3998 results about "Magnesium alloy" patented technology

The invention provides an automobile magnesium alloy pre-twin crystal deformation data analysis system, and relates to the technical field of data processing, and the system comprises a twin crystal correction module which is provided with a first target monitoring point and a second target monitoring point in a pre-twin crystal area, the first target monitoring point is located at a crystal boundary intersection, and the second target monitoring point is located at the center of a twin crystal zone; acquiring orientation difference angle and strain energy density difference data of the two monitoring points in real time, calculating a covariance matrix of change characteristics of the two monitoring points, and correcting a proliferation rate parameter and an orientation rotation parameter in the dynamic evolution matrix according to a correlation coefficient of the covariance matrix to obtain a corrected dynamic evolution matrix; and the optimization module is used for adjusting a hot extrusion process parameter group according to the twin crystal density gradient distribution output by the corrected dynamic evolution matrix, the parameter group comprises a mold temperature, an extrusion speed and a strain path, and the twin crystal density is dynamically controlled in a target interval. According to the invention, the complex stress state of the automobile part under the actual working condition can be accurately simulated.

The invention discloses a semi-solid injection-molded high-strength corrosion-resistant magnesium alloy and a preparation method thereof. The magnesium alloy comprises the following components in percentage by mass: 7%-8.5% of Al, 1%-4% of Zn, 0.1%-0.8% of RE, 0.02%-0.5% of Ca and the balance of Mg and inevitable impurities. Through component design and process optimization, the liquidus temperature of the alloy is lower than 610 DEG C, and the alloy is insensitive to temperature in the solid fraction interval of 20-40% and is suitable for semi-solid injection molding; the Al content is controlled to form a net-shaped Mg17Al12 phase as a corrosion barrier, and Zn and RE / Ca cooperate to achieve heat treatment strengthening and oxidation film densification. The problem that strength and corrosion resistance of a traditional magnesium alloy are difficult to consider at the same time is solved, and the magnesium alloy is suitable for high-performance light-weight components of automobiles, aerospace and the like.

The utility model relates to the field of solid hydrogen storage, and discloses a magnesium-based solid hydrogen storage tank, and magnesium-based solid hydrogen storage materials are stored in the hydrogen storage tank. A foam metal material with heat-conducting property is filled between the magnesium-based solid hydrogen storage materials. The utility model has the beneficial effects that the system heat exchange efficiency is improved, the hydrogen charging and discharging rate is increased, the cycle life is prolonged, and the safety problem caused by excessive extrusion on the container body due to expansion of the magnesium alloy material can be effectively prevented.

A structural shroud for a passenger seat assembly includes a hollow body having a first end, a second end opposite from the first end, and a central cavity between the first end and the second end. In certain embodiments, the structural shroud may include a magnesium alloy and / or an aluminum alloy, and may be formed via casting, forging, and / or additive manufacturing, among others. In some embodiments, a base frame assembly for a passenger seat assembly includes a monolithic base frame having a first leg portion and a first tube portion integrally formed with the first leg portion.

The invention relates to the technical field of alloy pouring processes, in particular to a magnesium alloy heterogeneous flow overall coordination pouring process which comprises the steps of conducting pouring numerical simulation through simulation software, optimizing pouring design and determining a composite flow guide structure, a mold temperature control scheme and an alloy component regulation and control strategy. Magnesium alloy smelting and refining are conducted; preheating the mold by using an intelligent temperature control system; during the period, the intelligent temperature control system monitors and adjusts the temperature of the mold, and the online alloy adding system and the impurity adsorption filtering device keep the components of the melt uniform and pure; and after pouring is completed, controlling the mold temperature according to a preset cooling curve to slowly and uniformly solidify the melt. The design of the bionic branch-shaped flow dividing structure, the dynamic adjustable flow guide plate and the like reduces casting defects, and the casting forming quality is improved. And on-line alloy adding and impurity adsorption filtering ensure that melt components are stable, and the casting performance is improved.

