34 results about "Solidification microstructure" patented technology

The invention provides a multi-scale simulation method for high-fidelity selective laser melting forming and phase field-lattice Boltzmann coupling, and belongs to the technical field of selective laser melting numerical simulation. The method comprises the specific steps that a selective laser melting powder laying process model is constructed based on a discrete element method, and a randomly stacked powder bed model is obtained; a high-fidelity selective laser melting forming thermal fluid dynamic model is established, and macroscopic temperature distribution and flow field distribution of a molten pool are simulated; establishing a phase field model-lattice Boltzmann coupling model; and extracting temperature gradient, solidification velocity and melt flow velocity data of local positions of the boundary of the steady-state molten pool, and simulating solidification structure evolution under flowing of molten metal in the molten pool by taking the data as initial conditions of the phase field-lattice Boltzmann coupling model. According to the method, through high-fidelity multi-scale simulation, the relation between the process parameters and the microstructure is established more comprehensively, and reliable numerical support is provided for selective laser melting process optimization and microstructure prediction.

The invention provides an Al-RE rare earth alloy powder fuel forming an oxygen diffusion channel at a grain boundary, which is characterized in that a rare earth intermediate alloy Al-RE is added into a pure Al melt, alloying is carried out, and a solidification structure capable of diffusing oxygen atoms is formed after supersonic atomization of an inert gas atomization system, non-equilibrium cooling and staged treatment. In the high-temperature oxidation environment, the rare earth alloy powder fuel is oxidized, meanwhile, the grain boundary also starts to be oxidized, oxygen is diffused from the surface of the powder to the interior, an oxygen diffusion channel and a microstructure are formed through grain boundary oxidation, and complete oxidation combustion is achieved. The micron-sized powder fuel with the oxygen diffusion channel formed at the crystal boundary in the alloy powder fuel is low in production cost and easy to store, and has the advantages of reaction characteristics of nano-particle powder and high combustion efficiency. And due to the existence of an oxygen diffusion channel in the powder, internal crystal grains can be oxidized to a great extent, and almost no unburned residue exists, so that the combustion efficiency and the economic benefit of the fuel are improved, and the propelling capacity of the fuel is also greatly improved.

The invention relates to the technical field of die-casting aluminum alloys, in particular to a design method of an Al-Si-Mg-Cu heat-treatment-free die-casting aluminum alloy, a storage medium and equipment. The method comprises the following steps: establishing a thermodynamic database of an Al-Si-Mg-Cu quaternary system rich in an Al end; the solidification structure information of the Al-Si-Mg-Cu alloy is obtained; data corresponding to the input features and the output features are adopted to train a Gaussian regression model, and when R2 is larger than or equal to 0.9, training is completed; and the optimal component point in the preset alloy component content range is screened out. A computer program instruction is stored in the storage medium; the apparatus includes at least one processor, at least one memory, and computer program instructions stored in the memory; the method is implemented when computer program instructions are executed by a processor. According to the method, the optimal component point within the preset alloy component content range can be quickly screened out, and the design of the novel high-performance heat-treatment-free die-casting aluminum alloy is accelerated.

This invention discloses a method for controlling the uniformity of gear steel microstructure, including hot metal desulfurization and vanadium extraction, semi-steel converter smelting, LF refining, RH refining, and continuous casting processes. The method controls the solidification process of the molten steel in the molten pool during continuous casting, ensuring solidification is completed within a 1 / 4 arc-shaped region of the slab, and implementing a specified cooling and solidification control process. This method effectively improves the macroscopic solute concentration uniformity in all directions of the cross-section of the gear steel continuous casting slab, improves the regional symmetry of the solidified microstructure, and promotes more uniform phase transformation and stress distribution in the gear microstructure during gear processing and subsequent heat treatment. The range of distance between the equiaxed crystal zone boundary and the slab surface is reduced from 30-40 mm to 10-15 mm. After rolling into a round bar, the range of distance between the equiaxed crystal trace zone boundary and the round bar surface is controlled to ≤5 mm, and the range of solute segregation (circumferential) at the same radial distance from the surface of the round bar is ≤0.02. The resulting gear steel grain size stabilizes from grade 6.0-7.0 to grade 7.0.

