106 results about "Liquidus" patented technology

The invention belongs to the technical field of electrode material preparation, and particularly relates to a preparation method of boric acid-assisted low-temperature sintered porous aluminum foil. The preparation method comprises the following steps: dispersing aluminum powder, boric acid and binder raw materials in a solvent to form dispersed slurry; and coating a matrix with the dispersed slurry, drying, sintering at 450-600 DEG C under protective gas, reacting boric acid with aluminum oxide on the surface of the aluminum powder to form low-melting-point aluminoborate, reducing the sintering temperature, promoting aluminum atom diffusion, increasing sintering neck formation, and sintering to obtain the porous aluminum foil. Boron oxide generated by decomposition of boric acid is added to react with aluminum oxide to form low-melting-point aluminoborate, the sintering liquidus temperature is reduced, aluminum atom diffusion is promoted, and low-temperature sintering at 450-600 DEG C is achieved. The aluminum powder sintered foil is suitable for energy storage devices such as an aluminum electrolytic capacitor and a lithium ion battery, has the advantages of low-temperature energy conservation, high porosity and strong mechanical property, and solves the problems of aluminum oxide obstruction and high high-temperature energy consumption of the traditional aluminum powder sintered foil.

The invention discloses a dispersion distribution method for a micro-nano multi-scale mixed SiC particle reinforced phase in an aluminum-based composite material and the composite material, and relates to the technical field of metal-based composite material preparation. The method comprises the following steps: firstly, carrying out ultrasonic cleaning, ultrasonication and two-stage high-temperature oxidation treatment on SiC particles, and generating an oxidation film on the surfaces of the particles; ball-milling and mixing the treated micron and nano SiC particles and micron pure magnesium particles according to a specific proportion, and pressing into a precast block; then preparing an aluminum alloy melt, cooling to a solid-liquid two-phase region, carrying out semi-solid stirring, and adding the preheated precast block; and finally, raising the temperature to be above a liquidus, rewarming, stirring and molding by casting. Through the synergistic effect of ultrasonic physical dispersion, high-temperature oxidation surface modification and magnesium-induced semi-solid stirring, the problems that micro-nano particles are prone to agglomeration, wettability is poor and interface reaction is difficult to control are effectively solved, multi-scale uniform dispersion distribution of a reinforced phase in an aluminum matrix is achieved, and the comprehensive performance of the composite material is remarkably improved.

The invention discloses titanium-rare earth synergistic alkali-free glass with an ultrahigh strain point and high resistance and a preparation method of the alkali-free glass, and belongs to the technical field of glass. According to the alkali-free glass, a unique titanium-rare earth synergistic enhanced network is constructed, two key control parameters, namely, a high temperature performance index (HTPI) and a resistance synergistic factor (RCF), are defined for the first time, and when the HTPI is controlled to be 5.8-7.2 and the RCF is controlled to be 3.5-4.85, the strain point of the glass is larger than or equal to 745 DEG C, and meanwhile, the glass has the advantages that the glass has the good heat resistance and heat resistance; according to the glass substrate prepared by the preparation method disclosed by the invention, the resistivity at 1620 DEG C can be accurately regulated and controlled within an ideal interval of 50-150 omega.m, meanwhile, the Young modulus is greater than or equal to 88 GPa, the liquidus temperature is less than or equal to 1260 DEG C, the comprehensive performance is far better than that of the prior art, and the strict requirements of high-generation LTPS and IGZO display panel manufacturing on the glass substrate are perfectly met.

The application discloses a near-liquid line extrusion casting forming equipment, which comprises a support, a mold closing mechanism, a driving mechanism and a screw feeding mechanism arranged on the support, wherein the screw feeding mechanism is provided with a driving cylinder on the side away from the connection with the mold closing mechanism, and the driving cylinder is provided with an adjusting mechanism capable of controlling the gas flow and the gas pressure; the adjusting mechanism increases the gas flow to realize high-speed pre-feeding of the feeding screw rod to inject the melt into the mold closing mechanism in the injection stage when the melt does not fill the mold closing mechanism, or reduces the gas flow and increases the gas pressure to realize slight pre-feeding of the feeding screw rod to compensate the melt shrinkage by pressure in the pressure maintaining stage when the melt fills the mold closing mechanism; the adjusting mechanism is controlled by a control system, and the control system is used to automatically switch the working state of the adjusting mechanism in the injection stage or the pressure maintaining stage. The application has the beneficial effects of realizing high-quality, high-efficiency and high-stability production of the near-liquid line extrusion casting.

