694 results about "Ductile iron" patented technology

A cast image enhancement method for metallographic analysis is disclosed. According to the method, a casting metallographic image is collected, analysis and feature recognition of the casting metallographic image are carried out at the rear end through an image processing and analysis algorithm based on artificial intelligence and deep learning, and therefore multi-dimensional representation features related to a casting metallographic phase are captured from the casting metallographic image, and enhancement processing of the casting metallographic image is carried out. In this way, analysis and control over the nodular cast iron inoculation process can be conducted more finely in the follow-up process, and reliable support is provided for production quality control over materials such as nodular cast iron.

The invention relates to the technical field of elbow polishing, and discloses a spheroidal graphite cast elbow casting polishing device which comprises a polishing table, a supporting table and a pair of placing tables are arranged at the top of the polishing table, a bent section of an elbow is placed above the supporting table, a straight section of the elbow is placed above the two placing tables, and motors are arranged on one sides of two ports of the elbow. Output shafts of the motors are fixedly connected with connecting rods, the outer walls of the connecting rods are fixedly connected with a first polishing cutter and a second polishing cutter, the diameter of the first polishing cutter is the same as the outer diameter length of the bent pipe, the diameter of the second polishing cutter is the same as the inner diameter length of the bent pipe, and an adjusting assembly used for driving the two containing tables to conduct position adjustment is arranged below the containing tables. And a chipping removing assembly for treating chippings on the inner wall of the pipeline is arranged on the side, away from the motor, of the second polishing knife, the chippings generated by polishing of the inner wall of the pipeline can be removed in time through the chipping removing assembly, and the situation that the chippings cause unsmooth or blocking of the pipeline, and consequently follow-up use of the bent pipe is affected is avoided.

The invention discloses a laser cladding preparation method for improving the wear resistance of a cladding layer by doping tungsten carbide. According to the method, cladding process parameters are preliminarily obtained based on finite element heat flow analogue simulation, cladding layer preparation is carried out, cladding quality characterization is carried out to obtain the optimal cladding process parameters, and finally the cladding layer with the wear-resistant characteristic is obtained. The method comprises the following steps: firstly, constructing a heat flow coupling three-dimensional model, carrying out grid division, establishing a heat source model, defining thermophysical parameters of tungsten carbide (10-15%) nickel alloy composite powder and a matrix, and determining simulated boundary conditions; setting a multi-factor process parameter combination to carry out numerical simulation calculation, and determining laser processing process parameters of laser power, scanning speed and light spot diameter; preparing a cladding layer on the surface of the nodular cast iron by using tungsten carbide (10-15%) nickel alloy composite powder through a laser cladding method; and carrying out microscopic morphology and microhardness experiments to carry out quality analysis verification on the cladding layer, determining the optimal process parameters of laser power, scanning speed and light spot diameter when the cladding layer has no obvious defect morphology and the hardness is higher than that of the raw material, and obtaining the laser cladding preparation method for improving the wear resistance of the cladding layer by doping tungsten carbide. The invention provides a new research method and a high-quality preparation approach for improving the wear resistance of the cladding layer by tungsten carbide, and can be widely applied to the fields of strengthening and repairing mining machinery, aerospace parts and the like.

The invention relates to the technical field of intelligent manufacturing, in particular to a nodular cast iron alloy component self-adaptive optimization method and system based on artificial intelligence, and the method comprises the following steps: obtaining furnace temperature and component parameters, generating a stable comparison legend, screening offset abnormal combinations to form an available set, extracting performance curve characteristics to construct a trend chart, and obtaining a nodular cast iron alloy component self-adaptive optimization result. And superposing the structural parameters and the element distribution positioning segregation area, and outputting feeding correction parameters to generate an optimization scheme. According to the method, normalization processing is carried out on furnace temperature, carbon-silicon ratio and other multi-factor offset values, a component offset map is constructed, trend feature extraction and sorting of response curves under multiple working conditions are combined, component combinations with stable performance are screened out, a mapping relation is established through the structural curvature, the wall thickness slope and the injection rate, and a spatial coincidence map is generated through coincidence analysis. And the feeding direction and the injection rate are inversely calculated, dynamic adaptation of components and the structure is achieved, and the structure uniformity and the performance consistency are improved.

