Rhodium, Iridium, Rhutenium, Osmium, and their Alloys

Rhodium, Iridium, Rhutenium, Osmium, and their Alloys 

Production. Rhodium is produced as powder and sponge by chemical reduction or thermal decomposition of the chloro-ammonia complex (NHjlsIRHCl ]. Bars, rods, and wires are produced by powder compacting and extrusion, while coatings are produced galvanically, by evaporation or by sputtering. 

Phases and Phase Equilibria. Selected phase diagrams of Rh are shown in Fig. 3.1-301a-c. Rhodium forms continuous solid solutions with Fe, Co, Ni, Ir, Pd, and Pt. Miscibility gaps exist in alloys with Fe, Co, Ni, Cu, Ag, Au, Pd, Pt, Ru, and Os. Thermo-d3mamic data are given in Table 3.1-236 (see also 

T = Temperature, c = specific heat capacity, S = Entrtyy, H = Enthalpy, G = free Enthalpy,  

Metals I 1.10 Noble Metals and Noble Metal Alloys 387 

The compositions and crystal structures of intermediate compounds are shown in Table 3.1-237 (see Table 3.1-197 for superlattice structures). 

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