This invention discloses a method, apparatus, and storage medium for optimizing the formulation of erosion-resistant concrete. The method includes establishing a mechanism model of molten material erosion of concrete; selecting multiple concrete components based on the molten material erosion mechanism model; composing concrete with different formulations based on the multiple concrete components; calculating the equilibrium temperature and liquidus temperature of the mixture composed of the concrete and the molten material when thermal equilibrium is reached during the interaction between the molten material and the concrete with different formulations; and determining the optimal formulation of the concrete based on the equilibrium temperature and liquidus temperature of the mixture. Concrete prepared using this invention exhibits a significantly lower erosion rate than ordinary nuclear power plant concrete, thus improving the nuclear power plant's ability to respond to severe accidents.

This invention proposes a method for preparing cement clinker based on fluorite, belonging to the field of cement production technology. Through steps such as fluorite raw material pretreatment and particle size classification, co-grinding of fluorite and raw meal, dynamic adjustment of fluorite admixture, clinker firing, and rapid cooling to obtain the finished product, fluorite is uniformly dispersed in the raw meal system, stably exerting its mineralization effect. This can reduce the liquidus appearance temperature by 50-80℃, reduce the clinker sintering temperature by 50-100℃, significantly promote the formation and development of core strength minerals such as C3S, shorten the clinker firing time, and improve the production efficiency of the kiln system.

The invention belongs to the technical field of glass manufacturing and detection, and discloses yttrium-containing aluminosilicate glass with low liquidus temperature, a preparation method and a glass cover plate, the glass comprises SiO2, Al2O3, B2O3, Li2O, Na2O, MgO, P2O5, ZnO, TiO2, SnO2, Sb2O3, La2O3 and Y2O3, and the yttrium-containing aluminosilicate glass is obtained through melting treatment, coarse annealing and devitrification sample preparation. The glass has the elasticity modulus higher than 80 GPa and the transmittance higher than 90%, the liquidus temperature is effectively reduced by adjusting the proportion of part of materials, forming is promoted, the production requirements of a production line are met, and the prepared glass can be applied to the field of mobile phone cover plates and vehicle-mounted glass and has wide application prospects. And theoretical basis and reference value are provided for research and production of yttrium-containing aluminosilicate glass.

The invention relates to a method for pulling a single crystal from a melt consisting of silicon and a dopant according to the Czochralski method, comprising the following steps in a given sequence: a) performing a time-dependent computer simulation of a predetermined crystal pulling process having a predetermined dopant concentration (C) in the melt, with the aim of obtaining a temperature gradient and a dopant gradient for each time increment t, wherein the two gradients are determined at the interface between the crystal and the melt in the normal direction of the melt interface, b) determining a maximum dopant concentration (Cmax) in the melt, and c) pulling up a single crystal having a dopant concentration less than the determined maximum dopant concentration (Cmax), characterized in that a parameter (CS) is calculated for each time increment t, which is determined by formula, wherein the parameter fCS is determined from the product of the average concentration (C) of the dopant in the melt, the density of the silicon melt, the Avgamde constant, the molar mass of the silicon and the slope of the liquidus, and then generating an average value of the values obtained for the parameter (CS) wherein only those values having the (CS) value less than zero are included, and determining the maximum dopant concentration (Cmax) by adapting the above defined dopant concentration (C) until the magnitude equals zero.