The invention discloses a high-performance heterogeneously-welded special-shaped combustion chamber piston and a preparation method thereof, a special-basin-shaped combustion chamber and an oil duct structure are directly formed through a rolling process, and heterogeneously-connected between a head part and a skirt part of the piston is realized in combination with a nitrogen protection friction welding technology. The piston head is made of low-silicon high-chromium ferrite-based alloy, the skirt is made of quenched and tempered steel, non-quenched and tempered steel or nodular cast iron, and the welding face is designed to be in a wave shape so as to enhance the bonding strength. The preparation process comprises vacuum smelting, multi-pass rolling, precise welding and surface treatment, the combustion efficiency, the lightweight level and the reliability of the piston are remarkably improved, and the piston is suitable for high-load working conditions such as diesel engines and natural gas engines.

The invention discloses a sand mold casting forming device for nodular cast iron production, and relates to the technical field of nodular cast iron production, the sand mold casting forming device comprises a base, a first mounting groove is formed in the top of the base, and four supporting rods are fixedly mounted at the positions, located on the two sides of the first mounting groove, of the top of the base; a top plate is arranged among the tops of the four supporting rods, a hydraulic cylinder is fixedly mounted at the top of the top plate, the output end of the hydraulic cylinder penetrates through the top plate and is connected with a lifting plate, a displacement mechanism is arranged in the first mounting groove, and a clamping mechanism is arranged outside the displacement mechanism. Through lead screw transmission and motor driving of the displacement mechanism, automatic transfer of a sand mold is achieved, the clamping mechanism automatically drives a clamping plate to clamp the sand mold in the transfer process through cooperation of a guide plate and a first rolling wheel, a first spring provides buffering clamping force, the stability during pouring is guaranteed, the situation that the mold is damaged due to excessive clamping is avoided, and the production efficiency is improved. Clamping is automatically relieved during resetting, and operation is convenient.

The invention provides a nodular cast iron material and a preparation method and application thereof. The preparation method of the nodular cast iron material comprises the following steps that S1, a mixture of pig iron, low-manganese waste steel and foundry returns is heated to be completely molten, alloy and auxiliary materials are supplemented and adjusted to target components, and base iron is obtained; s2, a spheroidizing agent is added into the base iron to conduct spheroidizing treatment, ladle-to-ladle inoculation is conducted after spheroidizing treatment, and an efficient inoculant is added during ladle-to-ladle inoculation; s3, pouring is conducted, and during pouring, a long-acting stream inoculant is added for instantaneous inoculation; and S4, carrying out vibration aging treatment to obtain the nodular cast iron material. According to the nodular cast iron material, collaborative upgrading is achieved in the three dimensions of graphite form-matrix strength-thermal stress dissipation, in a bench test, the number of hot cracks is greatly increased, the service life is obviously prolonged, and reliable guarantee is provided for braking safety of heavy vehicles.

The invention provides a method for on-line detection of spheroidization rate and shrinkage porosity index of nodular cast iron, which comprises the following steps: pouring molten iron subjected to spheroidization into a thermal analysis sample cup, recording the change rule of the temperature of the molten iron in the thermal analysis sample cup along with time, and drawing a cooling curve of solidification time-temperature; according to the shape of the cooling curve, determining which of a hypoeutectic solidification mode, a near-eutectic solidification mode and a hypereutectic solidification mode the solidification mode of the spheroidized iron liquid belongs to; different calculation formulas are adopted for predicting the nodularization rate and the shrinkage porosity index of the nodular cast iron according to the three different solidification modes. The method comprises the following steps: drawing a cooling curve between solidification time and temperature of molten iron, carrying out numerical differential treatment on the curve to obtain a temperature value of a feature point, and judging which solidification mode of the molten iron belongs to a hypoeutectic solidification mode, a near-eutectic solidification mode and a hypereutectic solidification mode according to the shape of the cooling curve. And further calculating the spheroidization rate and shrinkage index of the spheroidized molten iron through a formula.

The invention relates to a nodular cast iron pipe machining cutting device, and relates to the technical field of cast iron pipe production and machining, the nodular cast iron pipe machining cutting device comprises a base, a cutting mechanism for cutting a pipe fitting and a clamping mechanism for fixing and clamping the pipe fitting; the vertical plates are arranged left and right, supporting assemblies for supporting the inner walls of the pipe fittings are fixed to the sides, close to the cutting mechanism, of the vertical plates, and the two supporting assemblies are arranged in a mirror image mode. The supporting assembly comprises a supporting rod and an air bag I; the supporting rods are of telescopic adjusting structures and are fixed to the corresponding vertical plates. The first air bag is of an annular structure and connected to the outer side of the telescopic end of the supporting rod in a sleeving mode, and the inner wall of the pipe fitting is supported through inflation expansion. The technical effects that the interior of the pipe fitting is stably supported during cutting, the quality of a cut pipe opening is improved, the stability during cutting is improved, and the cutting efficiency is improved can be achieved.

