478 results about "Nitriding" patented technology

A preparation method for high-nitrogen austenitic stainless steel. The high-nitrogen austenitic stainless steel comprises the following chemical components in percentages by weight: carbon: ≤0.02%; silicon: 0.4-0.8%; manganese: 10.2-12.5%; chromium: 24.5-26.5%; nickel: 13.5-16.5%; molybdenum: 3.2-4.8%; nitrogen: 0.75-0.95%; phosphorus: ≤0.03%; sulfur: ≤0.0025%; vanadium: 0.016-0.022%; niobium: 0.026-0.034%; copper: 0.2-0.35%; aluminum: 0.01-0.02%; cerium: 0.015-0.025%; and the balance of iron and inevitable impurities. The preparation method comprises the steps of raw material charging, vacuum melting, refining, nitrogen-added alloying, deoxidation and desulfurization, casting, electroslag remelting, and secondary casting. The preparation is implemented by using the processes of smelting in a pressurized induction furnace and electroslag remelting under a protective atmosphere; and nitrogen is added by using a method in which a nitrogen alloy and pressurized nitrogen permeation are combined.

The invention provides a steel surface defect online detection method, device and system and a storage medium, and relates to the technical field of defect detection. The method comprises the following steps: acquiring a preset reference spot map; wherein the reference spot map is obtained by establishing a coordinate system for a first aluminum nitride spot image on the surface of a defect-free steel sample under a scanning electron microscope; after the target steel leaves the annealing furnace, generating raised aluminum nitride spots on the surface of the target steel through a pulse nitriding process by utilizing the residual temperature of the target steel; collecting a second aluminum nitride spot image on the surface of the target steel, converting the second aluminum nitride spot image into the coordinate system, and generating an online spot map; and taking the reference spot map as priori knowledge of a pre-trained defect identification model, inputting the online spot map into the defect identification model, and identifying the defect of the target steel. According to the invention, the interference of the steel surface condition and the image quality can be overcome, and the online detection accuracy and efficiency of the steel are improved.

The invention belongs to the technical field of ceramic composite substrate processing, and discloses a high-strength and high-thermal-conductivity aluminum nitride ceramic composite substrate preparation device which comprises a preparation assembly, driving assemblies are arranged on the front side and the rear side of an inner cavity of the preparation assembly correspondingly, a discharging table is arranged on the inner sides of the driving assemblies, and a clamping structure is hinged to the outer side of the discharging table; a feeding mechanism and a discharging mechanism which are located below the discharging table are arranged on the two sides of the preparation assembly correspondingly. Through the arrangement of the connecting rod and the corrugated block, when the driving assembly operates, the whole discharging table is driven to move upwards through the transmission chain, the connecting rod is driven to move to the outer side of the corrugated block, then the corrugated block extrudes the connecting rod and drives the connecting rod to move in a reciprocating mode, and meanwhile the connecting rod drives the movable block to move; and the whole supporting frame is driven to rotate, so that the green body rotates on the inner side of the heating plate, the green body is uniformly sintered, and flaws are avoided.

The application relates to a high-temperature nitriding preparation method of a cobalt-based high-temperature alloy by using nitride dispersion reinforcement, and belongs to the technical field of dispersion reinforcement materials. The cobalt-based high-temperature alloy profile is placed in a high-temperature nitriding furnace, the inner cavity of the nitriding furnace is vacuumized, the cobalt-based high-temperature alloy profile is in a vacuum environment, then argon is filled into the inner cavity of the nitriding furnace, and the temperature is raised to a set temperature of 1100-1200 DEG C; then a mixed gas atmosphere of nitrogen and argon is introduced into the inner cavity of the nitriding furnace, the flow speed is 80-120 mL / min, the cobalt-based high-temperature alloy profile is subjected to nitriding treatment in the furnace for a certain time, and after the high-temperature nitriding process is completed, the temperature is cooled to room temperature at a cooling rate of 20-40 DEG C / min. The method is aimed at cobalt-based high-temperature alloy wire or plate, high-temperature nitriding treatment is carried out in a mixed gas atmosphere of nitrogen and argon, stable nitrides are formed in the alloy organization to play a dispersion reinforcement role, and the problem that the strength of the cobalt-based high-temperature alloy is relatively low can be effectively solved.