This invention discloses a method for improving the dimorphic eutectic in SuperDyma alloys. The mass percentages of the components in the alloy are: Al: 11%, Mg: 3%, Si: 0.2%, B: 0.06-0.09%, with the remainder being Zn. First, SuperDyma alloys are obtained by casting using different cooling methods. The alloy liquid cooled using a copper mold exhibits the most uniform solidification structure, with a significant improvement in dimorphic eutectic. By adding B element to the SuperDyma alloy through alloying, the solidification structure is refined, further improving the dimorphic eutectic phenomenon and consequently enhancing the alloy's corrosion resistance.

The invention discloses a nickel-based high-temperature alloy powder particle size and solidification structure optimization method, which comprises the following steps of: obtaining a corresponding relation between different particle sizes and cooling rates in a continuous atomization process window through a simulation step, carrying out microscopic structure characterization on powder with different particle size groups through an experiment, and obtaining experimental data of a solidification structure; and coupling results of the simulation step and the experiment step, establishing a quantitative mapping relation model among the particle size, the cooling rate and the solidification assembly, based on the quantitative mapping relation model, taking a target solidification structure as input, carrying out backstepping to obtain target particle size distribution and corresponding atomization process parameters, and adjusting the operation state of equipment in real time through a closed-loop control system. According to the method, through multi-physics field coupling simulation and real-time experimental verification, the quantitative mapping relation among the powder particle size, the cooling rate and the solidification structure is established, and accurate regulation and control of molten drop breaking, cooling and solidification paths in the gas atomization process are achieved.

The invention discloses a method and system for rapidly calculating morphology characteristic parameters of an alloy solidification structure, and relates to the technical field of metal material solidification structure characterization, and the method comprises the following steps: selecting an alloy with any component, obtaining solidification structure samples under different solidification conditions through a plurality of casting experiments, and calculating the morphology characteristic parameters of the alloy solidification structure; measuring the primary dendritic crystal arm spacing of each sample and at least two characteristic parameters representing the overall morphology; establishing a parameter relation graph based on measurement data, and further constructing a multivariate nonlinear fitting model of the primary dendritic crystal arm spacing and each morphological characteristic parameter; and measuring the primary dendritic crystal arm spacing of the target alloy, and substituting the primary dendritic crystal arm spacing into the model to calculate required morphology parameter values. The system comprises a data acquisition module, a model construction module and a parameter calculation module. According to the method, the problem of tedious parameter calculation is solved, the model applicability is wide, rapid evaluation is achieved, and casting process optimization and casting quality control are assisted.

The present invention relates to the technical field of die-casting aluminum alloys, and specifically relates to a design method, a storage medium, and a device for an Al-Si-Mg-Cu heat-treatment-free die-casting aluminum alloy. The method includes establishing a thermodynamic database of the Al-Si-Mg-Cu quaternary system at the Al-rich end; obtaining the solidification microstructure information of the Al-Si-Mg-Cu alloy; training a Gaussian regression model using data with corresponding input features and output features, and completing the training when R<supgt;2< / supgt> is greater than or equal to 0.9; screening out the optimal composition points within the preset alloy composition content range. The storage medium stores computer program instructions; the device includes at least one processor, at least one memory, and computer program instructions stored in the memory; when the computer program instructions are executed by the processor, the method is implemented. The present invention can quickly screen out the optimal composition points within the preset alloy composition content range, and accelerate the design of new high-performance heat-treatment-free die-casting aluminum alloys.

