A method for preparing a high entropy alloy (HEA) structure includes the steps of: preparing an alloy by arc melting raw materials comprising five or more elements; drop casting the melted alloy into a cooled mold to form a bulk alloy; applying an external force against the bulk alloy to reshape the bulk alloy; and heat-treating the reshaped bulk alloy, wherein the bulk alloy is reshaped and/or heat-treated for manipulating the distribution of the microstructure therein. The present invention also relates to a high entropy alloy structure prepared by the method.

A method of producing a CoFe alloy strip is provided. The method comprises hot rolling a CoFe alloy to form a hot rolled strip, followed by quenching the strip from a temperature above 700° C. to a temperature of 200° C. The CoFe alloy comprises an order/disorder temperature T.sub.o/d and a ferritic/austenitic transformation temperature T.sub.α/γ, wherein T.sub.α/γ>T.sub.o/d. The method further comprises cold rolling the hot rolled strip, after cold rolling, continuous annealing the strip at a maximum temperature T.sub.1, wherein 500° C.<T.sub.1<T.sub.o/d, followed by cooling at a cooling rate R.sub.1 of at least 1 K/s in the temperature range of T.sub.1 to 500° C., and after continuous annealing, magnetic annealing the strip, or parts manufactured from the strip, at a temperature between 730° C. and T.sub.α/γ.

The present invention provides a cast product that can further enhance the stability of an alumina barrier layer and can exhibit further superior oxidation resistance, carburization resistance, nitriding resistance, corrosion resistance, and the like when used under a high-temperature atmosphere. The cast product according to the present invention is a cast product having an alumina barrier layer including an aluminum oxide on a surface of a matrix, and the aluminum oxide is (Al.sub.(1-x)M.sub.(x)).sub.2O.sub.3, where M is at least one of Cr, Ni, Si, and Fe, and x satisfies a relationship 0<x<0.5. Furthermore, the cast product according to the present invention is a cast product having an alumina barrier layer including an aluminum oxide on a surface of a matrix, and at least one of Cr, Ni, Si, and Fe forms a solid solution in the aluminum oxide, and at least one of Cr, Ni, Si, and Fe forming the solid solution with Al is contained so as to satisfy a relationship Al/(Cr+Ni+Si+Fe)≧2.0 in an atomic % ratio.

Methods are provided that include depositing a nickel-base superalloy powder including gamma nickel solid solution and gamma prime (Ni.sub.3Al) solid solution phases onto a seed crystal having a predetermined primary orientation, fully melting the powder and a portion of the seed crystal at a superliquidus temperature to form an initial layer having the predetermined primary orientation, heat treating the layer at subsolvus temperatures to precipitate gamma prime solid solution phase particles, depositing additional powder over the layer, melting the deposited powder and a portion of the initial layer at a superliquidus temperature to form a successive layer having the predetermined primary orientation, heat treating the layer at a subsolvus temperature to precipitate gamma prime solid solution phase particles, and repeating depositing additional powder, melting the additional powder and the portion of the successive layer at the superliquidus temperature, and heat treating the successive layer at a subsolvus temperature.

Methods are provided that include depositing a nickel-base superalloy powder including gamma nickel solid solution and gamma prime (Ni.sub.3Al) solid solution phases onto a seed crystal having a predetermined primary orientation, fully melting the powder and a portion of the seed crystal at a superliquidus temperature to form an initial layer having the predetermined primary orientation, heat treating the layer at subsolvus temperatures to precipitate gamma prime solid solution phase particles, depositing additional powder over the layer, melting the deposited powder and a portion of the initial layer at a superliquidus temperature to form a successive layer having the predetermined primary orientation, heat treating the layer at a subsolvus temperature to precipitate gamma prime solid solution phase particles, and repeating depositing additional powder, melting the additional powder and the portion of the successive layer at the superliquidus temperature, and heat treating the successive layer at a subsolvus temperature.

The present disclosure relates to new materials comprising Al, Co, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 6.7-11.4 wt. % Al, 5.0-48.0 wt. % Co, and 43.9-88.3 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, and combinations thereof. The new alloys may realize improved high temperature properties.

The present disclosure relates to new materials comprising Al, Co, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 6.7-11.4 wt. % Al, 5.0-48.0 wt. % Co, and 43.9-88.3 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, and combinations thereof. The new alloys may realize improved high temperature properties.

The present disclosure relates to new materials comprising Al, Co, Cr, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 2.2-8.6 wt. % Al, 4.9-65.0 wt. % Co, 4.3-42.0 wt. % Cr, and 4.8-88.6 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, the sigma phase, the bcc phase, and combinations thereof. The new alloys may realize improved high temperature properties.

The present disclosure relates to new materials comprising Al, Co, Cr, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 2.2-8.6 wt. % Al, 4.9-65.0 wt. % Co, 4.3-42.0 wt. % Cr, and 4.8-88.6 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, the sigma phase, the bcc phase, and combinations thereof. The new alloys may realize improved high temperature properties.

The present disclosure relates to new materials comprising Al, Co, Fe, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 4.4-11.4 wt. % Al, 4.9-42.2 wt. % Co, 4.6-28.9 wt. % Fe, and 44.1-86.1 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, and combinations thereof. The new alloys may realize improved high temperature properties.