A fusible link element (10; 15; 25; 35) comprising a metal composite material in which a first fusible metal (11; 21; 31) and a second fusible metal (12; 22; 32) are layered on top of each other, wherein the second fusible metal (12; 22; 32) has a lower melting temperature than the first fusible metal (11; 21; 31), characterized by the fact that the first fusible metal (11; 21; 31) is a Sn-Ag alloy and the Sn-Ag alloy contains at least 20 wt% and at most 30 wt% Ag, and the second fusible metal (12; 22; 32) is a Sn-Bi alloy and the Sn-Bi alloy contains at least 40 wt% and at most 70 wt% Bi, wherein at a common working temperature at least part of a component of the second fusible metal (12; 22; 32) is melted and part of a component of the first fusible metal (11; 21; 31) is melted, and where, at the common working temperature, the difference between a liquidus temperature and a solidus temperature of the first fusible metal (11; 21; 31) and the second fusible metal (12; 22; 32) is reduced by a shift in the equilibrium of Sn between the first fusible metal (11; 21; 31) and the second fusible metal (12; 22; 32) and by a mutual diffusion of Ag and Bi between the first fusible metal (11; 21; 31) and the second fusible metal (12; 22; 32).

This invention discloses a lightweight, high-strength Ni-Co-based single-crystal high-entropy alloy and its preparation method. The chemical composition of this single-crystal high-entropy alloy includes eight elements: Ni, Co, Cr, Al, Ti, Mo, W, and Hf. The atomic percentages of each element are: Ni 45-55 at%, Co 15-20 at%, Cr 9-12 at%, Al 9-12 at%, Ti 4-8 at%, Mo 1-2 at%, W 0-1 at%, and Hf 0-0.1 at%. The preparation method includes the following steps: obtaining the liquidus temperature through simulation calculation and the eutectic dissolution temperature through melting point testing; sequentially placing the elemental elements Ni, Co, Cr, Ti, Mo, and W into a crucible in a vacuum induction melting furnace and casting them into a master alloy ingot; and preparing a grain with a specific orientation using the Bridgeman high-speed solidification method and the seed crystal method. <001> A single-crystal high-entropy alloy test rod was prepared; the single-crystal high-entropy alloy test rod was subjected to solution treatment, first-stage aging, and second-stage aging in sequence to obtain a lightweight, high-strength Ni-Co-based single-crystal high-entropy alloy. The single-crystal high-entropy alloy prepared by this invention has a low density and excellent room-temperature and high-temperature mechanical properties.

The invention discloses a high-strength high-temperature-resistant brazed die-casting aluminum alloy and a preparation method and application thereof, and belongs to the technical field of aluminum alloy materials. According to the high-strength high-temperature-resistant brazed die-casting aluminum alloy provided by the invention, the proportion of a eutectic phase to a primary crystal phase is controlled by controlling the proportion of Fe, Ni, Mn and RE, so that the strength of the alloy is regulated and controlled. The high-strength high-temperature-resistant brazed die-casting aluminum alloy can form good metallurgical bonding with Al-Si series brazing filler metal, the brazing filler metal and base metal are welded well, pores and cracks on the bonding surface are few, and the brazing filler metal has excellent wettability on the base metal. The high-strength high-temperature-resistant brazed die-casting aluminum alloy has the advantages of being high in solid / liquid phase line, high in strength, good in forming performance and the like, a casting is not melted or deformed after being brazed at high temperature, and the high-strength requirements of thermal management systems such as runner plates, liquid cooling plates and refrigerant branch plates in the market can be met.

To provide a protection element in which a fusible conductor is not fused even through a reflow process, and the fusible conductor can be fused quickly when abnormal.SOLUTION: A protection element 1 includes an insulating substrate 2, a heating element 5, a first electrode 3 and a second electrode 4 laminated on the insulating substrate 2, a heating element extraction electrode 6 provided on a current path between the first and second electrodes 3 and 4 and electrically connected to the heating element 5, and a fusible conductor 7 mounted on the first electrode 3, the second electrode 4, and the heating element extraction electrode 6 and fused by a self-heating caused by heating or overcurrent of the heating element 5 to block the current path. The fusible conductor 7 is formed of a laminated body 13 including at least a low melting point metal layer 11 having a liquidus temperature of less than 260°C and a high melting point metal layer 10 having a liquidus temperature of more than 400°C, and the laminated body 13 has a material configuration in which a liquidus temperature of an alloy composition when melted as a single alloy is 300°C or more and 400°C or less.SELECTED DRAWING: Figure 1

