736 results about "Fine grain" patented technology

A pore pressure prediction method for fine-grained hybrid sedimentary rock based on variable P-wave velocity includes: carrying out a P-wave velocity test of rock under different effective stresses, determining a function form of the relationship between acoustic velocity and effective stress, fitting the parameters in the function by optimization, and establishing an evaluation model of effective stress influence term by lithology. According to the measured formation pressure data and the effective stress influence term model, the acoustic velocity background value is deduced, the logging curve is preferred, and the acoustic velocity background value logging evaluation model is established. According to the logging curves of DT and DEN, combined with the lithology identification results, the acoustic velocity background value is calculated, and then the effective stress of the formation is obtained, and then the pore pressure is determined according to the overburden pressure.

The invention discloses a Cu-Cr-Zr-TiB2 copper-based composite material and a preparation method and application thereof. A blank containing TiB2 particles is subjected to rotary forging to obtain a rotary forging piece, the rotary forging piece is subjected to primary aging treatment and then subjected to electric pulse drawing to obtain a drawing piece, and then the drawing piece is subjected to secondary aging treatment to obtain the Cu-Cr-Zr-TiB2 copper-based composite material. According to the Cu-Cr-Zr-TiB2 copper-based composite material prepared through the preparation method, the copper matrix is of a gradient structure with the surface layer being a nanocrystalline layer of 50-200 nm and the core part being fine grains of 0.5-1 micron, TiB2 particle reinforced phases are distributed in the copper matrix in a fibrous mode in the axial direction, and Cr / Zr nano precipitated phases are distributed in gaps of the TiB2 particle reinforced phases and in crystals of the copper matrix in a dispersed mode; therefore, the high-hardness, high-strength, high-conductivity, high-softening-temperature, excellent high-temperature performance and excellent arc extinguishing performance are achieved.

The invention relates to a high-permeability ultralow-coercive-force soft magnetic stainless steel heat treatment process which comprises the following steps: in a nitrogen atmosphere, firstly heating a hot-rolled wire rod to 900-950 DEG C at a heating rate of 30-50 DEG C / h, preserving heat for 4-6 hours to obtain a fine grain structure of equiaxial recrystallization ferrite, then cooling to room temperature at a cooling rate of less than or equal to 15 DEG C / h to homogenize the ferrite structure, and finally cooling to room temperature at a cooling rate of less than or equal to 15 DEG C / h to obtain the high-permeability ultralow-coercive-force soft magnetic stainless steel. The soft magnetic stainless steel is obtained. The method has the advantages that the maximum magnetic conductivity of the soft magnetic stainless steel is improved, the coercive force of the soft magnetic stainless steel is reduced, and the plasticity index of the soft magnetic stainless steel is improved.

The invention belongs to the field of advanced metal plastic processing, and particularly relates to a difficult-to-deform metal ultra-thin strip rolling device and method.The device comprises an uncoiler, a high-strength rolling mill and a coiler which are sequentially arranged, and the inlet side and the outlet side of the high-strength rolling mill are each provided with a pair of equal-diameter rollers; the equal-diameter roller is composed of a copper conductive roller and a ceramic insulating roller, the copper conductive roller on the inlet side and the copper conductive roller on the outlet side are electrically connected to the positive electrode and the negative electrode of the pulse power source respectively, and a strip blank on the uncoiling machine sequentially penetrates through the equal-diameter roller on the inlet side, the high-strength rolling mill and the equal-diameter roller on the outlet side and then is wound on the coiling machine. And a working roll, which is in contact with the strip blank, on the high-strength rolling mill is an insulating ceramic working roll. The pulse current in the method can induce dynamic recrystallization, an ultra-fine grain or nanocrystalline structure is obtained, and the strength and plasticity matching of the product is superior to those of a traditional process. Meanwhile, long-time high-temperature oxidation can be avoided by adopting pulse current to heat the strip blank, and the surface is bright.