This invention proposes a metal soft magnetic powder core with excellent low-frequency magnetic properties and its preparation method, belonging to the field of magnetic materials. Using at least nano-boron powder and iron-silicon soft magnetic alloy powder as raw materials, high-temperature diffusion and high-temperature nitriding treatments are employed. Part of the nano-boron powder forms a high-resistivity iron-silicon-boron permeation layer on the surface of the iron-silicon soft magnetic alloy powder, while some nano-boron powder forms a boron nitride insulating layer with both high resistivity and high thermal stability between the iron-silicon soft magnetic alloy powders, effectively controlling eddy currents. Hot pressing further increases the density of the metal soft magnetic powder core, reduces the demagnetizing field, thereby improving permeability and reducing hysteresis loss. Thus, excellent low-frequency magnetic properties of high density, high permeability, and low loss are simultaneously obtained in the metal soft magnetic powder core.

Method of manufacturing a steel strip comprising the steps of: - casting a molten steel into a slab; - reheating the slab at a temperature of 1150°C or more for a time of 1 hour or more; - hot rolling the steel into a strip, preferably using an average F1 slab entry temperature of more than 1000°C; - coiling the hot rolled steel strip; - batch annealing the steel strip: - at a temperature in the intercritical range (i.e. between Ac1 and Ac3), preferably less than 700°C; - in a non-oxidizing and non-nitrogenizing atmosphere; - for a total annealing time of at least 5 hours, preferably at least 10 hours so as to obtain: a Mn enrichment in austenite such that the Mn content is at least 1.25 times the overall Mn content of the steel; and a C enrichment such that the C content is at least 1.2 times the overall C content of the steel; - cooling the steel after batch annealing in air, forced air or water quenching.

This invention provides an engine valve and a method for manufacturing the same, which can suppress galvanic corrosion even when dissimilar metals are joined, and which exhibits excellent wear resistance and corrosion resistance, for use in engines that use CNG, LPG, or alcohol as fuel. [Solution] The engine valve 10 of the present invention is a joint member in which a shaft portion 14 made of martensitic heat-resistant steel SUH11 and a umbrella portion 12 made of austenitic heat-resistant steel SUH35 are joined. A nitride layer is formed only on the surface of the base material on the shaft portion 14 side from the joint portion 13 between the shaft portion 14 and the umbrella portion 12, leaving the surface of the base material exposed on the umbrella portion 12 side from the joint portion 13.

The invention provides a rare earth iron alloy and a preparation method of nitride thereof, and belongs to the technical field of rare earth magnetic materials. According to the method, a high-purity phase rare earth-iron compound Yb2Fe17 is obtained by combining a briquetting sealing means with a reduction diffusion technology, the high-purity phase rare earth-iron compound Yb2Fe17 is converted into Yb2Fe17N3-delta through a controllable nitriding technology, redundant CaO is removed through water washing, and high-purity Yb2Fe17N3-delta is obtained through drying. The preparation method of the rare earth iron alloy and the nitride thereof, provided by the invention, has the advantages of simple process, low energy consumption, high purity, small crystal grains and the like, and successfully solves the problem that a pure phase is difficult to successfully prepare by means of electric arc melting and the like due to high volatility of Yb. The method provided by the invention is also suitable for preparing volatile alloy materials containing Sm, Mn and the like. The method has remarkable technical advantages in preparation of materials containing volatile alloys.

The invention provides a preparation method of a high-wear-resistance alloy lining plate, and relates to the technical field of wear-resistance alloys, carbon steel and pig iron are mixed, heated and melted, high-carbon ferromanganese, medium-carbon ferrochrome and ferrosilicon are added, heating refining is carried out, aluminum powder is added, the mixture is put into a mold, cooling and demolding are carried out, heating homogenization, quenching and cooling are carried out, and a mother plate is prepared; mixing bismaleimide, the composite powder and sepiolite fibers, heating and stirring, coating a mother board with the mixture, firstly applying negative pressure, then applying positive pressure, heating and cooling to obtain a substrate layer; and placing the mother board in magnetron sputtering equipment, sputtering on the substrate layer to obtain a chromium nitride functional layer, and cooling to obtain the high-wear-resistance alloy lining board. The composite powder is prepared by mixing and heating chromium carbide powder and a hydrogen peroxide solution, filtering, mixing with an ethanol solution and gamma-aminopropyltriethoxysilane, heating, condensing and refluxing, washing and drying, and mixing and heating with amine-terminated polyether and N, N-dimethylformamide. The wear-resistant stability of the alloy lining plate can be improved.

