EFFECTS OF MELT CHEMISTRY AND PLATINUM DOPING IN THE REFINEMENT OF Y2BA1CU1OY PARTICLES FOR THE SYSTEM Y-BA-CU-O

Effects of melt chemistry and platinum doping in the refinement of Y2B a1Cu1Oy(211) particles were investigated for the system Y-Ba-Cu-O. The shapes of the 211 particles in the present study changed from needlel ike in a (CuO + BaCuO) melt to nearly spherical in a CuO melt, Platinu m plays a small role in the growth inhibition of 211 particles, Barium atoms clearly had no effect on the role of Pt in refining 211 particl es, and Pt was found to affect the refinement as an elementary atom ra ther than as part of a Pt-related compound. The main role of Pt in the refinement process for the system Y-Ba-Cu-O seems to lie in changing the interfacial energy of the 211 particles.