Chromium-Aluminum Binary Alloy Having Excellent Corrosion Resistance and Method of Manufacturing Thereof

Abstract

The present disclosure relates to a chromium-aluminum binary alloy with excellent corrosion resistance and a method of producing the same, and more particularly to a chromium-aluminum binary alloy with excellent corrosion resistance, including: 1 to 40% by weight of aluminum (Al), the balance of chromium (Cr), and other unavoidable impurities with respect to a total weight of the alloy, and a method of producing a chromium-aluminum binary alloy with excellent corrosion resistance, the method including: (Step 1) mixing and melting a raw material comprising: 1 to 40% by weight of aluminum (Al), the balance of chromium (Cr), and other unavoidable impurities with respect to a total weight of the alloy; and (Step 2) solution treating the alloy melted in Step 1. The chromium-aluminum binary alloy may be easily produced and has ductility, thus being highly applicable as a coating material for a material requiring high-temperature corrosion resistance and wear resistance.

Description

CROSS-REFERENCES TO RELATED APPLICATION[0001]This patent application claims the benefit of priority from Korean Patent Application No. 10-2014-0141522, filed on Oct. 20, 2014, the contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present disclosure relates to a chromium-aluminum binary alloy with excellent corrosion resistance and a method of producing the same, and more particularly, to a chromium-aluminum binary alloy including 1 to 40% by weight of aluminum and to a method of producing the same.[0004]2. Description of the Related Art[0005]A zirconium alloy material used as a core component of a fuel assembly in Japan's Fukushima accident generated a large amount of hydrogen by a very high corrosion reaction rate to act as the cause of a hydrogen explosion in a high-temperature oxidizing atmosphere in which coolant was lost and a temperature of a nuclear fuel was increased.[0006]From this fact, it was confirm...

AI Technical Summary

Benefits of technology

The patent text describes a new type of alloy made from chromium and aluminum that has excellent resistance to corrosion. The invention also includes a method for producing this alloy and a high-temperature environment structural material made from this alloy.

Problems solved by technology

From this fact, it was confirmed that when the current zirconium alloy material was used as a core material of a nuclear power plant, there was no big problem in a steady-state, but safety was not guaranteed in an accident-state.

That is, when a material in which oxidation is hardly generated is applied to the zirconium alloy or an oxidation-resistant coating material stable at a high-temperature environment of an accident-state is present on a zirconium alloy surface, an oxidation reaction is significantly suppressed to reduce hydrogen generation by the oxidation reaction, so that a risk of hydrogen explosion may be blocked.

However, these material technologies are favorable in a normal-state but unfavorable in an accident-state, and vise versa.

For example, a SiC / SiCf material is being evaluated to have excellent high-temperature strength and superior oxidation resistance, but to have drawbacks in that the material dissolution very quickly in a steady-state ambient and the production cost is very high.

The FeCrAl alloy has excellent corrosion resistance under steady and accident-states, but, due to a material characteristic, has a large neutron absorption cross-sectional area and a low tritium collection property, thus having a disadvantage in that the FeCrAl alloy is economically infeasible when being used in a steady operation.

The Zr—Mo-coated cladding tube is excellent in high temperature strength, but greatly increases a cost for producing the cladding as a trilayer and still has a lot of problems to be technically solved.

That is, when the FeCrAl alloy with excellent corrosion resistance is applied to the Zr-coated cladding tube, there are problems in which a composition of the coating material is changed by interdiffusion of Zr and Fe at a temperature of 950° C. or higher and a base material of the Zr cladding tube form a Zr—Fe-based intermetallic compound to be weakened.

However, the Zr-coated cladding tube is weak to an impact due to low ductility of the Cr layer and has a relatively low high-temperature oxidation resistance compared to the FeCrAl alloy.

However, since the FeCrAl material, due to a material characteristic thereof, has a large neutron absorption cross-sectional area and a low collection property of tritium generated in a nuclear fuel, the FeCrAl material is economically infeasible used in a steady operation, and has a problem in which a base material of the Zr cladding tube forms a Zr—Fe-based intermetallic compound to be weakened when the FeCrAl material is applied to the Zr cladding tube.

Thus, it is difficult to realize both safety and economic feasibility with a combination of materials and coating technologies reported so far, under a steady-state or an accident-state of nuclear power.

Images