Phase intra rare earth binary alloys

Gschneidner Jr., K.A., and Calderwood, EW. (1986) Intra-rare earth binary alloys phase relationships, lattice parameters and systematics. In Handbook on the Physics and Chemistry of Rare Earths, eds. Gschneidner Jr., K.A. and Eyring, L. (North-Holland, Amsterdam), Vol. 8, p. 1. 

K.A. Gschneidner Jr and F.W. Calderwood, Intra rare earth binary alloys phase relationships, lattice parameters and systematics 1... 

Discovery of the unique beautifiilly complex magnetic structures of the heavy lanthanide metals Discovery of the existence of the Sm(6)-phase in intra rare earth binary alloys... 

This paper is dedicated to the memory of Professor Frank H. Spedding, Iowa State University, who died on December 15, 1984 at the age of 82. It is especially appropriate to the subject of this paper because a fair fraction of his many scientific endeavors was devoted to the study of the rare earth metals—especially their preparation, properties and alloying behavior of the intra rare earth binary alloys. His contributions (along with his many collaborators) in this area include the first to prepare metallic Sm metal the determination of its unique crystal structure the discovery of the Sm-type structure in an intermediate alloy phase formed by a light and a heavy lanthanide the first to ascertain that the crystal structure of the high temperature phase was bcc and the first to show that there is no detectable separation between liquidus and solidus (< 1°C) in binary alloy systems of the lanthanide metals that have atomic numbers within four of each other. 

The known phase relationships, crystallographic and thermodynamic data of the known rare earth binary phase diagrams have been critically evaluated. The intra rare earth binary alloy systems will be reported in order of increasing atomic number with the exception of scandium and yttrium, which will follow lutetium in that order. The first system to be considered is lanthanum-cerium (atomic numbers 57 and 58) followed by lanthanum-praseodymium (atomic numbers 57 and 59), etc. Following... 

Lundin (1970), in an investigation of the formation of samarium-type structure in intra rare earth binary alloys included six compositions in the lanthanum-scandium system ranging from 10 to 85at% La. Lundin prepared his alloys using 99.8(wt )% pure lanthanum metal (major impurities, 330 ppm other rare earths, 510 ppm O, 50 ppm each Si, Mg and Zn) and 99 -F (wt )% pure scandium for which there were no details given on the impurities. Lundin found two-phase inuniscibility at low temperatures in the lanthanum-scandium system and, since no samarium-type structure was found, he concluded that scandium behaves more like the neighboring transition elements than it does as a rare earth metal. 

Fig. 122. Isothermal sections of the generalized intra rare earth binary alloy phase diagram from 0 to 4 GPa (a) 200, (b) 400, (c) 600, (d) 700, (e) 800,...

As pointed out in the introduction, the majority of the intra-rare-earth, aetinide-rare earth and intra-actinide binary alloys do not possess any intermetallic compounds in the solid state (the exceptions will be pointed out later). The phase diagrams generally exhibit complete or extended solid solutions depending of course on the respective crystalline structures of the components. The allotropic forms of rare earths and actinides (Gschneidner 1990b) are presented in fig. 63 with the purpose of making the following more understandable. 

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