The invention provides a magnesium alloy electric drive main shell mold machining precision control method and system, and belongs to the field of precision numerical control machining. The method comprises the steps that dynamic milling force, key point temperature and position signals of all shafts are synchronously collected through a multi-source sensor; a recursive least square method is adopted to identify the dynamic rigidity and damping coefficient of the tool-workpiece system on line, and the thermal deformation drift distance is calculated in combination with a temperature signal; predicting a three-dimensional deformation error vector in real time based on the dynamic model, thermal deformation and geometric errors, and constructing a space compensation field; macro motion compensation is achieved by modifying numerical control program coordinate points, and meanwhile high-frequency micro-amplitude compensation is conducted through a spindle tail end fast tool servo system. And establishing an adaptive disturbance observer to perform online estimation on unmodeled disturbance and feed-forward compensation, and realizing online self-tuning of model parameters in combination with in-situ measurement feedback. Real-time sensing, full-band dynamic compensation and closed-loop self-adaptive control of multi-source errors are achieved, and the machining precision and long-term stability of the mold are remarkably improved.

The invention provides a novel magnesium alloy refining control system which comprises the steps that according to melt velocity field and concentration field data, a real-time data set is combined, melt state feature vectors are extracted, and an initial state feature set is generated and used for follow-up prediction and optimization processing; aiming at different sensor sampling frequencies and data formats, applying a timestamp aligned multi-source data synchronization algorithm, fusing the real-time data sets, and generating a fused data set with a unified format; according to the fusion data set and the initial state feature set, applying a long short-term memory network time sequence prediction algorithm to generate future change trend data of melt component distribution and flow state; and according to the change trend data and the initial state feature set, a refining parameter optimization model based on gradient descent is constructed, an optimized refining process parameter set is generated, and the melt state is adjusted.

The invention relates to a WE54 magnesium alloy CMT electric arc additive manufacturing process method, and belongs to the technical field of metal additive manufacturing. The method comprises the steps that 1, a CMT welding gun 1 is fixed to the front end of an automatic robot, printing parameters are set in 3DCAM software, a printing sample block is sliced through the 3DCAM software, and a printing path is planned; 2, surface oxides and impurities of a WE54 magnesium alloy substrate 12 are removed, the WE54 magnesium alloy substrate 12 is fixed to a working table top, the center and coordinate system of the WE54 magnesium alloy substrate 12 are determined through a welding wire 2 in a CMT welding gun 1, preheating treatment is conducted on the WE54 magnesium alloy substrate 12 through induction heating equipment, and the temperature is increased to 200 DEG C; and 3, a first cladding layer 10 is printed on the WE54 magnesium alloy substrate 12 through an electric arc 3 below the CMT welding gun 1, the surface is cleaned after printing is completed, and reciprocating printing of four-layer path planning is conducted in a reciprocating mode till a final printing sample block is formed. By means of the method, WE54 magnesium alloy CMT electric arc additive manufacturing is achieved, and the additive efficiency is effectively improved.

The invention discloses a multi-element low-alloying high-speed extrusion flame-retardant magnesium alloy and a preparation method thereof. The alloy comprises the following components in percentage by mass: 0.5 to 2.0 percent of Al, 0.2 to 1.0 percent of Zn, 0.1 to 1.0 percent of Mn, 0.2 to 0.8 percent of Ca, 0.2 to 1.0 percent of heavy rare earth element Y, Er or Gd and the balance of Mg and inevitable impurities. Through the synergistic effect of non-rare earth elements Al, Zn, Mn and Ca and trace heavy rare earth elements, matching of low cost, good mechanical property and flame retardant property is realized. After the alloy is subjected to optimized bipolar homogenization heat treatment, the alloy can be subjected to extrusion production at the extrusion rate of 10-30 m / min. The room-temperature ultimate tensile strength is larger than or equal to 270 MPa, the yield strength is larger than or equal to 240 MPa, the ductility is larger than or equal to 12%, and the ignition point is larger than or equal to 850 DEG C. Important support is provided for propelling the magnesium alloy extrusion material to achieve equipment lightweight and low-carbon manufacturing in the fields of rail transit, aerospace and the like.

