Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

A method of forming an airfoil includes the steps of depositing material to form an airfoil in a first layer, and then depositing material in a second layer on the first layer. The first and second layers have distinct densities. An airfoil is also disclosed. The method provides powerful design advantages.

A method of forming an airfoil includes the steps of depositing material to form an airfoil in a first layer, and then depositing material in a second layer on the first layer. The first and second layers have distinct densities. An airfoil is also disclosed. The method provides powerful design advantages.

A composite can include a substrate and a conversion coating overlying the substrate and comprising at least one of a zirconium oxide, a hafnium oxide, or a combination thereof. The conversion coating can be formed from a zirconia or hafnia-based complex obtained by reacting at least one of a zirconium ion source, a hafnium ion source, or a combination thereof, with a chelating compound in a reaction and another chelating compound in another reaction.

A composite can include a substrate and a conversion coating overlying the substrate and comprising at least one of a zirconium oxide, a hafnium oxide, or a combination thereof. The conversion coating can be formed from a zirconia or hafnia-based complex obtained by reacting at least one of a zirconium ion source, a hafnium ion source, or a combination thereof, with a chelating compound in a reaction and another chelating compound in another reaction.

A method for the inner-contour passivation of steel surfaces of a nuclear reactor consists in filling a first contour of a nuclear reactor with a liquid metal coolant, introducing a reagent into the liquid metal coolant, said reagent interacting with the material of elements of the first contour, forming a protective film, and heating the liquid metal coolant, having the reagent introduced therein, to a temperature allowing for conditions for forming the protective film. The liquid metal coolant having the reagent introduced therein is kept at said temperature until a continuous protective film is formed on the surface of the material of the elements of the first contour. The liquid metal coolant having reagent introduced therein is heated by means of the friction thereof against rotating vanes of a vane pump, which is submerged in the liquid metal coolant. The present invention thus provides for a simpler passivation process, a more reliable passivation mode, an increase in the safety thereof and a simpler control over the process of passivation of steel surfaces.

The invention relates to the field of nuclear technology, and specifically to a method for the in situ passivation of steel surfaces. The method consists in installing, in a position intended for a regular core, a core simulator in the form of a model of the core, which models the shape thereof, the relative position of the core components, and also the mass characteristics thereof; next, the reactor is filled with a heavy liquid metal heat transfer medium, the heat transfer medium is heated to a temperature which provides for the conditions of passivation, and in situ passivation is carried out in two stages, the first of which includes an isothermal passivation mode in conformity with the conditions determined for this stage, and the second mode includes non-isothermal passivation, which is carried out under different conditions, after which the core simulator is removed and the regular core is installed in the place thereof. The method provides for the corrosion-resistance of steel elements in a heavy liquid metal heat transfer medium environment and permits a decrease in the maximum rate of oxygen consumption during the initial period of operation of a nuclear actor.

The invention relates to the field of nuclear technology, and specifically to a method for the in situ passivation of steel surfaces. The method consists in installing, in a position intended for a regular core, a core simulator in the form of a model of the core, which models the shape thereof, the relative position of the core components, and also the mass characteristics thereof; next, the reactor is filled with a heavy liquid metal heat transfer medium, the heat transfer medium is heated to a temperature which provides for the conditions of passivation, and in situ passivation is carried out in two stages, the first of which includes an isothermal passivation mode in conformity with the conditions determined for this stage, and the second mode includes non-isothermal passivation, which is carried out under different conditions, after which the core simulator is removed and the regular core is installed in the place thereof. The method provides for the corrosion-resistance of steel elements in a heavy liquid metal heat transfer medium environment and permits a decrease in the maximum rate of oxygen consumption during the initial period of operation of a nuclear actor.

A composite can include a substrate and a conversion coating overlying the substrate and comprising at least one of a zirconium oxide, a hafnium oxide, or a combination thereof. The conversion coating can be formed from a zirconia or hafnia-based complex obtained by reacting at least one of a zirconium ion source, a hafnium ion source, or a combination thereof, with a chelating compound in a reaction and another chelating compound in another reaction.