The invention relates to the technical field of brazing, and provides Zr-Ti-Hf-Ni-Cu-Co medium-entropy alloy brazing filler metal used for pure titanium and titanium alloy brazing and a using method of the Zr-Ti-Hf-Ni-Cu-Co medium-entropy alloy brazing filler metal. The invention provides Zr-Ti-Hf-Ni-Cu-Co medium-entropy alloy brazing filler metal. The brazing filler metal comprises the following components in percentage by weight: 9.5-13.9% of Ti, 0.5-1.5% of Hf, 0.5-1.5% of Ni, 0.5-1.5% of Cu and the balance of Zr. Ni: 5.5 to 9.5%; 5.0 to 9.5 percent of Cu; 2.0 to 8.5 parts of Co; 0 to 0.6% of Hf; zr: the balance. The brazing filler metal has the following technical effects that the liquidus temperature of the brazing filler metal ranges from 769 DEG C to 782 DEG C, the brazing filler metal is easily formed into amorphous brazing filler metal alloy, and the shear strength of a pure titanium-titanium alloy connector obtained after heat preservation is conducted for 10 minutes at the brazing temperature of 810 DEG C to 828 DEG C reaches 243 MPa to 280 MPa.

The invention discloses a magnesium-silicon-aluminum submersed nozzle lining material which comprises the following components in percentage by mass: 88%-98% of a base material, 1-10% of an additive; 0.5%-3% of a melting point regulator; the matrix material comprises MgO-SiO2-Al2O3 ternary components which are distributed in a range limited by a connecting line of four specific points A, B, C and D of a MgO-SiO2-Al2O3 ternary phase diagram and two liquidus lines at 1600 DEG C and 1700 DEG C; the method can be applied to continuous casting submersed nozzles, can also be applied to the high-temperature-resistant industry fields such as anti-blocking of steel ladle long nozzles adopting aluminum deoxidized steel and anti-nodulation of tundish stopper rods, and solves the problem that the submersed nozzles are easy to nodulate and block in the pouring process of aluminum deoxidized steel such as automobile sheets at present; the volume density of the magnesium-silicon-aluminum submersed nozzle lining material is 2.65-2.80 g / cm < 3 >, the apparent porosity is 10-15%, and the thermal shock resistance is gt; and 10 times (1100 DEG C-water cooling) are carried out, and the number of continuous casting furnaces in the actual use process is 8-15 times.

The application belongs to the technical field of aluminum smelting, and specifically provides a method for detecting initial crystallization temperature of electrolyte, which comprises the following steps: preparing electrolyte powder from electrolyte to be detected, melting the electrolyte powder to obtain liquid electrolyte; gradually reducing the temperature of the liquid electrolyte, and measuring the viscosity of the liquid electrolyte to obtain the viscosity value of the current temperature every time the temperature is reduced by a preset temperature; drawing a viscosity curve of the liquid electrolyte based on the viscosity values of various temperatures, wherein the viscosity curve is used to represent the relationship between the viscosity of the liquid electrolyte and the temperature; and determining the initial crystallization temperature of the electrolyte to be detected based on the viscosity curve. The technical scheme provided by the application can improve the accuracy of the detection of the initial crystallization temperature of the electrolyte.