The invention discloses a semi-solid ultrasonic rolling synchronous auxiliary electric arc additive manufacturing device and method, and the device comprises an ultrasonic rolling device, and further comprises an electric arc welding gun device, an automatic wire feeding device, a manipulator, a control system device, a protective gas cylinder and a clamp device. When semi-solid ultrasonic rolling synchronous auxiliary electric arc additive manufacturing is carried out, the electric arc welding gun is fixed to one mechanical arm, the synchronous ultrasonic rolling device is fixed to the other mechanical arm, and the two mechanical arms are controlled by the control system device to move synchronously. The invention provides a structure regulation and control method of applying ultrasound and rolling composite to a semi-solid area of an electric arc additive manufacturing near-molten pool, and utilizes stirring and cavitation effects of the ultrasound and a deformation-induced recovery recrystallization effect to promote escape of bubbles, effective welding of pores and full crushing and refining of dendritic crystals, so that the mechanical property of the electric arc additive manufacturing near-molten pool is improved. And finally, regulation and control of the compact equiaxed fine grain structure in electric arc additive manufacturing are achieved.

The invention relates to an upper and lower roller reducing independent transmission universal rolling mill and a control method thereof, and belongs to the technical field of metallurgy. The rolling mill comprises a universal rolling rough rolling unit, a middle rolling unit and a universal rolling finish rolling unit which are sequentially arranged along a rolling line, a horizontal roller set of each unit is of an upper and lower roller reducing structure and is provided with an independent transmission system, and a gearbox and a transmission shaft are driven by an independent motor to achieve roller separation control. The middle rolling unit is a reducing edging mill, and temperature control units are arranged in front of and behind the rough rolling unit and the finish rolling unit respectively. The rolling method comprises the steps of adjusting the roller diameter ratio, synchronously adjusting the dip angle of the universal spindle and the basic height of the rolling mill, conducting gradient deformation rolling, dynamically adapting to a rolling model and the like. Through cooperation of independent transmission and reducing, accurate matching of the speeds of the upper roller and the lower roller is achieved, deformation uniformity is improved, the total motor power is reduced, an adjustable cooling nozzle and intelligent model optimization are combined, a product has the surface layer ultra-fine grain structure and core toughness, and the yield and market competitiveness are remarkably improved.

The invention belongs to the technical field of metal preparation, and particularly relates to a Fe-Al-Nb alloy and a preparation method thereof. Comprising the following steps: mixing ferric oxide, niobium pentoxide powder and a metal diluent, performing ball milling, and pressing into a green body; and the blank is put into a reaction kettle, then an ignition agent is added, protective gas is inflated, a self-propagating reaction is conducted at the temperature of 260-300 DEG C, and the Fe-Al-Nb alloy is obtained. The Fe-Al-Nb alloy is prepared through the self-propagating reaction, the reaction temperature is reduced, the thermal stress during forming is improved, the temperature of the self-propagating reaction is only 260-300 DEG C, meanwhile, the self-propagating reaction mode is adopted, the alloy is rapidly cooled after reacting, the fine grain strengthening effect is promoted to be more obvious, a microstructure of a Fe3Al matrix phase and a C14 Laves reinforced phase is formed, and the Fe-Al-Nb alloy is obtained. And the distribution of a reinforced phase is more uniform, and the wear resistance of the material is improved.

The invention discloses a breathable anti-seepage structure layer suitable for roadbed slope protection. The breathable anti-seepage structure layer comprises a coarse grain layer, a fine grain layer, plant straw and a drainage ditch. The coarse-grained layer is laid on the roadbed slope, the fine-grained layer is laid on the coarse-grained layer, the plant straws are inserted into the fine-grained layer and are inserted into the interface of the fine-grained layer and the coarse-grained layer, and the drainage ditch is arranged at the position where the toe of the roadbed slope is in contact with the interface of the fine-grained layer and the coarse-grained layer; according to the invention, through two special methods of inserting the plant straws into the fine grain layer and doping the expansion material particles into the coarse grain layer, high air permeability and ultra-strong seepage prevention of the structural layer are realized, the problems of'pot cover effect 'and capillary retardation failure are effectively prevented, and the method has good economic, environment-friendly and social benefits.

The invention discloses a shield muck heavy metal pollution intelligent sorting system and method based on multi-parameter online detection, and relates to the field of shield muck sorting, the shield muck heavy metal pollution intelligent sorting system comprises a muck sample pretreatment module, an online detection module, a pollution evaluation analysis module, a sorting execution module and a linkage control feedback module; the muck sample pretreatment module is used for separating coarse particles with the particle size larger than 50 mm and impurities in shield muck through a vibrating screen. According to the method, the initial value of the fine-grained soil content is detected in real time, data is automatically corrected based on a preset intelligent densimeter and a traditional densimeter difference correction model, rapid measurement is achieved, the detection efficiency is improved, a dynamic correlation model of fine-grained soil component changes is constructed by combining auxiliary parameters such as the muck weight, the water content and coarse grain grading, and the detection accuracy is improved. And the working condition adaptation module is linked to automatically improve the fine-grained soil detection frequency when the stratum mutation is identified by the shield PLC parameters, so that the data is ensured to closely follow the stratum change.

