13 results about "Single crystal superalloy" patented technology

The application discloses a kind of second generation nickel-based single crystal superalloy recrystallization defect simulation and control method.The method steps are: according to sample preparation wax mold, after sand blasting, dry baking, manufacture ceramic shell;Through directional solidification preparation second generation nickel-based single crystal superalloy sample, control pulling speed, holding temperature and temperature gradient and other parameters;According to service condition preparation sample, simulate stress loading, in combination with heat treatment simulate actual service environment;Using electron backscattering diffraction and X-CT imaging, characterize recrystallization grain orientation distribution, three-dimensional morphology, content and thickness.Process parameter-defect characteristic mapping relationship is established, the stress distribution characteristics during preparation are clarified, the ceramic shell and preparation process are feedback controlled, and the control of recrystallization defects is realized.The application simulates the actual service environment of high-temperature alloy blade, and restores the performance of recrystallization defect sample in actual service environment.The application provides an experimental reproduction method and effective process control strategy for recrystallization defect research.

The application discloses a design method and system of a single-crystal high-temperature alloy solid solution heat treatment system, relates to the cross technical field of numerical simulation and material processing, and comprises the following steps: based on the relationship between element concentration and solidus temperature, determining the solidus temperature distribution of a cast single-crystal high-temperature alloy sample according to the element concentration distribution extracted from the cast single-crystal high-temperature alloy sample; adopting a phase field method to simulate solid solution heat treatment of the cast single-crystal high-temperature alloy sample, so as to obtain the element concentration distribution under the initial melting temperature and heat preservation for one simulation time step, and mark the element concentration distribution after treatment as the element concentration distribution, and determine the segregation coefficient of each element; when the segregation coefficients of all elements are within a preset range, marking all initial melting temperatures and corresponding current simulation times as heat treatment simulation results, and then determining the actual solid solution heat treatment system of the cast single-crystal high-temperature alloy sample. The application has the advantages of short time consumption, high efficiency and low cost.

The application discloses a material for connecting single-crystal superalloy and polycrystal superalloy and a preparation and use method thereof, and the material comprises low-melting-point Ni-Ti alloy powder and high-melting-point Ni-based alloy powder. The material can realize rapid high-performance connection of the single-crystal superalloy and the polycrystal superalloy. The application belongs to the technical field of alloy material connection.

This invention relates to the field of high-temperature alloy technology, specifically to a method for improving the microstructure stability of single-crystal high-temperature alloys by controlling the nitrogen (N) content. The content of refractory elements in single-crystal high-temperature alloys increases with increasing heat resistance, leading to decreased microstructure stability and increased precipitation of topologically close-packed (TCP) phases, resulting in decreased mechanical properties. Based on the influence of N on the TCP phase precipitation behavior in high-temperature alloys, this invention proposes a method to effectively improve the microstructure stability of single-crystal high-temperature alloys by controlling the N content. By adding a certain amount of CrN or AlN during directional solidification to ensure an N mass content of 15-30 ppm in the single-crystal alloy, the amount of TCP phase precipitates in the alloy microstructure is significantly reduced after long-term high-temperature heat exposure, and the microstructure stability of the single-crystal alloy is significantly improved. This invention employs a simple and feasible method to effectively improve the microstructure stability of single-crystal high-temperature alloys.

The present application relates to single crystal alloy casting defect control technical field, especially to a kind of trace element / microelement carbon reduction method for reducing micro-pore in the casting process of nickel-based single crystal superalloy.The present application is aimed at different alloy system, and target carbon content is determined by thermodynamics-solidification simulation, so that carbide starts to precipitate when solid phase mass fraction is 80%~90% during solidification, thereby promoting interdendritic residual melt feeding at the end of solidification when feeding channel is not completely closed, and the purpose of significantly reducing the porosity of single crystal casting is achieved.The present application is not limited to all alloys with fixed content range, but determines the corresponding carbon content according to the solidification characteristics of each alloy system, so it can be applied to single crystal alloys of different systems.

The application belongs to the field of metal material processing, and discloses a method for homogenizing nickel-based single crystal superalloy by using pulse current, wherein a gradient pulse current with two or more stages is applied to the as-cast nickel-based single crystal superalloy. The single crystal superalloy can be quickly homogenized by applying the gradient pulse current, and the gamma / gamma prime eutectic structure and carbide can be eliminated, and the dendritic segregation can be obviously improved.

A method for detecting the recrystallization of a single-crystal superalloy blade, characterized in that it comprises: establishing a database for the recrystallization of single-crystal superalloys; performing creep tests under preset conditions on recrystallized single-crystal superalloy creep specimens with different recrystallization area fractions and maximum recrystallization depths under the same test conditions in order to obtain the recrystallization damage tolerance of the corresponding single-crystal superalloy and its corresponding blades under corresponding operating conditions;Obtaining the relevant parameters of the coordinate information of the deformation location of the single-crystal superalloy blade under test and entering these parameters into the database for the recrystallization of single-crystal superalloys in order to obtain the recrystallization area fraction of the cross-section and the maximum recrystallization depth at the deformation location of the single-crystal superalloy blade; Assessing whether the obtained recrystallization area fraction of the cross-section and the maximum recrystallization depth at the deformation location are smaller than their corresponding recrystallization damage tolerance, whereby, if so, the detection result for the deformation location is considered reliable and, otherwise, the detection result for the deformation location is considered unreliable.