The invention belongs to the technical field of metal materials, and particularly relates to a high-corrosion-resistance magnesium alloy plate with filiform corrosion characteristics and a preparation method of the high-corrosion-resistance magnesium alloy plate. Based on the total amount of the magnesium alloy plate, the magnesium alloy plate is prepared from the following elements in percentage by mass: 6 to 9 percent of Al, 0.05 to 0.15 percent of Sc, 0.05 to 0.15 percent of Y, 0.05 to 0.15 percent of Mn and the balance of Mg and inevitable impurity elements; the preparation method of the alloy comprises the following steps: smelting an alloy cast ingot, carrying out solution treatment on the cast ingot, extruding into a plate, and then carrying out multi-pass rolling treatment and aging heat treatment regulation. The magnesium alloy plate has a phase structure of a dispersed Mg17Al12 phase, the corrosion behavior of the magnesium alloy plate is typical filiform corrosion characteristics, and compared with traditional pitting corrosion, the magnesium alloy plate has the advantages of being small in corrosion depth and small in destructiveness. The magnesium alloy plate provided by the invention has excellent mechanical properties and corrosion resistance.

The invention discloses a method for preparing a submicron ultra-fine grain magnesium alloy through low-pressure torsion, which comprises the following steps: respectively mounting a convex die and a concave die on a linear feeding mechanism and a torsion mechanism, then driving the convex die to feed along the axial direction by the linear feeding mechanism, placing the convex die into a material placing barrel, and enabling a cross-shaped groove of the convex die to be in contact with a blank; the linear feeding mechanism drives the male die to continuously move, and the blank is subjected to upsetting deformation until the rear section of the upsetting cavity and the flow blocking belt are filled with the blank; the female die is driven by the twisting mechanism to rotate, the fixed base plate also rotates along with the female die, and an arc-shaped boss surface in the twisting and extruding cavity drives one end, in contact with the arc-shaped boss surface, of the blank to generate torsional deformation; and after one-time torsional deformation is completed, the female die is detached, the deformed blank is taken out of the female die and rotated by 180 degrees, the steps are repeated, and torsional deformation is applied to the other undeformed end of the blank through the female die. According to the method, reinforced shear stress is continuously applied to the magnesium alloy blank to achieve high-strain accumulation, the technological process is shortened, and preparation of the weak-anisotropy uniform ultra-fine grain magnesium alloy ingot blank is achieved.

The short-process magnesium alloy wire continuous extrusion preparation method comprises the following steps that a, magnesium alloy extrusion materials are prepared, the thickness of the extrusion materials is 0.03-0.1 mm, and the length of the extrusion materials is 0.3-5 mm; b) preheating an extrusion wheel, wherein the preheating temperature is 250-500 DEG C; c) continuous extrusion: continuously introducing inert gas into an extrusion cavity, then feeding the magnesium alloy scraps into the extrusion cavity, and driving the magnesium alloy scraps to pass through an extrusion die along with rotation of an extrusion wheel to extrude a wire; and d) shaping and sizing: carrying out shaping and sizing treatment on the obtained wire material to obtain the magnesium alloy wire material with the final required diameter. According to the method, the problem of lengthy magnesium wire processing flow is solved, the problem of single type of magnesium alloy wires is solved, and the problem of efficient batch production of magnesium welding wires and wires for additive manufacturing of different component systems is solved, so that industrial production of the magnesium alloy wires is realized.

The invention relates to the technical field of material testing, and discloses aluminum magnesium alloy wire strength detection equipment which comprises a base and a controller, the top of the base is provided with a fixed seat, the base is provided with a movable seat through a first telescopic part, and a tension sensor is arranged between the first telescopic part and the movable seat; clamping mechanisms and locking mechanisms are arranged at the tops of the movable seat and the fixed seat and are used for clamping and fixing the two ends of the alloy wire; an environment simulation mechanism is arranged at the top of the base and is used for simulating different environment conditions of the alloy wire during detection; the environment simulation mechanism is arranged, the temperature and humidity in the sealing cover can be accurately adjusted, the experiment environment is adjusted in real time through a temperature adjusting instrument and a humidity adjusting instrument, different environment conditions are simulated, and therefore the mechanical performance of the alloy wire under various temperature and humidity conditions is evaluated; and the accuracy and comprehensiveness of a detection result are ensured.

