A case study of complex metallic alloy phases: structure and disorder phenomena of Mg-Pd compounds

被引:31
作者
Makongo, JPA [1 ]
Prots, Y [1 ]
Burkhardt, U [1 ]
Niewa, R [1 ]
Kudla, C [1 ]
Kreiner, G [1 ]
机构
[1] Max Planck Inst Chem Phys Fester Stoffe, D-01187 Dresden, Germany
关键词
D O I
10.1080/14786430500269212
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
In order to achieve a deeper insight into the relation between the homogeneity range, crystal structure and disorder phenomena of complex metallic alloy phases (CMAs) we have redetermined the Mg-Pd phase diagram in the range 60-100 at.% Mg. The existence of the intermediate phases Mg6Pd (beta), Mg57Pd13 (gamma), Mg56.4Pd13.5 (delta), Mg306Pd77 (epsilon), Mg78.5Pd21.5 (zeta), Mg3Pd (eta), Mg5Pd2 (theta) and Mg2Pd (iota) has been reconfirmed. The first five of these are CMAs. The beta phase melts congruently whereas the CMAs gamma, delta, epsilon and zeta form in a cascade of peritectoid and peritectic reactions in a narrow window of approximately 30 degrees C and 3 at.%. It is assumed that the stability of the Mackay icosahedron plays an important role in the phase formation of these CMAs. However, the beta phase reveals an intricate pattern of disorder at the atomic positions of the Mackay icosahedron. Therefore, the concept of the stability of the Mackay cluster should be used only as a rule of thumb.
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页码:427 / 433
页数:7
相关论文
共 2 条
[1]  
Makongo JPA, 2004, MATER RES SOC SYMP P, V805, P61
[2]  
SAMSON S, 1972, ACTA CRYSTALL B-STRU, VB 28, P936, DOI 10.1107/S0567740872003437