Effect of Ca substitutions on the properties of YBa2Cu3O6+dEffect of Ca substitutions on the properties of YBa2Cu3O6+d Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2015-12-021994enWe study the effect of Ca substitutions on the structural and superconducting properties of the system of nominal composition YCaFull-size image (<1 K)Ba2−xCu3O6+d. The system remains superconducting up to x=1.00 and the critical temperatures vary between 92 and 80K. A new, non superconducting phase of stoichiometry Y1.14Ca1.58Cu3.27O6.45 appears with concentrations that increase with the nominal concentration of Ca. For x=0.80 and x=1.00 we observe a substitution of the Ba with Ca in crystallites of the form YBa1.8Ca0.2Cu3O6.5.http://creativecommons.org/licenses/by/4.0/Physica C: Superconductivity235-240375-376 Perdikatsis Vasilis Περδικατσης Βασιλης O. Papageorgiou M. Calamiotou G. A. Soifer Th. Leventouri Elsevier