The invention relates to the technical field of magnesium alloys, and particularly discloses a multi-element microalloying high-strength corrosion-resistant magnesium alloy bar and a preparation method thereof. The multi-element microalloying high-strength corrosion-resistant magnesium alloy bar comprises the following chemical components in percentage by mass: 6-7% of Al, 0.1-0.15% of La, 0.1-0.15% of Ca, 0.1-0.15% of Y and the balance of Mg and inevitable impurities, the magnesium alloy bar is of a multi-phase structure, a magnesium matrix is of a close-packed hexagonal crystal structure, and the multi-element microalloying high-strength corrosion-resistant magnesium alloy bar is obtained through extrusion and bar rotary swaging deformation process treatment. The multi-element microalloyed high-strength corrosion-resistant magnesium alloy bar prepared by the invention has the advantages of high strength and corrosion resistance.

The invention provides a high-heat-conductivity and high-corrosion-resistance magnesium alloy suitable for a mobile phone middle plate and a preparation method of the high-heat-conductivity and high-corrosion-resistance magnesium alloy, and belongs to the technical field of magnesium alloy materials. The magnesium alloy is composed of, by mass, 3.0%-5.0% of Al, 1.0%-3.0% of Ce, 0.5%-2.0% of Nd, 0.1%-1.0% of Sn, impurity elements Fe smaller than or equal to 0.06%, Cu smaller than or equal to 0.004%, Ni smaller than or equal to 0.002% and the balance magnesium. After the magnesium alloy is subjected to a 7-day neutral salt spray experiment, the measured weightlessness corrosion speed is 0.236 mm / y, the yield strength reaches 150-160 MPa, the tensile strength is 250-280 MPa, the ductility is 8-12%, and the heat conductivity is 110-120 W / (m.K).

The invention discloses a magnesium air battery negative electrode component design method based on interpretable machine learning and a preparation method, and relates to the technical field of magnesium air batteries. The method aims at designing magnesium alloy components capable of improving discharge voltage and negative electrode efficiency at the same time by using an explanatory machine learning model, particularly adopting a light-weight gradient elevator algorithm (LightGBM) model and explainable analysis and combining multi-objective optimization. According to the method, the feature importance of magnesium alloy components is analyzed based on a machine learning model, the Mg-0. 5Zn-1. 5Ga component is preferably selected for contributions of Al, Zn, Ca, Ga, In and other elements to the discharge voltage and the negative electrode efficiency, and compared with a high-purity magnesium negative electrode material, the negative electrode efficiency and the discharge voltage of the magnesium alloy negative electrode material are both improved. The invention further relates to a smelting preparation method of the magnesium alloy negative electrode material, and the method is simple and easy to operate.

The invention discloses a low-cost high-strength flame-retardant magnesium alloy profile and a preparation method thereof, and belongs to the technical field of magnesium alloy materials. The magnesium alloy is prepared from the following raw materials in percentage by weight: 10.2 to 11.0 percent of Al, 0.9 to 1.1 percent of Sn, 0.75 to 1.3 percent of Ca, 0.4 to 0.8 percent of Zn, 0.1 to 0.5 percent of Mn, 0.2 to 0.4 percent of Si, 0.1 to 0.3 percent of Sr and the balance of Mg and inevitable impurities. The flame-retardant magnesium alloy does not contain rare earth elements, the prepared flame-retardant magnesium alloy is excellent in flame retardance and good in mechanical property, meanwhile, the production cost is reduced, and the flame-retardant magnesium alloy has good market application prospects.

The invention discloses a porous ceramic filter for liquid magnesium alloy purification and a preparation method thereof, and the porous ceramic filter comprises the following raw materials in percentage by mass: 70-85wt% of ceramic particles, 8-15wt% of multi-element oxide system microcrystalline glass brazing filler metal and the balance of a binder, al2O3-B2O3-SiO2-MgO-CaO multi-element oxide system microcrystalline glass brazing filler metal is adopted, under the condition of air atmosphere high-temperature calcination, a compact reaction layer containing a low-melting-point glass phase, an aluminum oxide phase, a magnesium aluminate spinel phase, a calcium aluminosilicate phase, a borate phase and a silicate phase is generated on the surfaces of ceramic particles of a porous ceramic filter through a chemical reaction; the magnesium alloy filter has high strength and good high-temperature stability, and the problems that the filter loses efficacy and magnesium alloy melt is polluted due to the fact that the filter is eroded by magnesium alloy liquid are effectively solved.