The invention discloses a casting blank structure feature extraction method based on defect tracing, which comprises the following steps: 1) establishing a structure feature extraction and defect prediction system which comprises a steel grade structure case library, a steel grade classification model, a similarity calculation model group and a case library optimization module; 2) inputting component information of steel types, classifying the input steel types through a steel type classification model to determine the types of the input steel types, and finding out the steel types of the same type in a steel type organization case library; and (3) the similarity between the input steel grade and the steel grade of the same type in the steel grade organization case library is calculated through the similarity calculation model group, the most similar steel grade with the similarity larger than a set threshold value is obtained and found out, and the organization characteristics of the most similar steel grade are the input steel grade organization characteristics. According to the method, solidification structure feature extraction based on crack traceability becomes the premise and basis of a subsequent defect prediction model, and the accuracy is predicted through the defect prediction model.

The invention belongs to the technical field of aluminum alloy casting, and particularly relates to a preparation device and method for an aluminum alloy sample with two ends cooled. According to the technical scheme, the preparation device of the aluminum alloy sample with the two ends cooled comprises a cavity, a cavity cover, a sprue plug, a shrinkage compensation plate, a cooling plate and a spraying system, a cavity is formed in the cavity, and the two ends of the cavity are open; the cavity cover is placed on the cavity body and used for covering the mold cavity, the cavity cover is provided with a pouring hole, and the pouring plug is used for blocking the pouring hole; the two shrinkage compensation plates are arranged at the two ends of the cavity respectively, a cooling plate is arranged on the outer side of each shrinkage compensation plate, and two nozzles of the spraying system face the two cooling plates respectively. According to the preparation device and method for the aluminum alloy sample with the two ends cooled, the small-size aluminum alloy solidification structure sample can be prepared, and the structure and segregation characteristics of a large aluminum alloy ingot with the approximate cooling direction from outside to inside are obtained.

The invention provides H2S stress corrosion resistant steel for a petroleum casing pipe and a production method of the H2S stress corrosion resistant steel. The H2S stress corrosion resistant steel comprises the following components: 0.25 to 0.30 percent of C, 0.18 to 0.28 percent of Si, 0.65 to 0.80 percent of Mn, 0.95 to 1.05 percent of Cr, 0.32 to 0.40 percent of Mo, 0.015 to 0.025 percent of Nb, 0.010 to 0.025 percent of Ti, less than or equal to 0.020 percent of P, less than or equal to 0.010 percent of S, 0.26 to 0.32 percent of Ni, 0.20 to 0.36 percent of Cu and the balance of iron and inevitable impurities. Compared with the prior art, chemical components are reasonably designed, and by controlling the continuous casting superheat degree of the large round billet, controlling continuous casting parameters and adjusting the rolling temperature of a steel rolling cogging mill, it is guaranteed that a macrostructure of the steel is free of abnormal and unqualified defects, the segregation control level of components and solidification structures is excellent, the surface state of rolled billets is good, and the quality of finished steel products is improved.

The present application relates to a powder material additive manufacturing method, system and equipment using a cooling medium circulation, the method comprising: slicing and / or partitioning a geometric model of a target component to obtain at least one cooling area including at least a portion of the target component and setting an independent cooling medium control loop for each cooling area; allocating a preset periodic pulse thermal disturbance pattern with a cooling medium flushing frequency and flow rate to at least one cooling area based on at least one cooling area and in combination with real-time temperature distribution and / or process objectives, and applying the pattern to an energy beam scanning process, so that when the energy beam scans the cooling area on a forming base, its corresponding cooling medium control loop is switched to a matching periodic pulse thermal disturbance pattern. By specifically extracting the heat accumulated in the forming base, the cooling rate of the formed part and the molten pool is increased, thereby refining the solidification microstructure and improving the mechanical properties of the formed three-dimensional component.