A method for producing a Mo-N based coating structure, comprising providing a substrate (1) to be coated and applying a hard material layer (6) onto the substrate (1), the hard material layer (6) comprising at least one layer (4) of Mo-N having a hexagonal crystal structure and at least one layer (5) of Mo-N having a cubic crystal structure or a mixed hexagonal / cubic crystal structure, the hard material layer (6) being applied by a low-temperature closed-field unbalanced reactive magnetron sputtering coating process.

According to a first aspect of the present invention there is provided a method of coating a bipolar plate, comprising the steps of: providing a bipolar plate wherein at least an outer layer of the bipolar plate comprises metallic titanium; and performing laser nitridation on the bipolar plate so as to form a titanium nitride coating on the outer surface of the bipolar plate. The inventors have found that laser nitridation of a titanium bipolar plate results in a bipolar plate having a high stability TiN coating which has good conformality, chemical stability and / or high conductivity. Furthermore, the formation of the TiN coating by laser nitriding can be well integrated into a manufacturing process of a bipolar plate, such as a roll-to-plate process including a laser welding step, compared to a deposition method known in the prior art, and has the advantages of high efficiency and simplification. The TiN coating on the bipolar plate can be directly used for an electrochemical reactor or can be used as a substrate of a subsequent coating.

The application discloses a hydraulic system for stabilizing pressure of a hot-pressing sintering aluminum nitride heater, which comprises a main oil tank and a stamping oil cylinder; the main oil tank is connected with a first main oil path, the first main oil path is connected with an upper cylinder total oil path and a lower cylinder oil path through a first two-position cartridge valve, the upper cylinder total oil path is connected with an inner cylinder oil path and the main oil tank through a second two-position cartridge valve, and an outer cylinder oil path is connected with the inner cylinder oil path through a cartridge valve; the first main oil path, a second main oil path and a third main oil path are connected with a pressure compensation main oil path; a first hydraulic control check valve is arranged on the inner cylinder oil path and the outer cylinder oil path, the first hydraulic control check valve is connected with a first pressure relief oil path connected with the second main oil path, and the inner cylinder oil path and the outer cylinder oil path are connected with a second pressure relief oil path between the first hydraulic control check valve and the stamping oil cylinder. The design of the inner cylinder and the outer cylinder can realize controllable pressure relief range of the stamping oil cylinder, the pressure relief oil path makes the stability of the pressurizing rate good, and the pressure fluctuation is small during the pressure relief process.

The application discloses an inner gear ring heat treatment conveying and nitriding heat treatment device and heat treatment method, and relates to the technical field of heat treatment. The device comprises a machining table, a supporting assembly, a nitriding furnace cover, a rotary table and an inner support assembly. The machining table is provided with an annular guide rail. The guide rail path is sequentially distributed with a feeding and discharging station, a preheating bin, a nitriding box and a slow cooling box. The supporting assembly is slidably connected with the guide rail and moves along the guide rail. The nitriding furnace cover is arranged corresponding to the supporting assembly and can be buckled to isolate the nitriding atmosphere when descending. The rotary table is arranged on the upper side of the supporting assembly to support the inner gear ring. When passing through the nitriding box, the rotary table drives the inner gear ring to rotate. The inner support assembly is arranged corresponding to the rotary table to realize concentric positioning and radial support of the inner gear ring. The application solves the problems of unstable fixing, inconvenient feeding and discharging and uneven nitriding of the inner gear ring, realizes automatic circulation conveying, improves the degree of automation, production efficiency and overall performance of the inner gear ring.

This invention discloses an L10-type FeNi ordered alloy and its preparation method. The method utilizes a one-step ultrasonic spray thermal decomposition and reduction process to prepare spherical FeNi disordered alloys filled with a pore-forming agent. The pore-forming agent is then removed by alcohol washing to obtain spherical porous FeNi disordered alloys. Following this, high-pressure nitriding and denitrification treatments are performed to finally obtain the L10-type FeNi ordered alloy. This invention offers controllable morphology and size, improving oxidation resistance. The preparation process is simpler, more economical, and has faster nitriding efficiency, facilitating industrialization and promoting the production of high-performance L10-type FeNi ordered alloy magnetic powder.

