Comput.Phys.117 1
[31]Zope R R and Mishin Y 2003 Phys.Rev.B 68 024102
[32]Pezold J von,Dick A,Fria′k M and Neugebauer J 2010 Phys.Rev.B 81094203
[33]Qi Y,Cagin T,Johnson W L and Goddard W A 2001 J.Chem.Phys.115 385
[34]Cao B,Starace A K,Judd O H and Jarrold M F 2009 J.Am.Chem.Soc.131 2446
[35]Kambara M,Uenishi K and Kobayashi K F 2000 J.Mater.Sci.35 2897
[36]Li G J,Wang Q,Cao Y Z,Lu¨X,Li D G and He J C 2011 Acta Phys.Sin.60 093601(in Chinese)
[37]Wendt H R and Abraham F F 1978 Phys.Rev.Lett.41 1244
[38]Nam H S,Hwang N M,Yu B D and Yoom J K 2002 Phys.Rev.Lett.89275502