The present invention provides a method for regulating the directional arrangement of gray cast iron solidification structure by magnetic field, and relates to the technical field of metal material structure regulation. The present invention is based on the magnetocrystalline anisotropy of graphite and ferrite under the action of a magnetic field, and the interaction of magnetic dipoles in ferrite, so as to change the directional solidification structure of gray cast iron. Due to the coupling effect of the magnetocrystalline anisotropy of graphite and the growth characteristics of flake graphite, the application of a magnetic field induces the flake graphite to be regularly arranged parallel to the direction of the magnetic field. Under the action of the magnetic field, the interaction of magnetic dipoles in ferrite and the magnetocrystalline anisotropy of ferrite cause the eutectoid ferrite to change from the randomly distributed equiaxed shape when there is no magnetic field to slender grains arranged parallel to the direction of the magnetic field, and the slender grains parallel to the direction of the magnetic field are arranged parallel to the direction of the magnetic field. <001> The texture components are enhanced. The present invention realizes the regulation of the directional solidification structure of gray cast iron, and solves the problem that other methods cannot realize the directional arrangement of the solidification structure of gray cast iron.

This invention discloses a method and apparatus for applying a composite force field in vacuum arc melting, belonging to the field of high-end alloy special melting technology. The application method includes the following steps: during vacuum arc melting, dynamically adjusting the type and / or intensity of the physical force field applied to the melting area according to different stages of the melting process; applying a first force field combination during the arc initiation and molten pool formation period; applying a second force field combination different from the first force field combination during the stable melting period; and applying a third force field combination different from the second force field combination during the hot capping period. Through the programmed synergistic effect of this composite force field in the arc initiation, melting, and capping stages, the solidification structure of the ingot is significantly improved, segregation is reduced, and density and purity are increased, thereby ensuring the performance and reliability of the alloy under ultra-supercritical extreme environments.

This invention relates to a high-homogeneity bearing steel GCr15 continuous casting billet and its preparation method, belonging to the technical field of bearing steel continuous casting billet preparation. To address the problems of compositional segregation, uneven microstructure, and internal defects in high-end bearing steel continuous casting billets, this invention provides a high-homogeneity bearing steel GCr15 continuous casting billet and its preparation method, including the coordinated control of raw material preparation, converter smelting, refining, and continuous casting. This invention strictly controls the chemical composition of bearing steel from the source, eliminates the risk of raw material segregation at its root, precisely connects the refining-continuous casting temperature, coordinates the time nodes of each process, ensures constant pouring temperature and billet pulling speed, avoids time and temperature discrepancies, effectively improves the solidification structure, and reduces segregation and porosity. By constructing a full-process homogenization control system, the center segregation index of the continuous casting billet is ≤1.05, the center porosity level is ≤1, and the shrinkage cavity level is ≤0.5, significantly improving the uniformity and consistency of the product and meeting the requirements of high-end bearing steel.

The present application provides a method and apparatus, electronic device, and computer-readable storage medium for measuring the permeability of a metal during solidification. The method comprises: obtaining a microstructure image of a metal sample during solidification and a binary image corresponding to the microstructure image; determining a pure liquid phase image of the microstructure image based on the pure liquid phase region indicated by the binary image; determining the solid phase thickness corresponding to each pixel in the solid-liquid mixed region of the microstructure image based on the pure liquid phase image, a preset reference frame, and the property parameters of the metal sample; determining the solid phase fraction and specific surface area of ​​the solidified structure in the microstructure image based on the solid phase thickness and property parameters corresponding to each pixel in the solid-liquid mixed region of the microstructure image; and calculating the permeability of the solidified structure based on the solid phase fraction and specific surface area. This solution enables in-situ measurement of permeability during solidification using a two-dimensional solidification structure image.

The invention provides an aggressive agent for non-destructive testing of an oriented silicon steel solidification structure, a preparation method and a non-destructive testing method. The preparation method comprises the following steps: S1, adding stannous chloride, anhydrous ferric trichloride, anhydrous copper chloride, anhydrous magnesium chloride and sodium dodecyl benzene sulfonate into deionized water, and stirring for dissolving; and S2, sequentially adding absolute ethyl alcohol and hydrochloric acid into the ionized water, and continuously stirring to obtain the aggressive agent. The aggressive agent is developed for oriented silicon steel for a high-voltage transformer, the aggressive agent is expected to be used for carrying out nondestructive characterization on the solidification structure of an oriented silicon steel casting blank, statistical analysis of the microstructure of the casting blank is facilitated, and a technical basis is provided for optimizing a field continuous casting process and regulating and controlling the solidification structure of the casting blank.