The invention relates to the technical field of nuclear fusion surface plasma W materials, in particular to nano rare earth oxide ceramic-Ti microalloy composite reinforced W powder, a composite material and a preparation method of the nano rare earth oxide ceramic-Ti microalloy composite reinforced W powder. The composite powder is of a nearly spherical core-shell hierarchical structure, and the particle size is 30-50 nm; according to the composite powder, refractory metal W serves as a matrix, nano rare earth oxide ceramic particles are evenly dispersed in matrix W crystal grains, Ti mainly forms an enrichment area on the surface of the matrix or a matrix / rare earth oxide interface in a simple substance or oxide mode, the phase interface structure is effectively improved, W crystal boundary migration and dislocation motion are hindered, W crystal grains are remarkably refined, and the composite powder is prepared. Part and W form semi-coherence, fine grain and interface strengthening and toughening are achieved, and a brand new thought and a technical method are provided for synergistically improving the strength and toughness of the W composite material. The composite powder is subjected to organic reduction synthesis and low-temperature reinforced sintering to prepare the composite material, the tensile strength at the room temperature reaches 500-610 MPa, and the ductility is 5%-8%.

The invention discloses intelligent forging equipment and method based on seamless steel pipe machining, and relates to the technical field of needing modification. The intelligent forging equipment comprises a titanium alloy cylindrical blank roller and a temperature control mechanism used for heating the titanium alloy cylindrical blank roller; a supporting and straightening mechanism used for conducting shaping and straightening on the titanium alloy cylindrical blank roller is arranged on one side of the interior of the temperature control mechanism, and a supporting frame is arranged on one side of the temperature control mechanism. Metal can be forced to flow through the hammering acting force of the forging hammer mechanism, small gaps and holes in the metal can be filled, air holes and shrinkage porosity in materials are reduced, the overall density of the materials is improved, potential stress concentration points are reduced, and therefore the reliability of the materials is enhanced; the titanium alloy is subjected to repeated plastic deformation, so that original coarse grains are crushed into finer grains, and grain refinement is beneficial to improving the strength and toughness of the material.

The composite force field magnetic separation column comprises a separation cone frustum, the separation cone frustum is of a hollow structure, and a magnet device and a rotating shaft are arranged in the separation cone frustum; the magnet device is cylindrical and is arranged between the sorting cone frustum and the rotating shaft, and the rotating shaft is movably connected with the magnet device; a sorting screw is wound on the outer side of the sorting cone frustum, a blade of the sorting screw is fixedly connected with the rotating shaft, and the sorting screw can rotate relative to the sorting cone frustum; the bottom of the rotating shaft is connected with the transmission device and used for driving the sorting screw to rotate. The bottom of the sorting spiral is close to the feeding belt, and materials on the feeding belt are conveyed upwards through rotation of the sorting spiral. And an air blowing device is arranged on one side of the separation screw, so that non-magnetic materials or weakly magnetic materials on the separation cone frustum or the separation screw are blown away from the separation screw, fall to a tailing falling area and are taken away from a working area through a tailing belt, and magnetic concentrate products at the uppermost end of the separation screw are conveyed to a concentrate product area through a concentrate belt.

The invention relates to a stirring friction pretreatment method for an aluminum alloy diffusion welding grain refinement surface, which comprises the following steps: starting from edge lines of a pair of to-be-welded surfaces of an aluminum alloy to-be-welded part, respectively carrying out multi-pass continuous equidistant stirring friction processing on the pair of to-be-welded surfaces, and ensuring that the translation overlapping rate of a stirring needle track between passes is 25-50%; during friction stir processing, water is continuously added for cooling, so that a spiral deformed fine grain layer with the grain size of 50-80 microns and the thickness of 1-2 mm is generated on a pair of to-be-welded surfaces at the position of a columnar stirring needle; and milling the pair of surfaces to be welded after the stirring friction processing is completed until the roughness is Ra 0.1-Ra 0.3, so as to obtain the aluminum alloy diffusion welding grain refinement surface. Compared with a welding seam obtained through a direct diffusion welding method, the welding seam obtained through the method has the higher welding rate and the higher strength, a new thought is provided for production and manufacturing of aluminum alloy, and the method has important significance in improving performance indexes and enhancing service reliability.