The invention belongs to the technical field of polishing devices, and particularly relates to a spherical polishing device for spheroidal graphite casting production, which comprises a workbench, one side of the upper end surface of the workbench is slidably connected with a rack I, the middle part of the upper end of the rack I is rotatably provided with a rotating plate, and the lower end of the rotating plate is fixedly connected with a fixed disc; a sliding groove is formed in the fixing disc in the radial direction, a radial rod is slidably connected to the sliding groove, a polishing brush is fixedly connected to the lower end of the radial rod, and a base is fixedly connected to the middle of the upper end face of the workbench. By means of the rolling type feeding mechanism, a plurality of disorderly stacked spheroidal graphite castings can be longitudinally arranged, then sequentially arranged on the supporting column in a sleeving mode and fixed, automatic feeding of the multiple to-be-polished spheroidal graphite castings is achieved, and the situation that the multiple to-be-polished spheroidal graphite castings are stacked together in a disordered mode is avoided; and clamping structures such as manipulators are difficult to clamp and fix one by one, so that the subsequent polishing work of the spheroidal graphite castings is influenced.

The invention relates to the technical field of quenching treatment, in particular to a nodular cast iron isothermal quenching cooling method and an isothermal quenching cooling device.The method comprises the steps that when nodular cast iron of the current batch is subjected to cooling treatment in a cooling stage before isothermal quenching in a salt bath furnace, a thermal image of the surface of the salt bath furnace is collected in real time; acquiring a first characteristic value of each nodular cast iron; obtaining a furnace wall area and a non-furnace wall area in each thermal image; obtaining an average temperature value of each non-furnace-wall area; acquiring a local high-temperature area in each thermal image; acquiring a high-temperature characteristic value of each thermal image; acquiring a second characteristic value of each nodular cast iron; and the optimal rotating speed of the stirring device is obtained when the next nodular cast iron of the nodular cast iron of the current batch is subjected to cooling treatment in the cooling stage before isothermal quenching. The invention aims to improve the isothermal quenching cooling quality of the nodular cast iron by adjusting the rotating speed of the stirring device during the isothermal quenching cooling of the nodular cast iron.

The invention discloses nodular cast iron and a production process, and relates to the technical field of nodular cast iron preparation. The invention discloses a nodular cast iron production process. Carbon steel scrap and recirculated iron are used as main furnace materials for smelting, a spheroidizing agent and a first nucleating agent are added for a spheroidizing reaction, pouring is conducted, stream secondary inoculation is conducted, solidification cooling and heat treatment are conducted, and a casting is formed. The process route of the nodular cast iron production process is different from that of a foreign high-silicon solid solution strengthening process route for improving the elongation rate, pig iron is not adopted, only waste steel and recirculated iron are used as main raw materials, and the prepared nodular cast iron meets the requirements of casting products for high strength and high elongation rate of nodular cast iron at the same time; and no precious alloy is added in the production process, so that the production cost is greatly reduced, and the economic benefit is remarkably improved.

The invention relates to the field of marine pipeline engineering, in particular to a nodular cast iron jacking pipe for internal action type integral trenchless pipeline construction, which comprises a nodular cast iron jacking pipe and a control end, and is characterized in that a birdmouth and an inserting end are integrally formed on two sides of the nodular cast iron jacking pipe; a first pressure sensing end and a second pressure sensing end are arranged on the inner wall of the birdmouth, a sliding material discharging opening is formed in the top of the nodular cast iron jacking pipe and the surface of the nodular cast iron jacking pipe, and a metal mounting strip is mounted on the outer surface of the nodular cast iron jacking pipe in an embedded mode; and a third pressure sensing end and a fourth pressure sensing end are arranged at the two ends of the surface of the metal mounting strip. By monitoring the pressure change of the outer wall of the pipeline and the seepage state of the sliding material in real time, the injection amount of the sliding material is dynamically regulated and controlled to adapt to seawater pressure fluctuation and seabed geological change; and meanwhile, the pipeline breaking risk is calculated through multi-dimensional stress analysis, a construction middle layer is accurately set, and the problem of pipeline continuous laying in the deep sea environment is solved.