This invention discloses a method for nitriding and firing silicon nitride-bonded silicon carbide products, comprising the following steps: the product blank is placed in a furnace, preheated at a low temperature, ventilated at a medium temperature, nitrided at a high temperature, cooled at a high temperature, and cooled by air. During low-temperature preheating, the furnace cavity pressure is -100 Pa to 100 Pa; during medium-temperature ventilation, the furnace cavity pressure is 100 Pa to 500 Pa; during high-temperature nitriding and cooling, the furnace cavity pressure is 500 Pa to 1000 Pa; and during air cooling, the furnace cavity pressure is -100 Pa to 100 Pa. In this invention, from low-temperature preheating to air cooling, the pressure inside the furnace cavity remains close to the external atmospheric pressure, resulting in a relatively low-pressure state throughout the firing process. This low-pressure environment reduces the mean free path of gas molecules, which is beneficial for diffusion. The use of dynamic displacement drainage, dynamic nitrogen filling and impurity removal, and air cooling during the firing process greatly enhances the mass transfer process and significantly shortens the nitriding and firing cycle of silicon nitride-bonded silicon carbide products.

The application discloses an aluminum nitride film circuit substrate and a preparation method thereof, and relates to the technical field of aluminum nitride substrates.The application is characterized by the following steps: a titanium film is plated on the surface of an aluminum nitride ceramic substrate by magnetron sputtering, and then a copper film is plated on the surface of the titanium film by magnetron sputtering; and a nickel film is plated on the surface of the copper film by a chemical plating method to prepare the aluminum nitride film circuit substrate.Through the titanium-copper gradient dynamic transition technology, a gradient alloy layer is formed to reduce the interface stress; the titanium and the surface of the aluminum nitride are combined through a chemical bond to form a dense transition layer, thereby relieving the difference in the thermal expansion coefficient; the copper enhances the conductive performance of the surface of the aluminum nitride ceramic substrate; the titanium compensates for the interface defects of the mismatch between the copper and the aluminum nitride ceramic lattice; the chemical nickel plating enhances the hardness and corrosion resistance of the aluminum nitride ceramic substrate, and the aluminum nitride film substrate is endowed with weldability and bondability.

The invention discloses a heat treatment method for improving matching of strength, plasticity and toughness of a Ti55531 alloy, which is specifically characterized in that the whole heat treatment is carried out under the protection of argon, so that the titanium alloy is effectively prevented from absorbing hydrogen and even nitriding at a high temperature, serious reduction of local performance is avoided, and the heat treatment method is suitable for heat treatment of titanium alloy bars, forging stocks and complex workpieces; and a two-section annealing process of first rapid cooling and then slow cooling is adopted, a fine lamellar layer is formed through rapid cooling to improve the strength, then slow cooling is performed to weave a part of thicker lamellar structures from a fine needle-shaped secondary alpha phase to improve the toughness of the material, so that strength and toughness matching is realized, a lamellar alpha-phase structure with an ideal thickness is formed more accurately, and the strength of the material is improved. And the challenging matching requirements of strength, plasticity and toughness can be met.

The application discloses a preparation method of sheet-shaped aluminum nitride ceramic powder and a product thereof. In the application, deionized water is used as a dispersion medium, Al2O3 powder, carbon black and Na3AlF6 are uniformly mixed through ball milling, and a precursor is obtained through drying; and the precursor is subjected to a carbon thermal reduction reaction and a nitriding reaction in a flowing nitrogen atmosphere to obtain micron-grade sheet-shaped aluminum nitride ceramic powder. The application can directly generate sheet-shaped AlN without pre-preparing a sheet-shaped template, and solves the technical defects of existing processes which depend on the morphology of a precursor.

The application relates to a three-section connecting rod joint surface ion nitriding device, which comprises a nitriding assembly, an assembling assembly and a rotary driving assembly. The rotary driving assembly is used for contactless driving rotation of a rotary seat, and is used as a contactless driving source through the suction and release of an electromagnet. The nitriding assembly inside the connecting rod can rotate through a transmission structure. The ion nitriding device is provided with a rotary base, so that the middle section of the connecting rod can rotate in a furnace cover. The problem of temperature non-uniformity and non-uniform nitriding caused by the distance difference between the cathode and the anode is reduced. The electromagnet drives the screw cylinder to reciprocate up and down on the basis of not damaging the sealing property of the furnace cover. The screw cylinder drives the driving rod to reciprocate, and the one-way driving structure drives the gear disc to rotate. The device is completely and continuously driven in a sealed and high-temperature environment.