The invention relates to the technical field of hastelloy, in particular to a preparation method of a large-caliber seamless hastelloy thin-wall roller body, which comprises the following steps of: 1) performing vacuum centrifugal casting on an alloy blank sleeve; (2) carrying out thermal solution treatment on the alloy blank sleeve; (3) machining the pipe blank; (4) powerful spinning is conducted, specifically, a powerful spinning machine is used for conducting spinning on the pipe blank for more than three passes; and 5) annealing heat treatment. Fine grains are prepared through multi-pass spinning and low-temperature annealing, the strength and toughness of the material are improved through fine grain strengthening, the grains in all directions of the hastelloy conductive roller are uniform and consistent, and the average grain size is smaller than or equal to 10 microns; the tensile strength is greater than or equal to 800MPa; the yield strength is greater than or equal to 600MPa; the ductility is not less than 20%.

The invention discloses a pyrochlore structure high-entropy ceramic solidified body material as well as a preparation method and application thereof, and belongs to the technical field of nuclear waste solidification. The preparation method of the high-entropy ceramic solidified body material with the pyrochlore structure comprises the following steps: weighing raw material powder of La2O3, Nd2O3, Sm2O3, Gd2O3, Eu2O3 and ZrO2 according to the proportion in (La0. 2Nd0. 2Sm0. 2Gd0. 2Eu0. 2) 2Zr2O7; the weighed raw material powder is subjected to ball milling treatment, and ball-milled powder is obtained; under the inert gas atmosphere, the ball-milled powder is subjected to heat treatment, and heat-treated powder is obtained; and carrying out spark plasma sintering on the heat treatment powder to obtain the pyrochlore structure high-entropy ceramic solidified body material. The powder is treated by using a heat treatment technology, so that the powder is homogenized, a pyrochlore phase is formed, grain growth is more favorably inhibited, a fine grain structure is obtained, and the irradiation stability and the mechanical property of the pyrochlore material are improved.

The present disclosure relates to the technical field of powder metallurgy, especially to a coarse grain cemented carbide and a preparation method thereof. Pseudo particles in coarse grain tungsten carbide are removed by pretreating process. Broken of the coarse grain tungsten carbide in traditional wet milling is avoid by solid-liquid stirring, spay granulating and surface covering, which also guarantee the uniform distribution of PEG and cobalt salt. Transformation from cobalt salt to cobalt is safely and effectively guaranteed by performing two sintering stages with different atmosphere and temperature to obtain a WC—Co mixture material. By performing spark plasma sintering process, the precipitation of nano fine grain tungsten carbide guarantees regrowth of defect occurred in pretreating process. The coarse grain cemented carbide with the average grain size of WC above 10 μm, the uniform cobalt phase distribution and be bending strength not less than 2200 MPa is prepared.

The invention provides a preparation method of a copper target material, and belongs to the technical field of metal target material preparation. According to the preparation method of the copper target material, the copper blank is subjected to hot rolling, thick columnar crystals in an original as-cast structure of the copper blank are crushed into fine grains through hot rolling, and the grain structure is more uniform; and the total volume of gaps among crystal grains is rapidly reduced, an original loose structure is compacted into a compact structure, densification treatment of the copper blank is achieved, and the dislocation density of the copper blank is increased. And then the copper target blank is cooled to 25-40 DEG C and then is subjected to cold rolling, crystal grains in the copper target blank are further rearranged, gaps between the crystal grains are further compressed, the crystal grain structure of the copper target blank is more compact, and the dislocation density is further improved. And finally, a temperature stepped annealing process is adopted, so that internal stress generated in the hot rolling and cold rolling processes can be effectively eliminated, and the hardness of the copper target blank cannot be excessively reduced due to the annealing process.

The invention discloses a method for purifying feldspar concentrate through superconducting high-intensity magnetic separation, which belongs to the technical field of purification of high-quality industrial raw materials and comprises the following steps of crushing, ore grinding, desliming, high-intensity magnetic roughing, high-intensity magnetic concentration, grading, fine particle high-intensity magnetic concentration and solid-liquid separation and dehydration. Aiming at the differences of hardness, granularity, dissociation degree, specific susceptibility and the like between the feldspar ore and associated minerals contained in the feldspar ore, a reasonable physical mineral separation process is selected, and the raw ore is selected into three products, namely a building raw material which can be used as raw materials of cement, aerated bricks and the like, and a medium-grain feldspar concentrate and a fine-grain feldspar concentrate which can be used as raw materials of photovoltaic glass; in addition, all the processes are environment-friendly physical ore dressing, no pollution is generated, a flotation process is not needed, zero emission of tailings and tail water is achieved, and the method is suitable for large-scale production and application.