The invention relates to the technical field of water conservancy projects, and discloses a two-way water stop cast iron gate with a protection function, comprising: a door-shaped gate frame, which is internally provided with a vertical lifting area; the nodular cast iron gate is movably mounted in the vertical lifting area; the bidirectional self-adaptive sealing system comprises an adjusting cavity which is arranged in the nodular cast iron gate and is through up and down; the connecting rod is fixed to the top of the door-shaped gate frame and extends into the adjusting cavity. The piston assembly can move in the adjusting cavity; when the gate descends, water flow penetrates through the filtering structure to enter the adjusting cavity, the self-weight of the gate is increased, the sealing effect is assisted, the gate can still be kept in a closed state especially under the low-water-pressure or water-free working condition, when the gate ascends, water in the adjusting cavity reversely scours the composite filtering plate, impurities are taken away, and self-cleaning of the filtering system and the bottom sealing strip is achieved; the manual maintenance frequency is reduced, and the device has the advantages of being high in practicability and self-cleaning.

The invention discloses a nodular cast iron casting casting device, and relates to the technical field of casting, the casting casting device comprises a centrifugal casting mechanism, the centrifugal casting mechanism comprises a mold cylinder and a centrifugal driving assembly, the output end of the centrifugal driving assembly is in transmission connection with the mold cylinder, and the centrifugal driving assembly is used for driving the horizontally arranged mold cylinder to rotate; the material uniformizing mechanism comprises a material uniformizing barrel and a material uniformizing driving assembly, the output end of the material uniformizing driving assembly is in transmission connection with the material uniformizing barrel, the material uniformizing driving assembly is used for driving the material uniformizing barrel to rotate, a plurality of material uniformizing holes are formed in the barrel wall of the material uniformizing barrel, and in the liquid injection state, the material uniformizing barrel is located in the mold barrel and is coaxially arranged with the mold barrel; the rotating direction of the material uniformizing barrel is the same as that of the mold barrel, and the rotating speed of the material uniformizing barrel is higher than that of the mold barrel; the liquid injection mechanism is arranged in the material uniformizing barrel, and the liquid injection mechanism is used for conveying the molten liquid into the material uniformizing barrel; according to the casting device, the metal liquid can be uniformly sprayed, and the wall thickness deviation is reduced.

The invention relates to the technical field of casting of iron castings, in particular to a casting method of a nodular iron casting, which comprises a workbench, a lower die holder is arranged at the top of the workbench, an upper die holder matched with the lower die holder is arranged above the lower die holder, and an air cylinder for pushing the upper die holder to move is arranged at the top of the upper die holder; and the operating mechanism comprises an electric sliding rail frame, the electric sliding rail frame is fixedly connected to the top of the workbench, and an electric sliding block capable of sliding left and right on the outer side of the electric sliding rail frame is arranged on the outer side of the electric sliding rail frame. Before a nodular iron casting is poured, dust and impurities in the inner wall of the upper mold base and the inner wall of the lower mold base can be cleaned at the same time, cleanliness in the mold is guaranteed, a release agent can be evenly sprayed into the mold through the cleaning assembly, the release agent can form a layer of film on the surface of the mold, and the mold is prevented from being damaged. And the product is prevented from being adhered to the mold in the forming process, so that the product can be smoothly demolded.

This invention relates to a vermicular cast iron alloy with high mechanical strength and thermal conductivity requirements to replace the conventional gray and vermicular cast irons and introduces a manufacturing process for high mechanical strength and thermal conductivity vermicular cast iron alloy and internal combustion engine parts produced from said alloy. The alloy includes carbon, manganese, tin, copper, molybdenum, silicon, magnesium, rare earths, chromium, titanium, niobium, vanadium, tungsten, phosphorus, sulfur, aluminum, and nickel. The alloy has a graphite microstructure consisting of up to 70% of vermicular particles and up to 30% of nodular particles in area, with a matrix in area up to 80% pearlitic and up to 20% ferritic, with presence of segregating carbides of up to 1%.