The invention provides a metal monatomic loaded lamellar stacked carbon nitride hollow cubic material as well as a preparation method and application thereof, and ACT-Fe / Na-C3N4 (0.04) with a three-dimensional hollow cubic morphology and uniformly dispersed in-plane / interlayer double Fe monatomic sites is successfully prepared by utilizing a morphology amorphous-to-crystalline transition (ACT) strategy. And crystal form regulation and fine design of metal atom sites are integrated. The built in-plane Fe-N4 and interlayer Fe-N5 coordination structure significantly improves the electron transport efficiency of the material, enhances the adsorption and activation ability to O2 molecules, realizes efficient generation of. O2 <->, and provides controllable reaction conditions for selective conversion of biomass, so that the HMF conversion rate reaches 98.8%, and the HMFCA selectivity reaches 83.7%. In addition, the ACT strategy is generally suitable for the assembly of a variety of transition metals (Mn, Fe, Co, Cu or Cd) at the same time.

The utility model discloses a pulsed power supply integrated glow ion nitriding furnace, which relates to the technical field of metal material surface treatment and comprises a furnace body structure, the furnace body structure comprises a nitriding furnace, two sides of the nitriding furnace are communicated with nitrogen ports, a furnace body of the nitriding furnace is provided with a sensor interface, and the bottom end of the nitriding furnace is integrated with an integrated power supply module. A support is supported at the bottom end of the integrated power supply module, a mounting seat is fixedly arranged in a furnace body of the nitriding furnace, a temperature control layer is arranged between an inner layer and an outer layer of the nitriding furnace, the temperature control layer is communicated with a temperature control structure, a compression structure is arranged on the temperature control structure, and the compression structure is connected with a valve structure. The nitriding furnace is matched with a dynamic temperature control layer driven by compression, so that the process temperature change response time is remarkably shortened, and the temperature uniformity and the process controllability are ensured; the operation safety of the equipment is effectively guaranteed through a sealing system and an intelligent valve group, and the problems that traditional equipment is lagged in temperature control, too high in energy consumption, insufficient in process stability and the like are integrally solved.

The invention belongs to the technical field of synthesis and preparation of aluminum nitride, and discloses a controllable and extensible preparation method of a one-dimensional aluminum nitride nanowire / nanotube, which comprises the following steps: (1) uniformly mixing a solid aluminum source and a solid nitrogen source, transferring the mixture into a rotatable crucible, transferring the crucible into a tubular furnace, sealing the tubular furnace, and carrying out heat preservation for 2-3 hours; vacuumizing and then introducing protective gas; (2) under the condition that protective gas is continuously introduced, the tubular furnace is heated to a preset target temperature for a nitridation reaction, and the nitridation reaction is carried out under the condition that a crucible rotates at a constant rotating speed; and after the reaction is finished, cooling the tubular furnace and stopping the rotation of the crucible to obtain a one-dimensional aluminum nitride nanowire or nanotube product. According to the method, the solid aluminum source and the solid nitrogen source are used as raw materials, and the crucible rotation is introduced during the nitridation reaction to carry out dynamic enabling improvement, so that the single-crystal aluminum nitride nanowire or nanotube with high purity and uniform morphology can be efficiently synthesized.

The present application provides a kind of method for producing vanadium-nitrogen alloy by replacing part of sheet vanadium with powder vanadium and vanadium-nitrogen alloy, the method comprises: replacing part of sheet vanadium with powder vanadium to be matched into vanadium-nitrogen alloy production line to carry out mixing, balling and nitriding reduction reaction in turn, to obtain vanadium-nitrogen alloy;Wherein, the proportion of powder vanadium replacing part of sheet vanadium is 8-12wt%.The present application produces vanadium-nitrogen alloy by replacing part of sheet vanadium with powder vanadium, which avoids the high purity required by using all sheet vanadium, and also avoids the fine particle size and high energy consumption required by using all powder vanadium.By reasonably limiting the matching ratio between powder vanadium and sheet vanadium, the purity requirement of raw materials is reduced, and the early grinding period is shortened, thereby saving energy consumption and cost, which is conducive to large-scale popularization and application.

A method for operating a vertical furnace having a reaction chamber for depositing a molybdenum nitride layer on a plurality of wafers is disclosed. The method includes a molybdenum nitride (MoN) depositing run for depositing the MoN layer; and a cleaning run for cleaning the reaction chamber. The MoN deposition run comprises providing a plurality of wafers in a wafer boat and loading the wafer boat in a substantial vertical direction into the reaction chamber; heating the wall of the reaction chamber; flowing a molybdenum precursor into the reaction chamber; flowing a nitrogen precursor into the reaction chamber to deposit MoN on the wafers in the wafer boat; and removing the plurality of wafers in the wafer boat from the reaction chamber. The cleaning run comprises flowing a cleaning to remove deposited layers in the reaction chamber and the cleaning run is ran every 1 to 10 deposition runs.

