5 results about "Atomic radius" patented technology

A composition comprising a rare earth-doped zirconium / hafnium oxide is provided that has a defect-fluorite structure or a pyrochlore structure. The rare earth-doped zirconium / hafnium oxide has a formula: (Ln1aLn2aLn3aLn4aLn5b)2M2O7 where each of Ln1, Ln2, Ln3, Ln4, and Ln5 is a different rare earth element such that Ln1 and M have a first atomic radius ratio that is 1.35 to 1.45, Ln2 and M have a second atomic radius ratio that is 1.35 to 1.45, Ln3 and M have a third atomic radius ratio that is 1.46 to 1.78, and Ln4 and M have a fourth radius ratio that is 1.46 to 1.78; a is 0.2 or 0.25; b is 0.2 when a is 0.2, and b is 0 when a is 0.25; and M is Zr, Hf, or a mixture thereof. Methods of forming a coating that includes this composition, along with the resulting coated components, are also provided.

The invention relates to a component design method of a ThMn12 type rare earth iron-based alloy, which comprises the following steps: establishing a SmFe12-zNz crystal structure model, N being a transition metal element with an atomic radius greater than or equal to 125pm; based on a crystal structure model, RE and M are substituted according to a chemical general formula Sm < 1-x > RE < x > Fe < 12-y-z > N < z > M < y > to construct a simulated alloy, RE is a rare earth element, and M is an element different from N; the formation energy of the simulated alloy is calculated with the standard that the formation energy of the simulated alloy is smaller than the formation energy of the crystal structure model, the anisotropy field HA1 of the simulated alloy is calculated with the anisotropy field HA2 of the crystal structure model, and the intrinsic fault interface energy and the twin crystal interface energy are calculated with the standard that HA1-HA2 is larger than or equal to-1.02 T; x and y are determined on the basis that the intrinsic fault interface energy of the simulated alloy is larger than or equal to 65 mJ / m < 2 > and the twin crystal interface energy of the simulated alloy is larger than or equal to 60 mJ / m < 2 >, the components of the ThMn12 type rare earth iron-based alloy are obtained, and when the ThMn12 type rare earth iron-based alloy is used for preparing a ThMn12 type rare earth permanent magnet, twin crystal formation can be inhibited, and the coercive force can be improved.

Coating components having a layer with a composition comprising a rare earth-doped zirconium / hafnium oxide are provided. The rare earth-doped zirconium / hafnium oxide has a formula: (Ln1aLn2aLn3aLn4aLn5b)2M2O7 where each of Ln1, Ln2, Ln3, Ln4, and Ln5 is a different rare earth element such that Ln1 and M have a first atomic radius ratio that is 1.35 to 1.45, Ln2 and M have a second atomic radius ratio that is 1.35 to 1.45, Ln3 and M have a third atomic radius ratio that is 1.46 to 1.78, and Ln4 and M have a fourth radius ratio that is 1.46 to 1.78; a is 0.2 or 0.25; b is 0.2 when a is 0.2, and b is 0 when a is 0.25; and M is Zr, Hf, or a mixture thereof. Methods of forming a coating that includes this composition, along with the resulting coated components, are also provided.

The invention belongs to the technical field of metal material processing, and relates to a TiVNbHfZrAl refractory high-entropy alloy and a preparation method and application thereof, a Ti-V-Nb-Hf matrix is selected based on the lattice distortion effect, the radius of a V atom is 1.316, the radius of an Hf atom is 1.578, the lattice distortion effect in the alloy is caused, and the strength of the alloy is improved. On the basis of the matrix, the Zr element is introduced, and due to the fact that Zr atoms have the maximum atomic radius of 1.603 in the elements, local lattice distortion of the alloy is regulated and controlled. The Al element is introduced, and due to the negative mixing enthalpy effect between the Al element and other component elements, the effect of strengthening the acting force between atoms is achieved. After the TiVNbHfZrAl system is determined, the atomic size difference, the mixing enthalpy and the mixing entropy of the refractory high-entropy alloy are comprehensively considered, and it is ensured that a stable single-phase body-centered cubic structure and an atomic-scale component fluctuation structure are formed by controlling the atomic proportion.

This invention belongs to the field of metallic materials technology, specifically a TiZrMo-based refractory high-entropy alloy and its preparation method. The refractory high-entropy alloy is composed of any two of Al, Cr, and Nb, and Ti, Zr, and Mo. The atomic radius difference δ of the refractory high-entropy alloy is ≤6.6%, the alloy entropy enthalpy ratio Ω is ≥1.1, and the mixing enthalpy ΔH is... mix The energy density ranges from -18.0 to 4.0 kJ / mol, and the vacancy electron concentration (VEC) is <6.87. Furthermore, the preparation method of this invention has the advantages of simple steps, easily controllable composition, high production efficiency, and near-net-shape forming. The prepared refractory high-entropy alloy has a stable microstructure and a density of less than 7.00 g / cm³. 3 It has a Vickers hardness greater than 1400 HV, a room temperature compressive strength consistently above 980 MPa, an elongation at break greater than 10.8%, and an oxidation weight gain of less than 15.00 mg / cm³ at 800℃ for 12 hours. 2 It is low in cost and easy to apply on a large scale in industrial applications.