The invention discloses a preparation method of a rare earth-containing AlMgSi alloy based on pulse electromagnetic solidification and the AlMgSi alloy, relates to the technical field of metal metallurgy, and aims to solve the technical problems that the AlMgSi alloy prepared by the prior art is poor in precipitated phase distribution uniformity and low in alloy structure refinement rate, so that the AlMgSi alloy cannot meet the use requirements of high performance and high homogenization. The preparation method of the rare earth-containing AlMgSi alloy based on pulse electromagnetic solidification comprises the following steps: preparing metal raw materials according to the composition and weight percentage of the AlMgSi alloy; after metal raw materials of the AlMgSi alloy are smelted into molten aluminum, pulsed magnetic field treatment is carried out on the molten aluminum above a liquidus of the molten aluminum, and the AlMgSi alloy is obtained after cooling; in the pulsed magnetic field treatment process, the molten aluminum is controlled to contain 0.1 wt% of lanthanum-cerium mixed rare earth, and the mass ratio of lanthanum to cerium in the lanthanum-cerium mixed rare earth is 1: (0.5-2).

A first pre-sintered body composed of a powder made of a first Ni-based alloy is prepared, and a second pre-sintered body composed of a powder made of a second Ni-based alloy is prepared. Subsequently, the first and second pre-sintered bodies are positioned to face each other across a predetermined gap, and a joining material made of a Ni-based alloy having a lower liquidus temperature than the first and second Ni-based alloys is placed in a space that adjoins the first and second pre-sintered bodies and to which the gap opens. After the placing of the joining material, the first and second pre-sintered bodies are heated to melt the joining material, fill the gap with the molten joining material, and subsequently turn the first and second pre-sintered bodies into first and second sintered bodies, respectively.

To provide a method for producing molten iron with which reduced iron having low carbon concentration can efficiently be melted.SOLUTION: In the method for producing molten iron by melting reduced iron having a carbon concentration of less than 1 mass% in an electric furnace, the reduced iron is charged into the molten iron under the condition that the difference Δ T (°C) between the temperature of the molten iron before charging the reduced iron and the liquidus temperature of the molten iron satisfies Δ T> 15-5C when the carbon concentration in the reduced iron is C (mass%).SELECTED DRAWING: Figure 2

The invention relates to an aluminum alloy composite material and a preparation method thereof. The preparation method comprises the following steps that a core material and a shell material are mixed and then pressed to obtain a blank; wherein the core material is aluminum alloy particles with hollow core structures inside, the shell material is aluminum alloy powder, and the liquidus Ta of the core material is 30 DEG C or above higher than the liquidus Tm of the shell material; the blank is heated to the temperature T1 of a solid-liquid two-phase region of the shell material under the protective atmosphere, heat preservation is conducted for 20-60 min, and first-stage sintering is completed; then, the temperature is increased to T2, heat preservation is conducted for 10-30 min, and second-stage sintering is completed; wherein T1 = Tm-(0.1-0.5) delta T, and delta T is a temperature difference between a solidus line and a liquidus line of the shell material; t2 = Ta-(0.1-0.3) delta T ', and delta T' is the temperature difference between the solidus and liquidus of the core material.

The application discloses a numerical simulation method for particle dispersion in a molten pool of a laser surface remelting particle reinforced magnesium matrix composite, and belongs to the technical field of numerical simulation of particle dispersion in a molten pool of a composite material.The application solves the problem that the particle dispersion in a laser surface remelting (LSR) process of a particle reinforced magnesium matrix composite cannot be accurately predicted at present.The temperature gradient and the primary dendrite arm spacing in the molten pool are obtained based on experimental characterization, so that the liquidus and eutectic reaction temperature of non-equilibrium solidification are calculated.The liquidus and eutectic reaction temperature of non-equilibrium solidification are used to calculate the molten pool evolution in the LSR process of the magnesium matrix composite, so that the molten pool formation characteristics and the migration behavior of the particles in the molten pool can be more accurately predicted, the particle dispersion in the molten pool formation process of the particle reinforced magnesium matrix composite can be accurately predicted, and theoretical guidance is provided for in-depth understanding of the molten pool evolution process in the laser forming process of the composite material and process parameter optimization.The application can be applied to the prediction of the particle dispersion in the molten pool of the composite material.