The invention discloses a novel belt filter press loosening device for fine coal, which comprises a bottom plate, the upper side of the bottom plate is fixedly connected with a slope, the upper sides of the front and rear ends of the slope are fixedly connected with vertical plates, the upper sides of the vertical plates are provided with dispersing units, and the dispersing units comprise connecting plates. The connecting plate is fixedly connected between the two vertical plates, a lifting block is slidably connected to the outer side of the connecting plate, and a lifting plate is fixedly connected to the upper side of the lifting block. According to the novel belt filter press material loosening device for the fine coal, by arranging the vertical plate, the connecting plate, the lifting block, the lifting plate and the dispersing plate, fine coal materials can be conveniently guided into a feeding hopper of a belt filter press, the dispersing plate is controlled to reciprocate in the up-down direction and the left-right direction through the connecting frame, the rotating wheel, the first rotating plate, the second rotating plate and the control plate, and the fine coal materials can be conveniently dispersed; and the fine coal materials are uniformly distributed in the filter press, so that the filtering effect is improved.

The invention relates to the field of material processing, in particular to a continuous winding graphene metal composite wire roll-extrusion forming method and equipment, and the equipment comprises a base material conveying module, a base material pretreatment and winding integrated module, a covering material conveying and pretreatment integrated module, a heat treatment module, a roll-extrusion forming module and a material pulling module. The six modules are connected and combined together through the discharging ports and the feeding hopper, after metal wires are pretreated, the metal wires are extruded and rotated while being driven to advance, the metal wires are wound with the covering material, multi-dimensional and multi-size covering can be carried out on the metal wires, and the covering efficiency is improved. Pretreatment and roll extrusion forming of a base material and a covering material can be continuously carried out in one procedure, the consumption of graphene is reduced, the coated graphene is separated into a thin layer or even a single layer under the action of shear force in the rotary extrusion friction process, the conductivity and mechanical performance of the composite wire are greatly enhanced, and the service life of the composite wire is prolonged. And finally, the graphene metal composite wires and bars with excellent performance and uniform and fine crystal grains are prepared, the coating success rate is increased, meanwhile, the production efficiency is improved, and the method is high in flexibility and easy to repair and maintain.

The utility model provides a processing device for aluminum pipe weld joints, which comprises a base and a driving motor, a support is inserted into the top of the base, brackets located on two sides of the support are arranged on the top of the base, a V-shaped plate with a small end facing the base is arranged on the top of one side of the support, and supporting wheels are arranged at the free end and the sharp corner of the V-shaped plate. One side of the V-shaped plate is connected with a tensioning wheel located in the V-shaped plate through a tensioning rod. According to the utility model, the V-shaped plate, the supporting wheel, the tensioning wheel and the grinding belt are arranged, the grinding belt is positioned into the V-shaped groove structure by the supporting wheel and the tensioning wheel, when a welding seam needs to be ground, an aluminum pipe is placed in the V-shaped groove structure, the running grinding belt containing coarse grains can grind the welding seam, and when the welding seam needs to be polished, the grinding belt containing fine grains is replaced for polishing treatment. Compared with the prior art, the device has the advantages that the grinding belt is saved, and the appearance quality after grinding is better.

The invention relates to the technical field of material microstructure characterization, and discloses a method for improving ultrafine grain steel bar metallographic detection precision, which comprises the following steps: exciting a nanometer sonoluminescence probe covering the surface of a sample by using a focused sound field, and carrying out global scanning to obtain a reference grain boundary network image; automatically identifying regional interest points including a crystal boundary three-fork point and a signal interruption region from the image; aiming at different types of interest points, adaptively reconstructing a sound field mode or a scanning mode, and carrying out enhancement detection to obtain quantitative diagnosis information of the interest points; and finally, a multi-level interactive report integrating global morphology, key point labeling and local diagnosis is generated. According to the method, the uncertainty of a traditional chemical corrosion method is solved, an intelligent detection normal form from global general survey to local fine survey is realized, the recognition precision and diagnosis capability of defects such as early-stage microcracks are improved, and an objective, accurate and quantitative basis is provided for material performance evaluation.