This invention discloses a multi-throughput permanent magnet stirring device and method. The device includes a sleeve, a permanent magnet, a permanent magnet rotation mechanism, an A tray, a B tray, a trolley, an annular track, an A telescopic rod, a B telescopic rod, and a control system. The sleeve is nested and assembled with the permanent magnet. The annular track is supported inside the sleeve by the B telescopic rod. The A tray is supported inside the sleeve by the A telescopic rod. The B tray is mounted on the trolley via the tray rotation mechanism. The trolley is slidably assembled with the annular track. Using the permanent magnet stirring device of this application, multiple melts can be stirred simultaneously, enabling diversified and multi-level permanent magnet stirring experiments. It has a simple structure, is easy to operate and maintain, and can be widely used in the field of permanent magnet stirring of metallurgical melts. It can also be used in experimental research, satisfying the needs of diversified laboratory research on the effects of permanent magnet stirring on melt solidification, microstructure, and properties, laying the foundation for future industrial applications.

The invention relates to a powder material additive manufacturing method, system and equipment applying cooling medium circulation, and the method comprises the steps that a geometric model of a target component is subjected to slicing and / or zoning analysis, so that at least one cooling area comprising at least one part of the target component is obtained, and an independent cooling medium control loop is arranged for each cooling area; according to the at least one cooling area and in combination with real-time temperature distribution and / or a process target, a preset periodic pulse thermal disturbance mode with cooling medium scouring frequency and flow velocity is distributed for the at least one cooling area and is applied to an energy beam scanning process; and when the energy beam scans to the cooling area on the forming base station, the corresponding cooling medium control loop is switched to the matched periodic pulse thermal disturbance mode. The heat accumulated by the forming base station is guided out in a targeted mode, the cooling rate of the formed part and the interior of a molten pool is increased, then the solidification microstructure is refined, and the mechanical property of the formed three-dimensional component is improved.

The chemical component of the carbide-based eutectic medium-entropy alloy is CrFeNi (NbC) x, x is larger than or equal to 0.1 and smaller than or equal to 0.3, the carbide-based eutectic medium-entropy alloy is prepared through a vacuum arc melting method, and after vacuum arc melting, the solidification phase of the carbide-based eutectic medium-entropy alloy is FCC, MC carbide and M7C3 carbide; and when x is equal to 0.1, the solidification structure of the alloy is primary FCC + reticular eutectic FCC / MC + superfine eutectic FCC / M7C3. When x is equal to 0.2-0.3, the solidification structure of the alloy is primary MC + primary FCC + reticular eutectic FCC / MC + superfine eutectic FCC / M7C3; the Vickers hardness of the alloy ranges from 235.6 HV to 287.0 HV, the yield strength of the alloy ranges from 439 MPa to 534 MPa, and the compressive strength (Rpc30) of the alloy under the specified strain (30%) ranges from 1482 MPa to 1607 MPa.

This invention discloses a method for synergistic control of residual stress and microstructure in a pulsed current-assisted metal additive manufacturing process, belonging to the field of metal material additive manufacturing technology. The method includes the following steps: S1, setting the process parameters for metal additive manufacturing and planning the area and timing for synchronously applying pulsed current; S2, during the layer-by-layer deposition process of the component, when a high-energy laser beam, electron beam, or electric arc acts on the deposition area to form a molten pool, a pulsed power supply is triggered by a synchronous control unit to apply a pulsed current with preset parameters to the molten pool and the heat-affected zone; S3, through the synergistic effect of the electroplasticity and Joule heating of the pulsed current, thermal stress relaxation, grain refinement, and microstructure homogenization are simultaneously achieved during the manufacturing process. This invention, by employing the above method and precisely controlling the electrical pulse parameters, simultaneously achieves stress relaxation and solidification microstructure optimization during the manufacturing process, significantly improving the dimensional stability, fatigue life, and mechanical properties of the formed component.