The present disclosure relates to a high voltage vacuum tube including:a vacuum tube envelope including an interior;an anode assembly disposed within the interior of the vacuum tube envelope; anda cathode assembly disposed within interior of the vacuum tube envelope that emits an electron beam to strike a target surface of the anode assembly and form electromagnetic radiation.The high voltage vacuum tube includes a braze assembly, the braze assembly including a first component and a second component joined together by a first braze joint, the first braze joint including a composition configured to include a solidification temperature range of no more than 90° C. and a liquidus temperature in the range of 950° C. to 1060° C.; the braze joint including no more than 30.0 wt % in total of one of more precious metals selected from Au, Pd and Pt, relative to the total weight of the first braze joint.

A production method for improving transverse crack defects in cast billets, wherein the billets are obtained by continuous casting, and protective slag is added to the crystallizer during the continuous casting process. The quaternary basicity of the protective slag satisfies Equation 1, the relationship between the viscosity of the protective slag and the casting machine speed satisfies Equation 2, and the relationship between the melting temperature of the protective slag and the liquidus temperature of the molten steel satisfies Equation 3. (CaO%+MgO%) / (SiO2%+Al2O3%)=1.0~1.2(1), 0.2≤η×Vc≤0.4(2), T L -425≤T m ≤T L -395 (3). By uniformly flowing in the protective slag liquid with high alkalinity, high viscosity and low melting temperature, the reasonable cooling intensity near the meniscus of the crystallizer is controlled to avoid transverse cracks on the surface of the billet.

The invention discloses a magnesium-aluminum alloy two-way alternate casting forming method. The method comprises the steps that S1, alloy smelting and component regulation and control are conducted; s2, alternately setting casting parameters and casting for the first time; s3, alternate casting and interface control; s4, solidifying, cooling and demolding the casting; molten liquid components are monitored in real time through a spectrum analyzer in combination with a specific component detection function, and it is ensured that magnesium and aluminum alloy molten liquid components meet design requirements; the interface temperature is accurately controlled between two layers of alloy liquidus through temperature control, and good metallurgical bonding between magnesium-aluminum alloy layers is achieved; according to the solidification characteristics of the two alloys, a cooling speed function is set, internal stress concentration is effectively inhibited, and the occurrence rate of cracks, shrinkage cavities and other defects is reduced; by means of the function model of the total argon injection amount and the injection rate, the argon consumption and the argon injection rate are accurately calculated and controlled, hydrogen and inclusions in molten liquid are efficiently removed, argon waste is avoided, and the purity and the production economy are both considered.

The application discloses a kind of copper-aluminum composite strip continuous casting and rolling preparation methods of ultrasonic vibration assisted reinforcement, it is related to metal laminated composite material preparation technical field, including preheating treatment to copper strip and control liquidus temperature;The copper strip after preheating is introduced with liquidus into the casting and rolling crystallization area formed by casting and rolling roll and carries out solid-liquid casting and rolling composite;The composite strip obtained after casting and rolling is carried out hierarchical cooling;The composite strip after cooling is sequentially carried out cold rolling finishing and low-temperature stress relief annealing.The application fundamentally eliminates interface pore inclusion and oxide residue, solves the technical problem of large dispersion of bonding strength in conventional casting and rolling process;Grain refinement strengthening and interface structure optimization synergistically improve the interface mechanical properties;Effectively release the interface thermal stress generated by the difference of copper-aluminum thermal expansion coefficient, avoid interface cracking during cooling process;Bonding strength consistency is high, can meet the stringent requirements of new energy automobile battery connecting piece and other high reliability application fields.

An apparatus for extending service life of a shot chamber and for seasoning a molten alloy are provided. The apparatus can be placed on a shot chamber of a die casting machine, absorbing the impact of the molten alloy during pouring, delivering the molten alloy smoothly into a shot chamber, and seasoning the molten alloy so that the alloy can be die cast at temperatures below its liquidus. The use of such an apparatus is expected to significantly increase the service life and a shot chamber in addition to improve the mechanical properties of the resultant cast component.