The invention discloses a method for preparing coal and calcined kaolin through coal gangue grinding and grading-acid leaching-suspension calcination, and belongs to the technical field of coal gangue beneficiation. According to the method disclosed by the invention, the three stages of ore grinding flotation, acid leaching purification and fine grinding calcination complement each other, so that fine-grained calcined kaolin of which the content of-7 microns is greater than or equal to 90% and the whiteness is greater than or equal to 90% and ultrafine-grained calcined kaolin of which the content of-2 microns is greater than or equal to 90% and the whiteness is greater than or equal to 90% are prepared. According to the method, effective separation of coarse coal, leaching and purification of impurity iron elements and calcination and purification of fine-grained kaolin are realized through step grinding and step separation; the gas-solid reaction degree is improved and sintering is avoided by utilizing the dispersion and suspension characteristics of fine-particle materials; the dehydroxylation and decarburization reactions can be carried out completely by calcining fine materials and precisely controlling the temperature, so that the whiteness of the calcined kaolin product is remarkably improved. According to the method, the adaptability to coal gangue raw ore is improved, and meanwhile, a new thought is provided for efficiently preparing a calcined kaolin product from the coal gangue and cooperatively recycling coal resources.

The invention relates to a method for lithium recovery and tailing-free treatment of spodumene mill tailings, and belongs to the technical field of waste resourceful treatment. When the content of lithium in the spodumene mill tailings is 0.3 wt% or above in terms of Li2O, the method comprises the steps of magnetic separation, graded concentration and sieving, and coarse-grained materials are returned to serve as spodumene raw ore to be recycled; mixing the fine-fraction slurry with the overflow slurry, and performing solid-liquid separation to obtain a ceramic raw material; when the content of lithium in the spodumene mill tailings is less than 0.3 wt% in terms of Li2O, the method comprises the following steps: performing magnetic separation on the spodumene mill tailings to obtain a magnetic iron-rich material and iron-removed tailing slurry; and carrying out solid-liquid separation on the iron-removed tailing slurry to obtain the ceramic raw material. According to the method, the environmental protection and safety problems of lithium loss in the spodumene tailings in the production process, large pressure of storage or stockpiling of the lithium tailings and the like are solved, the lithium recovery rate is increased, meanwhile, the lithium mineral separation tailings are comprehensively utilized, and the spodumene mineral separation is free of tailings.

The invention belongs to the field of engineering materials, and discloses an ultrahigh-strength steel plate with yield strength of 1500 MPa for engineering machinery and a manufacturing method of the ultrahigh-strength steel plate. Through reasonable component design and combination with proper rolling reduction, finish rolling temperature and quenching temperature, the microalloying effect of Nb, V and Ti is fully utilized, ultra-fine grain martensite is obtained, the effects of fine grain strengthening, precipitation strengthening and dislocation strengthening are fully exerted, the effects of C and alloy are exerted, and the Q1500 steel plate with the low carbon equivalent CEV is obtained. By means of the process, the high-strength steel plate which is good in production performance, easy to weld, 5-20 mm thick, 1500 MPa in yield strength and used for engineering machinery can be stably produced, and the high-strength steel plate is widely applied to large engineering machinery equipment such as crawler cranes and wheeled cranes.

The invention discloses a multi-stage circulating graphite flotation process which specifically comprises the following steps: S1, coarsely crushing a graphite mineral material containing crystalline flake graphite, then feeding the graphite mineral material into a screening machine for grading, separating out oversize coarse grain products and undersize fine grain concentrate, carrying out screening treatment on the oversize coarse grain products again through scavenging equipment, and screening the oversize coarse grain products to obtain oversize fine grain concentrate and undersize fine grain concentrate; then feeding undersize fine-grain concentrate and scavenged materials into a grinding machine for crushing and grinding treatment, and discharging the ground materials from a discharge port; s2, separation flotation; and S3, ore grinding and flotation. The invention relates to the technical field of purification of graphite in nonmetallic minerals. According to the multistage circulating graphite flotation process, the flotation efficiency can be greatly improved by simplifying the flotation process, the flotation effect can be greatly enhanced by adopting the flotation agent, and the graphite flotation process is simple in flotation procedure, good in flotation effect and high in practicability. Concentrate and tailings can be subjected to more sufficient flotation treatment by utilizing the flotation agent.