The invention provides a nodular cast iron water grate casting mold with a cooling system and a casting method, and relates to the technical field of mold casting machining. The nodular cast iron water grate casting mold with the cooling system comprises a base, a guide frame is fixed to the base, a top base is fixed to the guide frame, a hydraulic cylinder is fixed to the top base, a hydraulic rod is fixed to the hydraulic cylinder, an upper mold base is fixed to the hydraulic rod, an upper ring is fixed to the outer portion of the upper mold base, and an upper ejector rod is fixed to the upper mold base. A lower die holder is fixed on the base, a lower ring is fixed outside the lower die holder, a lower ejector rod is fixed on the lower die holder, a liquid cooling structure is arranged on the top holder, an outer support is fixed outside the base, sealing structures are arranged on the upper die holder and the lower die holder, and an air cooling structure is arranged on the outer support. According to the nodular cast iron water grate casting mold with the cooling system and the casting method, the upper mold base and the lower mold base can be sealed through the sealing structure, the mold can be cooled through the liquid cooling structure, a casting can be cooled through the air cooling structure, and the casting cooling effect is improved.

The mold comprises a lower box shell, a middle box shell, an upper box shell and a reinforcing top cover, the middle box shell is connected with the lower box shell, the upper box shell is assembled at the upper end of the middle box shell, the reinforcing top cover is assembled at the upper end of the upper box shell, and the reinforcing top cover is connected with the middle box shell. A machining groove is formed in the top of the reinforcing top cover, the left side and the right side of the machining groove communicate with a sand-coated pouring cup and an exhaust channel correspondingly, the exhaust end of the exhaust channel communicates with waste gas purification equipment, waste gas generated in the casting process is guided into the waste gas purification equipment through the exhaust channel, and the waste gas can be filtered and purified. According to the mold for casting the ductile iron support and the casting process, natural discharge of gas in the pouring process is promoted, and the situation that the quality of a casting is affected by gas retention is avoided; the chemical components of the casting are controlled, and the pouring temperature is combined, so that the uniformity and mechanical property of the ductile iron structure are ensured, and the comprehensive quality of the casting is improved.

The present invention discloses a method for evaluating and regulating the wear resistance of ductile iron based on the electronic work function, which relates to the technical fields of surface engineering and performance evaluation. The method includes collecting the electronic work function data and material characteristic data on the surface of ductile iron; extracting the characteristics of the electronic work function data to obtain the electronic work function characteristics; establishing a mathematical model based on the electronic work function characteristics to analyze the correlation between the electronic work function data and the material characteristic data; analyzing the relationship between the electronic work function characteristics and the wear resistance, and establishing a comprehensive evaluation model to evaluate the wear resistance of ductile iron. The present invention combines characterization techniques, complex data analysis methods and multivariate statistical models at the same time. It can not only deeply understand the connection between the electronic structure and macroscopic properties of materials, but also establish a comprehensive evaluation model to predict the wear resistance of ductile iron; this method guides the design of materials and the optimization of the production process.

The invention relates to the technical field of nodular cast iron and an annealing method thereof, and discloses an annealing method for improving elastic modulus and strength of nodular cast iron and application, the annealing method comprises the following steps: first-stage annealing and high-temperature decomposition: heating to 880-980 DEG C along with a furnace, and preserving heat for 15-36 hours; second-stage annealing and low-temperature graphitization: cooling to 650-860 DEG C, preserving heat for 3-5 hours, and then quickly discharging from the furnace for air cooling; and performing surface treatment: performing shot blasting to remove oxide skin to obtain the nodular cast iron material. According to the scheme, the nodular cast iron material is prepared from the following raw materials in percentage by mass: 1.8 to 2.3 percent of C, 1.3 to 2.2 percent of Si, 0.3 to 0.7 percent of Mn, 0.002 to 0.005 percent of Bi, 0.002 to 0.01 percent of Sb, less than 0.06 percent of P, less than 0.2 percent of S and the balance of Fe. Compared with the prior art that two-stage annealing (such as furnace cooling to 595-635 DEG C after 900-950 DEG C treatment and heat preservation) needs to be matched with special components such as high rare earth and high phosphorus, the steps are complex and the cost is high, the phosphorus content and the rare earth content of the material in the scheme are low, the elastic modulus and the tensile strength of the nodular cast iron can be effectively improved by adding a proper amount of nodulizing agent, the production process is simplified, and the production cost is reduced. And the cost can be reduced.