The invention discloses a method for preventing silicon cracking of a high-silicon aluminum ingot, which belongs to the technical field of alloy preparation, and can effectively avoid adverse effects of components on a solidification structure by accurately controlling the components of the material, obtain a stable and uniform alloy structure, and fundamentally reduce the risk of silicon cracking caused by component segregation. Besides, most macroscopic inclusions and hydrogen in the melt can be effectively removed through first refining treatment and a specific refining agent A, micron-sized inclusions are further removed, the hot brittleness of the alloy is remarkably reduced, factors inducing silicon cracks are effectively reduced in combination with a second refining treatment process, deterioration is successful in combination with addition of a specific refining agent, and the quality of the alloy is improved. And the morphology of the eutectic silicon is changed from a thick plate sheet shape to a fine fiber shape or a particle shape, so that the harm caused by taking a thick silicon phase as a crack source is fundamentally eliminated, the continuity of an aluminum matrix is enhanced, and the purpose of preventing silicon cracks is achieved.

A method for controlling the solidification structure of high-grade non-oriented silicon steel based on pulse current control, comprising: selecting high-grade silicon steel alloy raw materials and adding rare earth elements; smelting molten steel in an electric arc furnace and monitoring the composition using an online analysis instrument; in the continuous casting process, using an adjustable pulse power supply to optimize the current frequency, amplitude and application time; using a machine learning model to predict defects and automatically adjust the process parameters; slowly discharging the furnace, using an intelligent cooling system to control the cooling speed, reduce thermal stress and reduce the risk of surface defects; then uniform heat treatment is carried out, using layered heating technology to ensure uniform internal structure; then heat the casting blank to hot rolling temperature, and then cold roll the hot rolled plate using gapless rolling technology, and then use nano coating technology for surface treatment. The present application significantly improves the corrosion resistance, wear resistance and oxidation resistance of the cold rolled plate through the nano coating technology, prolonging the service life.

According to the semi-continuous casting process for the copper-magnesium alloy, argon protection smelting is matched with multi-element synergistic alloying, and metal elements and intermediate alloy are added in a staged gradient mode to improve the component uniformity. A vertical pulsed magnetic field synergistic directional solidification technology is introduced, and double-layer protection of a composite covering agent and boron nitride is combined, so that the impurity content is remarkably reduced, and the grain structure is refined. A multi-directional rolling process is matched with a circulating heat treatment method to effectively eliminate residual stress and promote uniform distribution of precipitated phases. And through graded aging stabilization treatment, the precipitated phase form is regulated and controlled, and synergistic improvement of strength and corrosion resistance is achieved. Compared with a traditional process, the alloy obtained through the process has the advantages of being compact in solidification structure, excellent in comprehensive performance, high in yield and the like, and has important application value in the fields of aerospace and rail transit.

The application provides a process for semi-continuous casting of copper-magnesium alloy, which is smelted by argon protection and combined with multi-element synergistic alloying, and metal elements and intermediate alloy are added in stages to improve the uniformity of composition. A vertical pulse magnetic field is introduced to cooperate with the directional solidification technology, combined with a double-layer protection of composite covering agent and boron nitride, which significantly reduces the impurity content and refines the grain structure. The multi-directional rolling process cooperates with the cyclic heat treatment method to effectively eliminate residual stress and promote the uniform distribution of precipitated phase. Through the staged aging stabilization treatment, the morphology of the precipitated phase is adjusted to realize the synergistic improvement of strength and corrosion resistance. Compared with the traditional process, the alloy obtained by the process has the advantages of dense solidification structure, excellent comprehensive performance, high yield, etc., and has important application value in the fields of aerospace and rail transportation.

