Iron-chromium-aluminum alloy and preparation method and application thereof

The invention belongs to the technical field of steel smelting, and particularly relates to an iron-chromium-aluminum alloy and a preparation method and application thereof. The preparation method of the iron-chromium-aluminum alloy, provided by the invention, comprises the following steps: (1) proportioning returned chromium steel, high-carbon ferrochrome, carbon scrap steel and/or returned scrap steel of the steel grade, and melting by adopting an intermediate frequency furnace; (2) adding the molten steel into an AOD furnace, and sequentially carrying out decarburization, reduction, denitrification, aluminum alloying and titanium alloying; wherein in the decarburization process, chromium steel is added for increasing steel; (3) before tapping of the AOD furnace, emptying a steel ladle with argon, and meanwhile, forming argon protection at a furnace mouth by blowing argon with a side gun in the tapping process; (4) transferring the molten steel into an LF furnace, and sequentially carrying out temperature a