The invention relates to the technical field of casting mold cooling capacity regulation and control and material-process collaborative optimization, in particular to a V-method precise resin sand mold casting process method suitable for gray iron or ductile iron. The invention relates to a V-method precise resin sand mold casting process suitable for gray iron or ductile iron, which comprises the following steps: firstly, preparing gradient function modified resin sand, mixing spherical reclaimed sand with various materials such as novolac epoxy resin, and carrying out multi-step stirring and surface modification treatment; an intelligent temperature control sand box is prepared, and then the steps of forming negative pressure curing, composite inoculation treatment, vacuum differential pressure pouring, intelligent cooling control and the like are carried out; in the process, special materials and structures such as a core-shell curing agent, a double-layer film and a core-spun yarn are used, and precise process control is achieved. According to the process, through material innovation and process optimization, the sand mold strength and stability are improved, and casting defects are reduced; the casting quality is improved through the precise temperature control and pouring mode, and the mechanical property is enhanced through composite inoculation; the method is environment-friendly and economical, reduces the cost, improves the yield and has a wide application prospect.

The invention discloses nodular cast iron and a heat treatment method and application, and belongs to the technical field of nodular cast iron. The nodular cast iron is prepared from, by mass, 3.4%-3.8% of C, 2.0%-3.0% of Si, smaller than or equal to 0.6% of Mn, 0.03%-0.06% of Mg, smaller than or equal to 0.15% of Mo, larger than or equal to 0.2% and smaller than or equal to 1% of Cu and Ni, smaller than or equal to 0.02% of rare earth Re and the balance Fe and inevitable impurities. The nodular cast iron is high in pearlite content and smaller in lamellar spacing, the fatigue strength, the tensile strength and the yield strength can be remarkably improved, meanwhile, the nodular cast iron has the advantage of being low in cost, and a planet carrier prepared from the nodular cast iron material can remarkably improve the service reliability of a wind power gear box and reduce the full-life-cycle maintenance cost.

The invention relates to the technical field of nodular iron casting hardness detection, in particular to a nodular iron casting hardness detection device. The mounting frame is fixedly mounted on the machine table; and the hardness meter is fixedly mounted on the mounting frame. According to the device, the positions of the grinding plate and the adsorption cleaning body are adjusted through the adjusting assembly, on one hand, different detection positions of the surface of the tubular nodular iron casting are ground and cleaned, the flatness of the detection positions of the tubular nodular iron casting is improved, and a pressure head of a hardness tester is made to make uniform contact with the surface of the tubular nodular iron casting; the accuracy of a detection result is improved; and on the other hand, oil stain cleaning on different detection positions on the surface of the tubular nodular iron casting is realized, and the cleanliness of the detection positions of the tubular nodular iron casting is improved, so that the accuracy of a detection result is further improved.

The invention provides a production method of high-strength nodular cast iron and belongs to the technical field of metal material processing. Comprising the following steps: proportioning: proportioning the following raw materials in percentage by weight: 60-70% of pig iron, 20-30% of foundry returns and 10-15% of waste steel; pig iron is added to the bottom of the furnace, foundry returns are added, and finally waste steel is added; after the molten iron is uniformly molten, heating to 1420-1440 DEG C, and sampling to analyze chemical components; inoculation and nitrogen increasing treatment: spheroidizing by adopting a pouring method, sequentially adding pure antimony, a rare earth magnesium spheroidizing agent and a mixture of ferromanganese nitride and a ferrosilicon inoculant, adding the rest of molten iron and the inoculant in stages, and adding an antimony-containing inoculant during pouring; and after pouring is completed, the box is opened for cooling when the temperature of the casting is reduced to 800-900 DEG C. According to the method, the nitrogen increasing process is matched with microalloying, the problems of high alloy adding amount and high cost in the prior art are solved, the alloy using amount can be remarkably reduced, and meanwhile the mechanical property of cast iron is guaranteed.

The invention discloses low-temperature nodular cast iron for wind power castings and a preparation method thereof, and belongs to the technical field of nodular cast iron materials. The nodular cast iron is prepared from, by mass, 3.2%-3.6% of C, 2.0%-2.5% of Si, 0.1%-0.2% of Cu, smaller than or equal to 0.3% of Mn, smaller than or equal to 0.03% of P, smaller than or equal to 0.015% of S, 0.03%-0.05% of Mg, 0.08%-0.15% of a nano additive and the balance Fe and inevitable impurities. The material matrix is mainly made of ferrite, the pearlite content is low, graphite nodules are uniformly distributed and regular in shape, and the comprehensive mechanical properties are as follows: the tensile strength is greater than or equal to 500 MPa (QT400-18AL is required to be greater than or equal to 360 MPa); the yield strength is greater than or equal to 350 MPa (the standard requirement is greater than or equal to 220 MPa); and the ductility is not less than 20% (the standard requirement is not less than 12%).