The invention relates to the technical field of magnesium secondary battery electrode materials, in particular to a microalloyed magnesium alloy negative electrode material as well as a preparation method and application thereof, and the microalloyed magnesium alloy negative electrode material comprises the following components in percentage by mass: 0.01-2.0 wt.% of Gd and / or 0.01-2.0 wt.% of Ce, 0.01-1.0 wt.% of Mn and the balance of Mg. The preparation method comprises the following steps: weighing the raw materials according to the component proportion of the microalloyed magnesium alloy negative electrode material, smelting the raw materials, pouring, and carrying out air cooling solidification to obtain a cast ingot; the raw materials comprise pure Mg, an Mg-Gd intermediate alloy and an Mg-Mn intermediate alloy, or the raw materials comprise pure Mg, an Mg-Ce intermediate alloy and an Mg-Mn intermediate alloy; and sequentially carrying out solution treatment, extrusion treatment, rolling treatment and annealing treatment on the cast ingot to obtain the microalloyed magnesium alloy negative electrode material. The material is excellent in long cycle stability, low in overpotential, environment-friendly and low in cost.

The invention relates to the technical field of magnesium alloys, in particular to a high-toughness rare earth-containing magnesium alloy and a preparation method thereof.The high-toughness rare earth-containing magnesium alloy is prepared from, by weight, 3-8 parts of Zn, 1-5 parts of RE, 0.5-3 parts of Al, 0.1-1 part of Mn, 0.05-0.3 part of Zr and the balance Mg; rE is a combination of Y, Nd and La in a mass ratio of (2-3): 1: (0.5-1). Zinc is used as a secondary main element to replace part of aluminum, efficient solid solution strengthening is achieved through high solid solubility of zinc in magnesium, meanwhile, the morphology and distribution of a precipitated phase are regulated through rare earth, a beta-MgZn2 phase is formed, the high-temperature stability is better, balance optimization of strength, toughness and corrosion resistance is achieved, meanwhile, the welding performance of the alloy is improved through combination of Y, Nd, La and Zr, and the welding performance of the alloy is improved. The hot crack tendency is reduced, the brittle phase problem of a traditional high aluminum alloy is avoided, and the corrosion resistance and the machining performance are synergistically improved.

The invention discloses an electric arc additive manufacturing method universal for ZM series magnesium alloys, which comprises the following steps of: 1, carrying out high-precision digital modeling, carrying out refined model subdivision according to geometrical characteristics of a workpiece, and carrying out targeted path planning according to a subdivision result; 2, preheating the magnesium alloy substrate, and introducing inert protective gas; 3, fixing the ZM-series magnesium alloy coiled wire in wire feeding equipment; fourthly, electric arc additive manufacturing parameters are input; 5, electric arc additive manufacturing; and sixthly, air cooling is conducted till the room temperature is reached, and the ZM-series magnesium alloy workpiece is obtained. The novel ZM magnesium alloy preparation method, namely the electric arc additive manufacturing method universal for the ZM magnesium alloy, is provided by considering the defects that the ZM magnesium alloy usually has many casting defects, low strength and the like, and according to the method, a magnesium alloy base plate is treated, and electric arc additive manufacturing parameters are controlled; the ZM-series magnesium alloy is prevented from common casting defects such as looseness and shrinkage cavities, the microstructure is fine and uniform, and the good mechanical property is achieved.

The invention provides an Al-Si series die-casting aluminum alloy based on secondary aluminum, a preparation method of the Al-Si series die-casting aluminum alloy and a structural part. The method comprises the following steps: adding industrial silicon, steel scrap and Ni into a secondary aluminum melt to obtain a mixed melt; carrying out boronizing treatment and primary refining treatment on the mixed melt; the temperature is adjusted to 710-780 DEG C, magnesium alloy waste, Sr and Al-Ti-B alloy are added, and then secondary refining treatment is conducted; and the mixed melt is subjected to die-casting treatment, and the Al-Si series die-casting aluminum alloy based on the secondary aluminum is obtained. The high-strength aluminum alloy material comprises the following components in percentage by mass: 6%-12% of Si, 0.1%-1% of Fe, 0.4%-3% of Mg, 0%-0.1% of Sr, 0%-0.3% of Ti, 0%-0.05% of B and 0%-2.5% of Ni.