The invention discloses a low-expansion three-temperature cold and hot plate and a preparation method, and belongs to the field of precise alloy components. The cold and hot plate is made of titanium-niobium-based alloy, the titanium-niobium-based alloy comprises, by atomic percent, 25%-35% of Nb, the total content of V and / or Ta smaller than or equal to 3% and the balance Ti, the titanium-niobium-based alloy comprises a three-temperature structure of a low-temperature adaptation area, a normal-temperature stable area and a high-temperature tolerance area, the thickness of the titanium-niobium-based alloy ranges from 1.5 mm to 2 mm, and the surface of the titanium-niobium-based alloy is provided with a nitride layer or a passive film. The preparation method comprises the steps of burdening, 2-3 times of vacuum consumable smelting, hot forging, hot rolling, partition cutting, pre-deformation regulation and control, solid solution quenching, cold rolling finishing, splicing forming and the like, and vacuum stress relief annealing and dual performance detection are matched. The method is suitable for scenes such as chip packaging and precision detection, and is low in cost and high in qualified rate.

The invention relates to the technical field of ceramic-based composite materials, in particular to an aluminum nitride ceramic homogeneous joint combining screen printing with liquid phase sintering and a preparation method of the aluminum nitride ceramic homogeneous joint. The preparation method comprises the following steps: uniformly mixing nano powder of aluminum nitride, a sintering aid I and a sintering aid II to obtain mixed powder I, and dispersing ball-milled and dried mixed powder II to obtain the solder; sequentially polishing, cleaning and drying the welding surface of the aluminum nitride ceramic wafer to obtain a welding surface I and a welding surface II; coating a welding flux on the welding surface I on which the silk screen plate surface is placed, taking down the silk screen plate surface, and drying to obtain a welding surface I'coated with the welding flux; and covering the welding surface I'with the welding surface II, and sequentially carrying out first-stage, second-stage and third-stage forming sintering to obtain the aluminum nitride ceramic homogeneous joint. According to the method, the AlN / AlN ceramic homogeneous joint is prepared through a liquid phase sintering method for the first time, residual stress basically does not exist in the joint, the thickness consistency of the middle layer is accurately controlled through the screen printing technology, and the shearing performance and the thermal shock resistance of the homogeneous joint are improved.

Provided herein is a use of an aqueous slurry or powder composition, a method for marking an object made of a steel, metal or non-ferrous metal alloy, the method comprising the step of applying a powder or aqueous slurry to the object to provide a mark, and a marked object obtained thereby, the powder or aqueous slurry comprises: A, an aluminum compound other than aluminum titanate and aluminum nitride, preferably comprising one or more selected from the group consisting of aluminum oxide and aluminum hydroxide; and B is one or more particles selected from the group consisting of oxides, hydroxides, carbides, nitrides, aluminates and titanates of aluminum titanate, aluminum nitride, and metals or semimetals other than aluminum. The marking can be provided on an object made of, for example, steel or other metal or metal alloy, is durable even at high temperatures, but can be removed by a simple physical operation, for example, scrubbing or wiping, without compromising the nature or size of the marked object.

This invention relates to the field of gray cast iron material preparation technology, and particularly to a method for preparing multi-alloy synergistically strengthened gray cast iron, comprising: adding steel raw materials to a smelting apparatus and heating to form molten iron; adding a chromium alloy to the molten iron, heating and holding at that temperature to form a basic mixture; determining the degree of furnace lining peeling based on the vibration frequency of the smelting apparatus, and determining the overheating risk level of the basic mixture based on the degree of furnace lining peeling; determining a target heating temperature based on the overheating risk level; determining the eddy current risk level based on the actual rotation speed; adjusting the stirring intensity during the smelting process based on the eddy current risk level; detecting the mixing ratio of the basic mixture and adjusting the amount of steel raw materials or the chromium alloy added to form a target solution; and simultaneously adding manganese nitride, alloyed tin, and ferrous sulfide to the target solution in a specified ratio to form multi-alloy synergistically strengthened gray cast iron. This invention improves the strength, toughness, fluidity, and resistance to solidification defects of gray cast iron.