The structural, dielectric and ferroelectric properties of Pb(Mg1/3Nb2/3)(0.9)Ti0.1O3 (PMNT) ceramics prepared with CuO as a sintering aid at various sintering temperatures between 950 degrees C and 1150 degrees C are investigated. The lattice parameters slightly increase with the sintering temperature >1050 degrees C. A significant increase in the grain size is observed when the sintering temperature is increased from 1000 degrees C to 1050 degrees C. The maximum dielectric constant reaches the highest value of similar to 22,000 for the ceramic sintered at 1050 degrees C. For the ceramics sintered at >1050 degrees C, the temperature of maximum dielectric constant and the diffuseness parameters tend to increase with the increasing sintering temperature. The optimal sintering temperature for this ceramic is 1050 degrees C, which displays significant improvements in ferroelectric properties at room temperature, i.e. the increase in the remanent polarization and the ferroelectric loop squareness. (C) 2013 Elsevier B.V. All rights reserved.