The invention belongs to the technical field of material processing, and discloses a magnesium alloy casting semi-solid injection molding method and application, and the method comprises the following steps: checking and adjusting a semi-solid injection machine, a casting mold and other equipment to be in a normal state, and placing magnesium alloy particles in a designated area of a hopper; putting a long nozzle of the semi-solid injection platform into the center of a mold sprue; setting the temperature of each section of a mold temperature controller, a charging barrel and a nozzle; preserving heat for a period of time after the temperature of the charging barrel reaches a set value, so that the temperature of materials in the charging barrel is uniform; setting the injection rate, the cooling time, the material return distance and the melt pressure of the semi-solid injection machine; and after a release agent is quantitatively sprayed to the mold, a semi-solid injection program is started, and a casting is obtained. The AS41B magnesium alloy particles with good heat resistance are adopted as the raw material, the semi-solid injection molding method is combined, a melting furnace is not needed, only heating to the semi-solid state is needed, the melt temperature is low, energy is saved, the service life of a mold is prolonged, protective gas is not needed, and the manufactured casting is good in mechanical property and high in heat resistance.

The invention provides a flame-retardant magnesium alloy with efficient forming diversification and a preparation method of the flame-retardant magnesium alloy. The flame-retardant magnesium alloy comprises the following components in percentage by mass: 4.0-10.0% of Al, 0.2-1.6% of Ca, 0.01-0.5% of Mn, 0.1-1.5% of RE, less than or equal to 0.05% of inevitable impurities and the balance of Mg, and the added RE is one or any combination of Ce, Sm, La and Sr. The preparation method comprises the following steps: smelting and casting, granulating and pulping, and performing pressure injection molding. According to the preparation method, diversified efficient forming of complex curved surfaces, thin-wall parts, special-shaped components and the like can be achieved through cooperative regulation and control of components, the process and the structure, and the obtained flame-retardant magnesium alloy is compact in structure, has the multi-level structural characteristics including a spherical primary solid phase, a fine solidification secondary phase and a grain boundary net-shaped eutectic phase and meanwhile has good flame retardance and mechanical performance; the ignition point is 750-1200 DEG C, the yield strength is 130-200 MPa, the tensile strength is 230-300 MPa, the ductility is 5-20%, and the aluminum alloy is suitable for industrial production.

The invention discloses an electric arc additive manufacturing conformal temperature regulation and control device and method, belongs to the technical field of metal additive manufacturing, and aims to solve the problems of poor molten pool stability, low dimensional precision, serious heat accumulation and the like caused by temperature difference in the electric arc additive manufacturing process. The regulation and control device comprises a cooling device, a heating device, a temperature sensor, a temperature regulation and feedback device and a sliding rail which are assembled through the sliding rail and can keep synchronous movement. In the printing process, the heating device preheats the pre-walking track to enable the pre-walking track to reach a proper printing temperature; the cooling device is used for cooling the formed welding bead in real time; the temperature sensor collects the printing temperature in real time and feeds the printing temperature back to the temperature regulation feedback device, and precise temperature regulation and control are achieved. The method is suitable for additive manufacturing of multiple metal materials such as austenitic stainless steel, martensitic stainless steel and aluminum magnesium alloy, the forming efficiency, the size precision and the forming quality are remarkably improved, and the rejection rate is reduced.

The invention belongs to the field of material processing, and discloses a method for preparing microalloyed AZ31 magnesium alloy by ultrasonic treatment, which comprises the following steps: melting magnesium at 715-725 DEG C, keeping the temperature for 5-8 minutes, then heating to 725-735 DEG C, then adding Mg-50% Al intermediate alloy, after Mg-50% Al is completely melted, keeping the temperature for 8-12 minutes, slagging off, stirring to completely dissolve Mg-50% Al, continuously keeping the temperature at 725-735 DEG C, adding pure zinc, and stirring to obtain the microalloyed AZ31 magnesium alloy. After the pure zinc is completely molten, carrying out heat preservation for 8-12 minutes, then carrying out slagging-off and stirring to completely dissolve the pure zinc, finally adding Mg-30% Ca and Mg-30% Ce intermediate alloys, carrying out heat preservation for 8-12 minutes, and carrying out stirring to completely dissolve the Mg-30% Ca and Mg-30% Ce intermediate alloys to obtain an alloy melt; the alloy melt is cooled to 655-665 DEG C, heat preservation is conducted for 20-25 minutes, then an ultrasonic treatment tool head stretches into the position 18-22 mm below the liquid level of the alloy melt for ultrasonic treatment, the ultrasonic treatment power is 300-700 W, and the treatment time is 60-120 seconds; and casting and molding under a protective atmosphere to obtain a casting blank. According to the method, the problem of slow diffusion in the casting process is solved through ultrasonic treatment, the structure is homogenized, and the strength of the structure is obviously enhanced.

