8 results about "Atomic radius" patented technology

The invention relates to the technical field of high-entropy alloy model construction. The invention provides a simulation modeling method, system and equipment for a high-entropy alloy coating interface and a storage medium. The method comprises the following steps: determining element types, contents and basic structures of a high-entropy alloy system according to application requirements; a special quasi-random structure file is generated by adopting a Monte Carlo simulated annealing algorithm, and a surface model is constructed through format conversion and crystal face cutting; specific atom pairs needing to be preferentially considered are recognized based on the atomic radius and the enthalpy formation criterion, and a surface structure model containing the specific atom pairs is constructed by exchanging the positions of surface atoms and block atoms; constructing a matrix surface model according to the actual matrix material parameters; the two are combined, and coordinates are calculated by setting interface spacing and layer number parameters so as to construct a coating interface model. The problem that in existing numerical simulation of the high-entropy alloy coating interface, a microstructure model cannot be accurately established due to the fact that specific atoms are difficult to recognize and position is solved.

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.

A high-strength R-T-B rare earth permanent magnet having an amorphous grain boundary phase includes: 29.0 wt. %-34.0 wt. % of large-atomic-radius elements with the atomic radius r satisfying r≥0.16 nm, said large-atomic-radius elements comprising 0.1 wt. %-0.8 wt. % of Mf, and Mf being any one or two of Zr and Mg; 1.05 wt. %-1.65 wt. % of small-atomic-radius elements with r≤0.12 nm, said small-atomic-radius elements comprising 0.8 wt. %-1.1 wt. % of boron element, and the total content C1 of the small-atomic-radius elements satisfying 0.25 wt. %≤[C1]−[B]≤0.55 wt. %; and the balance being medium-atomic-radius elements with 0.12 nm<r<0.16 nm and impurities, said medium-atomic-radius elements at least comprising 60.0 wt. % of TM, the TM being at least one of Fe and Co, and the content of other medium-atomic-radius elements except said TM being ≥0.2 wt. %. In the present invention, the proportion of the amorphous grain boundary phase in the grain boundary phase of the magnet is increased to 20 vol. % or more, thereby improving the capability of resisting crack propagation of the grain boundary phase of the magnet, and manufacturing a high-strength R-T-B rare earth permanent magnet.

To provide an interlayer asymmetrically aligned multi-element MAX phase and MXene.SOLUTION: The disclosed MAX phase has a layered structure of M(n+1)AXn comprising a plurality of transition metal layers (where n is a natural number, and n and n+1 indicate the number of layers), wherein M comprises two or more transition metal elements, X comprises nitrogen or carbon, A comprises at least a first element and a second element that are different from each other and selected from Group 13 elements, Group 14 elements, Group 15 elements, and Group 16 elements, a difference in atomic radius between the first element and the second element is 0.1 Å or more, and among the transition metal layers, a first transition metal layer and a second transition metal layer corresponding to outermost layers opposed to each other have compositions different from each other, whereby the MAX phase and MXene have an interlayer asymmetrically aligned structure.SELECTED DRAWING: Figure 1

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.