Kinetics of Anodic Film Growth on Zr-4 in Ammonium Tartrate

Abstract

The kinetics of anodic film growth on Zr-4 in 0.05 M ammonium tartrate has been studied at different current densities at room temperature under galvano static condition. The kinetic parameters like rate of film formation(dV/dt), ionic current density(ii),current efficiency() and field of formation(F) were calculated. Using Cabrera-Mott theory the kinetic parameters such as half- jump distance(a), height of the energy barrier(W) were deduced. It is also established an exponential relation between ionic current density(ii) and field of formation(F). 2 area prepared from 0.1mm thick sheet supplied by Nuclear Fuel Complex, Hyderabad. The nominal purity of Zr-4 was Sn(1.44%), Fe(0.13%), Cr(0.07%) and remaining Zirconium. These specimens were chemically polished in a mixture of 1 part of HF(49%), 3 parts of HNO3(70%) and 3 parts of distill water and dried. The specimens were suspended vertically in the cell containing 0.05 M ammonium tartrate electrolyte. The anode used was chemically polished Zr-4 and the cathode was Platinum foil of 20 cm 2 superficial area to make the double layer capacitance as large as possible.