Structure and Mechanical Properties of Electrolytic Chromium Coatings Deposited on the Inner Surface of Fuel Cladding Made of EP823-Sh Steel

The structure and some mechanical properties of electrolytic chromium coatings deposited on the inner surface of the fuel cladding made of EP823-Sh ferritic-martensitic steel were studied. It was shown that the optimal temperature of the electrolytic bath for deposition of hard dense coatings without cracks is 30–35°C at a current density of 0.15–0.18 A/cm2. At higher temperatures, finely dispersed columnar chromium crystals are deposited, texture appears, and microcracks are formed, which reduces the protective properties of the coating. Nanohardness, elastic modulus, elastic limit, ultimate relative deformation, tensile fracture limit, and abrasive wear resistance of the coatings are determined.