This application discloses a fatigue life prediction method for single-crystal superalloys based on wear mark features, aiming to provide more accurate fatigue life prediction for single-crystal materials. The method includes: acquiring three-dimensional surface morphology data of the target single-crystal material to generate a two-dimensional pseudo-color planar image; extracting wear mark features from the two-dimensional pseudo-color planar image to calculate the surface wear mark equivalent damage factor value, and substituting it into a preset fatigue failure correction equation to calculate the initial fatigue life prediction result; the preset fatigue failure correction equation is obtained by introducing the surface wear mark equivalent damage factor into the Paris equation, where the surface wear mark equivalent damage factor is used to correct the surface defect equivalent projected area of ​​the stress intensity factor in the Paris equation; if the initial fatigue life prediction result is normal, it is taken as the true fatigue life prediction result; if the initial fatigue life prediction result is abnormal, it is processed using a preset compensation learning model to obtain the true fatigue life prediction result.

This invention belongs to the field of single-crystal high-temperature alloy casting, specifically a comprehensive evaluation system and optimization method for the casting processability of single-crystal blades. The method includes the following steps: constructing a module for evaluating casting processability, which comprises at least one single-crystal casting and its associated structures; simulating the directional solidification process of the casting module through numerical simulation to obtain the physical field distribution information of the casting process; identifying casting defect risk areas based on the physical field distribution information and evaluating the casting process performance; optimizing and adjusting the module structural parameters and process parameters based on the evaluation results; comparing the optimized scheme with experimental data to establish a correlation mechanism between module design, casting geometry, and alloy system, thereby achieving iterative optimization and solidification of the casting process. This invention improves the reliability of single-crystal blade casting processes and reduces trial-and-error costs through simplified module design, multi-physics simulation and defect identification, multi-objective optimization, and experimental feedback learning.

This invention discloses a platinum-aluminum protective coating on the surface of DD6 single-crystal superalloy and its preparation method, belonging to the field of high-temperature protective coating technology. The platinum-aluminum coating is formed on the surface of a DD6 nickel-based single-crystal superalloy substrate, consisting of an interdiffusion layer and an aluminized layer from the inside out. The preparation process includes: pretreating the DD6 alloy substrate; preparing a platinum layer with a thickness of 3-4 μm on the substrate surface using electroplating; performing a first vacuum heat treatment under a protective atmosphere to allow the platinum layer to interdiffused with the substrate to form a platinum-modified layer; then preparing an aluminized layer on the surface of the platinum-modified layer using a vapor-phase aluminizing method; and finally performing a second vacuum diffusion treatment under a protective atmosphere to obtain a dense coating. The platinum-aluminum coating prepared by this invention has strong adhesion to the substrate and a controllable microstructure, significantly improving the oxidation resistance of DD6 alloy under high-temperature oxidizing environments, and is suitable for the protection of high-temperature hot-end components such as turbine blades of aero-engines.

The present application relates to the technical field of nickel-based superalloy, and particularly relates to a trace / microelement regulation method for optimizing the creep and oxidation performance of nickel-based single crystal superalloy. The trace / microelements in the optimized nickel-based single crystal superalloy satisfy the following conditions: Hf 1000-2000ppm; C: 50-150ppm; the total content of C+B is not more than 150ppm; Ce: 0 or 20-100ppm, Y: 0 or 20-100ppm, and 0 C+Y≤3 / 4 of the content of C element; and the total content of C, B, Hf, Ce and Y is 1000-2500ppm. The present application controls the added content of trace / microelements C, B, Hf, Ce and Y in the nickel-based single crystal superalloy, optimizes the micro-area distribution of the elements in the alloy structure, and thus improves the comprehensive service performance of the alloy in high-temperature creep and oxidation.

This invention relates to the field of aero-engine testing technology and discloses a universal fixture for high-temperature, high-cycle vibration fatigue testing of irregularly clamped blades. The fixture consists of a cylindrical main structure and a clamping structure. Finite element simulation design ensures that the resonant frequency is close to the blade's resonant frequency, amplifying the vibration stress. The fixture is made of high-temperature alloys and single-crystal high-temperature alloys, and the fasteners are high-temperature resistant hexagonal bolts, the diameter and number of which can be adjusted according to the blade shape. The fixture is easy to operate and suitable for high-temperature and room-temperature vibration fatigue testing. In one embodiment, the fixture is equipped with a mounting platform and a locking system to achieve automatic positioning, fixing, and convenient removal of the blade clamping end, improving testing efficiency. In another embodiment, the hydraulic fixture system adopts a central cylinder and single-cylinder design, using hydraulic fluid to clamp the blade. Different hydraulic fluid media can be selected according to the testing environment, such as liquid silicone at 800 degrees Celsius.

The present application relates to a kind of second generation nickel-based single crystal superalloy stripe defect physical simulation method.The method steps are as follows: preparing wax mould of target sample and setting inducing particle on surface, then sand blasting and hanging slurry, dry baking, manufacturing ceramic shell containing inducing particle;Second generation nickel-based single crystal superalloy sample is prepared based on directional solidification process, inducing particle is introduced into shell, and the formation of stripe defect is induced by controlling pulling speed, holding temperature and temperature gradient;Macrostructure and orientation deviation angle, spatial distribution and three-dimensional morphology of stripe defect are characterized by chemical etching combined with electron backscatter diffraction and synchrotron radiation three-dimensional imaging technology;Based on thermodynamic calculation and finite element numerical simulation, the mapping relationship between process parameters and defect characteristics is established.The present application realizes the controllable preparation and high-precision characterization of stripe defect, and clarifies its formation mechanism and influence on mechanical properties, which provides systematic experimental and theoretical guidance for improving the quality of single crystal superalloy castings.