Microstructure of CuFeS 2–δ –CuInS 2 alloys

Two series of alloys of the (CuFeS 2–δ ) 1–x (CuInS 2 ) x system with molar part of CuInS 2 x = 0.01, 0.03, 0.125, 0.25, 0.375, 0.50, 0.625, 0.75, 0.95, 0.97 and 0.99 and δ being 0 and 0.10 were prepared from the CuFeS 2–δ and CuInS 2 starting ternary compounds. The samples were investigated by micro structural optics using freshly‐polished samples and XRPD. The studies confirmed two phase coexistences with microstructures dependent on the chemical composition. The geometric‐oriented arrangement of the α‐phase with the structure of CuInS 2 is found in the (CuFeS 2–δ ) 1–x (CuInS 2 ) x system up to x equalling 0.50. It was established that the solvus of CuFeS 2–δ exceeds 0.05 molar parts of CuInS 2 , while the solvus of CuInS 2 does not exceed 0.03 molar parts of CuFeS 2–δ . Additionally, stoichiometric composition of CuFeS 2 exhibits a mixture of 3 coexisting phases of CuFeS 2–δ , with δ from 0.14 to 0.28, bornite Cu 5 FeS 4 and pyrrhotite Fe 1–x S. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)