The invention relates to a method for preparing a high-strength and high-conductivity powder metallurgy copper-iron alloy from copper-coated iron powder, and belongs to the technical field of electrochemistry and powder metallurgy materials. S2, preparing a copper source solution; s3, mixing and replacing powder and liquid; s4, performing two-stage reduction; s5, powder raw material mixing; s6, pressing and forming the raw materials; s7, sintering and densifying; s8, deformation processing treatment; and S9, high-temperature heat treatment. According to the method for preparing the high-strength and high-conductivity powder metallurgy copper-iron alloy through the copper-coated iron powder, the prepared copper-coated iron composite powder is uniform in coating layer structure and good in compactness, and compared with a replacement copper plating method, a large number of loose copper block heterogeneous distribution does not occur on the surface; and secondly, the prepared copper-iron alloy billet is low in oxygen content, high in sintering density, uniform in component, free of segregation, small in grain size, excellent in processability, few in residual solid solution iron atoms in copper, high in strength and high in conductivity, and has important application prospects in key components in the fields of electronic information, aerospace, electromagnetic shielding and the like.

The invention discloses a polycrystalline tungsten cutting surface performance regulation and control method which comprises the following steps: selecting high-purity tungsten powder, carrying out heat treatment after high-temperature sintering, removing an oxidation film and a rough layer to obtain a polycrystalline tungsten blank, selecting the polycrystalline tungsten blank with qualified density, carrying out high-temperature heating, carrying out forging, refining the average grain size of polycrystalline tungsten, and after the forging is finished, carrying out heat treatment on the polycrystalline tungsten powder to obtain the polycrystalline tungsten cutting surface performance. And the fine-grain tungsten sample is subjected to annealing treatment, the fine-grain tungsten sample is polished, and the fine-grain tungsten sample obtained after treatment is subjected to single-point diamond turning. According to the fine-grain tungsten treated through the high-temperature forging process, microcrack propagation can be effectively restrained, surface defects are reduced, then the surface integrity of a turned sample is improved, a continuous ultra-fine grain surface layer can be generated on the surface, and the irradiation resistance and corrosion resistance of the fine-grain tungsten are improved.

The invention discloses a titanium carbonitride-based metal ceramic alloy with a dispersive distribution micro-nano twin-crystal core ring structure and a preparation method thereof, the metal ceramic alloy comprises hard phase powder, hard phase powder, hard phase powder and hard phase powder, the hard phase powder comprises TiCN powder, TiC powder and WC powder, and the hard phase powder comprises TiC powder, TiC powder and WC powder; binding phase powder and multi-component alloy strengthening powder. According to the core-ring shell composite crystal grain, the core is 50-200 nm superfine TiCN crystal grains (high-hardness phase), and basic strength is provided; according to the annular shell, the core is wrapped with the oriented-growth TiCN whiskers with the large length-diameter ratio, the whisker bridging effect is formed, and the crack path is deflected. And dispersion bicrystal distribution: micron-sized coarse grains and submicron fine grains are in bimodal distribution according to the volume ratio of 7: 3, the coarse grains hinder crack propagation, and the fine grains inhibit grain boundary slippage. In-situ reaction strengthening: MoSiB and other components are added, a MoO / TiO self-lubricating film is generated in high-temperature friction, the wear rate is reduced, and negative wear is realized.

The invention relates to a cooperative control method and equipment system based on direct current casting-warm rolling direct connection, and belongs to the technical field of metal material machining. The system comprises a melting furnace, a standing furnace, a crystallizer, an electromagnetic stirrer, a four-roller warm rolling machine, a coiling furnace and other core units which are connected in sequence. The technological process comprises the key procedures of melt preparation, casting blank forming, online detection, warm rolling machining, heat treatment and the like. By innovatively adopting the electromagnetic stirring and direct current casting cooperative control technology and the continuous drawing and warm rolling integrated design, the technical problems of casting nozzle blockage and short service life in the traditional magnesium alloy continuous casting and rolling process are effectively solved, meanwhile, the secondary heating link is omitted, and the energy consumption and the production cost are remarkably reduced. The continuous and efficient production of the magnesium alloy plate can be realized, and the obtained product has the advantages of fine grains, uniform structure and the like, is suitable for processing and manufacturing of a plurality of series of magnesium alloys such as AZ, MB and the like, and has a good industrial application prospect.