The invention discloses a magnesium alloy hydrogel composite scaffold, which comprises a magnesium alloy scaffold having a porous structure; the surface of the hydrogel cartilage layer is in contact with the magnesium alloy stent, and the hydrogel cartilage layer comprises methacrylated gelatin hydrogel, methacrylated hyaluronic acid hydrogel and methacrylated chitosan hydrogel. The formula of the cartilage layer simulates the components of normal transparent cartilage; and the Young modulus of the hydrogel is further improved by virtue of a unique soft and hard combined structure, and is improved by about 3 times so as to meet the mechanical strength of normal physiological cartilage. The fatigue resistance of the hydrogel is also improved due to the particularity of hardness and softness combination. And the magnesium alloy is combined with the hydrogel, so that electrochemical combination is further formed, and the magnesium alloy and the hydrogel are combined more tightly.

The invention discloses a high-rigidity Mg-Al series magnesium alloy material which comprises main alloy elements Al and Ca, the content of Ca is 15 wt.%-30 wt.%, and the mass ratio of Ca to Al is 0.4-1. Preferably, the content of Ca is 15.5 wt.%-27 wt.%, and the total content of Al and Ca is greater than or equal to 31 wt.%. By regulating and controlling the Ca content and the Ca / Al mass ratio, a high-modulus C36 or C15 phase is formed to the maximum extent, and plasticity is kept while the elasticity modulus is improved. The magnesium alloy material is high in elasticity modulus, high in rigidity and good in heat resistance, and can be applied to service scenes with higher requirements for material light weight, rigidity, dimensional stability and wear resistance.

The invention relates to the technical field of magnesium alloy material processing, in particular to a magnetic pulse generation cast-rolling casting nozzle with a solidification structure regulation effect, which comprises a casting nozzle main body unit, a transmission unit and a magnetic pulse generation unit. The motor drives the coil box to move to the position close to the roller along the guide rail, so that a pulse electromagnetic field generated by the coil accurately acts on the solidification front edge; a plurality of positioning grooves are formed in the coil box, the coil can be divided into a middle coil and an edge coil, pulse electromagnetic fields are generated by utilizing currents with different intensities and frequencies at the edge and the middle, a solidification structure generates an induced magnetic field and is subjected to the action of Lorentz force, structure exchange is formed, and the consistency of the temperatures of the middle and the edges of a cast-rolling area is guaranteed; therefore, the shape of the cast-rolling solidification welding line is regulated and controlled. The method can promote nucleation at the solidification front edge, effectively refine the solidification structure, reduce macrosegregation, improve the problem of non-uniform cooling of the casting-rolling middle part and the casting-rolling edge part and effectively inhibit magnesium alloy casting-rolling edge cracks, and has important application value in the casting-rolling field.

The embodiment of the invention provides a middle frame, a preparation method thereof and electronic equipment, relates to the field of electronic equipment, and is used for realizing reliable connection between a middle plate and an outer frame, improving the impact resistance of the middle frame and guaranteeing the consistency of radio frequency performance of a frame antenna of the electronic equipment. The middle frame comprises a middle plate, an outer frame and a connecting piece. The middle plate comprises a mounting hole. The outer frame is located outside the middle plate. The outer frame comprises a main body part and an extension part which are connected, and the extension part and the middle plate are stacked. The connecting piece is located in the mounting hole and connected with the middle plate. The connecting piece is welded with the extension part. Wherein the material of the middle plate comprises one of magnesium alloy, a magnesium-based composite material and aluminum alloy. The outer frame is made of one of aluminum alloy, a titanium-based material, an iron-based material, a titanium-aluminum composite material and a steel-aluminum composite material. And the microhardness of the connecting piece is greater than that of the middle plate. The middle frame is applied to the electronic equipment so as to improve the performance of the electronic equipment.