The application belongs to the field of metal material casting, and discloses a method for improving the hot crack resistance of heat treatment-free aluminum alloy and high hot crack resistance heat treatment-free aluminum alloy. The method comprises the following steps: melting heat treatment-free aluminum alloy to obtain a melt; adding Zr, and optionally Sc and / or Er, to the melt, stirring, degassing, cooling and standing to obtain an alloy melt; carrying out high-temperature melt ultrasonic treatment on the alloy melt to obtain a high-temperature melt, pouring into a mold and carrying out casting to obtain high hot crack resistance heat treatment-free aluminum alloy. The application can effectively control the microstructure and hot crack resistance of the aluminum alloy, and obtain high-quality heat treatment-free aluminum alloy castings with refined solidification structure and eliminated casting hot cracks.

To provide a method for manufacturing stainless steel having strength comparable to that of a nickel-based superalloy, and the stainless steel.SOLUTION: A method for manufacturing stainless steel comprises: cooling a liquid phase containing at least iron, carbon, chromium, and nickel at a cooling rate of 1,000°C / second or more; and forming a eutectic solidified structure by performing eutectic solidification on at least a part of the liquid phase.SELECTED DRAWING: Figure 1

The invention relates to the technical field of metal casting processes, and discloses a high-toughness high-chromium casting process. According to the method, precise regulation and control of a melt microstructure are achieved through composite modification treatment, carbide is distributed in a three-dimensional dispersion mode in combination with a multi-gradient centrifugal casting technology of a five-layer composite module, and the adverse effect of a net-shaped structure on toughness is thoroughly eliminated; the matrix structure and the residual stress field are synergistically optimized through the multi-mode heat treatment and the gradient cryogenic-tempering coupling process, and the interface bonding strength and the impact resistance are remarkably improved; the cross-process parameter transmission system dynamically associates the melt state, the solidification structure and the heat treatment parameters to ensure the process stability and the product homogeneity; the high hardness is maintained, the toughness bottleneck is broken through, the service life of a casting section is prolonged, the high performance and low-cost preparation requirements are considered through technological parameter optimization path design, and the method is suitable for batch production under the heavy load working conditions of mines, cement and the like.

The present invention addresses the problem of providing an iron-based alloy which exhibits high strength even when an expensive alloy element is not added, and can achieve both high ductility and high strength.　This iron-based alloy contains, in mass%, 0.10-0.30% C, 0.1-1.0% Si, 0.2-2.0% Mn, no more than 0.030% P, and no more than 0.030% S, with the remainder comprising Fe and unavoidable impurities, and has a solidified structure in which the arithmetic average particle diameter of the crystals is 10 μm or less.　This iron-based alloy is an alloy for additive manufacturing and contains, in mass%, 0.10-0.30% C, 0.1-1.0% Si, 0.2-2.0% Mn, no more than 0.030% P, and no more than 0.030% S, with the remainder comprising Fe and unavoidable impurities.　This iron-based alloy has the mechanical characteristics of a 0.2% proof stress or a yield point of 700 MPa or more and an elongation of 20% or more.

The invention relates to the technical field of additive manufacturing, in particular to a molten pool solidification interface simulation method for additive manufacturing and a computer program. According to the molten pool area data, carrying out molten pool grid division on a molten pool area; the molten pool grid comprises a grid unit, a cell node, an edge node and a node node; obtaining a cellular score of the grid unit; determining a solid-liquid phase fraction of each node according to the cellular fraction; determining the solid-liquid phase fractions of the cell node and the edge node according to the solid-liquid phase fractions of the node; and determining a solidification interface of the molten pool area according to the solid-liquid phase fractions of the cell node, the edge node and the node node. According to the method, the molten pool solidification interface form in the DED forming process can be simulated under the condition of a large grid size, and the DED forming solidification microstructure can be analyzed and predicted in combination with temperature field data.