The invention relates to the technical field of metal casting, in particular to an isothermal quenching nodular cast iron ADI continuous casting method which comprises the steps that the temperature of a crystallizer used in the ADI continuous casting process is collected in real time; calculating a heat exchange coefficient in the crystallizer in real time; friction force generated when the casting blank is pulled out of the crystallizer is collected in real time; presetting each period, and obtaining period steady-state indexes of the heat exchange coefficient, the temperature and the friction force in each period; respectively acquiring abrupt change points of friction force and temperature in each period on a time sequence, and screening friction force change points and temperature change points from the abrupt change points; the lag time length of each friction force change point is obtained; the continuous casting stability index and the suspension confidence coefficient of each period are obtained; and evaluating the abnormal condition of the continuous casting process in each period through the stopping confidence coefficient of each period. According to the method and the device, the unplanned shutdown caused by misjudgment is reduced by timely finding the abnormal phenomenon in the continuous casting process, and the continuous casting production efficiency of ADI is improved.

The invention relates to a thick and large-section nodular cast iron inoculation method based on a laminated slow-release inoculation block. The method comprises the following treatment steps that S1, raw materials are prepared; s2, the high-purity pig iron, the waste steel and the nodular cast iron foundry returns in the step S1 are put into an electric induction furnace to be smelted; s3, performing carbon and silicon testing on the molten iron subjected to slag removal in the step S2 by using a carbon and silicon analyzer, and adjusting components; s4, carrying out primary spheroidizing inoculation by adopting a pouring method; and S5, after spheroidizing inoculation is completed, molten iron is poured into a sand mold, a laminated slow-release inoculation block is placed in the sand mold for slow-release inoculation, and a thick and large-section spheroidal graphite cast iron casting is formed. The method has the advantages that slow-release inoculation is implemented in the cross gate, and molten iron continuously and slowly releases an inoculant in the pouring process through the laminated slow-release inoculation blocks. By means of the method, inoculation recession can be effectively inhibited, the graphite form is improved, and finally the density and the spheroidization rate of graphite nodules in the center of the thick and large-section nodular iron casting are increased.

The invention relates to a silicon-molybdenum-vanadium nodular cast iron material and a preparation method and application thereof. The silicon-molybdenum-vanadium nodular cast iron material comprises the following components in percentage by mass: 2.9-3.4% of C; 3.9% to 4.3% of Si; mn: 0.1%-0.3%; less than or equal to 0.05% of P; s: less than or equal to 0.02%; 0.03% to 0.055% of Mg; 0.9% to 1.15% of Mo; 0.25% to 0.45% of V; cr: 0.1% to 0.25%; 0.008%-0.02% of RE (rare earth); and the balance of Fe and inevitable impurities. The tensile strength of the material at the temperature of 800 DEG C is 60-65 MPa, the ductility of the material at the temperature of 800 DEG C is 30%-45%, the linear expansion coefficient of the material at the temperature of 800 DEG C is 16-19 micrometers / (m.K), the material is low in cost, and the risk that the exhaust manifold of the heavy-duty engine loses efficacy and cracks under extreme conditions can be reduced.

The invention provides cooling equipment and process for isothermal quenching nodular cast iron production, and relates to the technical field of nodular cast iron material production, the cooling equipment comprises a cooling mechanism, a lifting mechanism, a supporting mechanism, a multifunctional mechanism A and a multifunctional mechanism B; the lifting mechanism is mounted on the cooling mechanism; the supporting mechanism is mounted on the lifting mechanism; the number of the multifunctional mechanisms A is two, and the two multifunctional mechanisms A are installed on the cooling mechanism and the lifting mechanism. The number of the multifunctional mechanisms B is two, and the two multifunctional mechanisms B are installed on the front side and the rear side of the cooling mechanism. The two rectangular protection plates automatically turn inwards under the action of the four L-shaped driving frames and the four driving gears, the automatic protection effect is achieved, steam or quenching liquid is prevented from being splashed out, and potential safety hazards are reduced; the problems that a large amount of steam is emitted during quenching and a small amount of quenching liquid is splashed due to the lack of an automatic protection structure generally, and potential safety hazards exist are solved.