The application provides a slag type dynamic coordination design method for recovering platinum group metals by a copper-nickel matte capture method, and comprises the following steps: performing phase diagram preliminary selection based on waste catalyst components to obtain a candidate slag system range; performing quantitative correction on microelement interference of the candidate slag system to eliminate the influence of microcomponents on phase equilibrium, and obtaining a homogeneous melt slag system; performing viscosity-interfacial tension coordination regulation on the homogeneous melt slag system based on matte drop sedimentation and coalescence behavior to determine an optimal slag system; and establishing a quantitative correction mechanism for microelement interference: through orthogonal interference experiment design and high-temperature quenching phase equilibrium determination, a quantitative relationship model of interference component concentration and phase equilibrium parameters (liquidus temperature offset, phase region boundary offset) is first quantitatively established, a technical problem of deviation between a theoretical phase diagram and an actual system is solved, it is ensured that the slag type can form a completely homogeneous melt under actual smelting conditions, and interference of un-melted solid phases on platinum group metal capture is avoided.

The application discloses a method for reducing loss of continuous casting of different steel grades, which comprises a refining process and a continuous casting process; each process is as follows: (1) the refining process: when smelting mixed casting steel grades, after judging whether the upper limit or the lower limit of the composition range of the next steel grade is closest to that of the previous steel grade without crossing of mixed casting furnace times, both steel grades are controlled according to the upper limit or the lower limit of the respective composition range according to the judgment result; (2) the continuous casting process: the minimum temperature of the continuous casting tundish is greater than or equal to the liquidus of the molten steel + 25 DEG C; before the previous furnace of the mixed casting furnace times is poured, full covering agent is added into the tundish; after the previous furnace is poured, the liquid level of the tundish is lowered to less than or equal to 300 mm, and the next furnace is poured again; after the next furnace is poured, the tundish is first subjected to semi-tundish casting. The method reduces the amount of judgment of the casting blank, the amount of judgment of the special steel grade and the amount of judgment of the casting blank caused by the composition of the casting blank, reduces a large amount of economic loss caused by the composition incompatibility and the judgment of the casting blank, reduces the number of small pouring times, and reduces the refractory cost, the steel material consumption and the labor intensity.

The invention provides a metal additive manufacturing molten pool temperature calibration method. The method comprises the following steps that dynamic temperature information of a molten pool in the metal additive manufacturing process is monitored through infrared thermal imaging equipment; the monitored dynamic temperature information of the molten pool is imported into a computer with data processing software, and the temperature of the molten pool is calibrated through the solid-liquid phase line temperature of the molten pool; and the temperature field information of the dynamic molten pool of the whole molten pool in the metal additive manufacturing process is obtained based on the molten pool solid-liquid phase line temperature. According to the method, the measurement precision of the thermal infrared imager on the temperature of the molten pool is improved, the trafficability and flexibility of the thermal infrared imager in the field of metal additive manufacturing are improved, a large amount of data about the temperature of the molten pool and emissivity changes can be generated in the temperature calibration process, and the accuracy of temperature calibration is improved. The data can provide rich information for researching thermophysical phenomena, material phase change and the like in the metal additive manufacturing process, and the additive manufacturing process can be deeply understood and optimized.

In a method for removing magnesium from molten aluminum according to the present invention, molten aluminum containing magnesium is produced from an aluminum raw material, and at least a portion of the magnesium in the molten aluminum is removed from the molten aluminum by using a flux. The flux is composed of fluoride salts. The melting point of the flux is 550°C or higher and below the liquidus temperature of the aluminum raw material. The flux may be a mixture of two or more types of fluoride salts.

A multi-material boss, configured for fastening of a fastener thereto, being a feature of a die cast part, comprising a boss cylinder, an augmenting cylinder, and a filler metal layer is provided. The boss cylinder is made of the same material as the die cast part having a first hardness, and has a first interior. The augmenting cylinder is made of an augmenting material having a second hardness, is fixedly secured in the first interior of the boss cylinder, and has a second interior defined by a second cylindrical shaped wall, a base rim, and a second opening. The second hardness is greater than the first hardness. The fastener is fastened to the multi-material boss via the second opening of the augmenting cylinder having the higher liquidus temperature and greater hardness.