45results about How to "Refine matrix tissue" patented technology

The invention discloses a liquid-state near-net forming method and device for a continuous carbon fiber enhanced aluminum-based composite material, namely a vacuum-assisted pressure-adjusting and infiltration casting method and device. The method comprises four procedures of smelting an alloy and pre-heating fibers, carrying out vacuum-assisted pressure-adjusting and infiltration, condensing at a high pressure and cooling rapidly. The device is composed of an alloy smelting device, a vacuum-assisted pressure-adjusting and infiltration device and a casting rapid cooling device. The liquid-state near-net forming method and device have the characteristics that (1) low-oxygen and temperature-controllable pre-heating of nickel-plated carbon fibers is realized; (2) low-pressure infiltration and high-pressure condensation of the aluminum-based composite material are realized; (3) the control of a cooling speed in the condensation of a composite material casting is realized. According to the liquid-state near-net forming method and device for the continuous carbon fiber enhanced aluminum-based composite material, oxidization and burning loss caused by pre-heating the carbon fibers, prefabricated body deformation in the infiltration process and interface reaction problems in the condensation process of the composite material are solved. The liquid-state near-net forming of the continuous carbon fiber enhanced aluminum-based composite material can be realized and the prepared composite material has the advantages of dense tissues, few interface reactions, high mechanical properties and the like.

The invention discloses an isothermal superplastic deformation method for a micro / nano particulate reinforced titanium matrix composite. The method comprises the following steps of A, preparing a titanium boride and rare earth oxide micro / nano particulate hybrid reinforced titanium matrix composite by utilizing an in-situ synthesis technique, and performing vacuum consumable electrode arc melting on the composite for more than two times; B, performing cogging forging on the composite in a Beta single-phase region, wherein deformation amount is greater than or equal to 50 %; performing isothermal forging on the composite in an (Alpha + Beta) two-phase region to obtain a titanium matrix composite forging blank, wherein deformation amount is greater than or equal to 60 %; and C, performing hot rolling on the titanium matrix composite forging blank in a near Beta phase region, wherein deformation amount is greater than or equal to 80 %, and performing annealing treatment to obtain the micro / nano particulate reinforced titanium matrix composite. The micro / nano particulate reinforced titanium matrix composite is formed by the isothermal forging technology and hot rolling, and thus, the matrix structure can be effectively refined, and the material forming rate is increased; and a plate has good superplasticity within the deformation process range of 800-1000 DEG C and 5 x 10<-3>-10<-4>s<-1>.

The invention discloses a preparation method of a high-accuracy magnesium alloy plate. The preparation method of the high-accuracy magnesium alloy plate comprises the steps of composition of raw materials, processing of the raw materials, smelting, cooling, machining in a pressurization mode and the like. The magnesium alloy plate prepared through the preparation method is good in corrosion resistance, largely improves physicochemical parameters such as breaking strength and ductility, has good market application value, and can be applied to the fields of automobile gearboxes and engine cases.

The invention relates to the technical field of structure refinement and homogenization of bearing steel, in particular to high-carbon bearing steel and a preparation method thereof. The high-carbon bearing steel comprises the following chemical components: 0.80-1.20 wt% of C, 0.40-2.0 wt% of Cr, 0.15-0.75 wt% of Mn, 0.15-0.75 wt% of Si, 0-0.20 wt% of Nb, 0-0.20 wt% of Mo, 0-0.20 wt% of V, less than or equal to 0.015 wt% of P, less than or equal to 0.01 wt% of S and the balance of Fe and inevitable impurities, wherein the contents of Nb, Mo and V are not 0 at the same time. The microalloying elements Nb, Mo and V are added into the high-carbon bearing steel and are matched with other element components, so that the matrix structure of the bearing steel can be effectively refined, a large amount of nano carbide is promoted to be separated out, and the contact fatigue life of the high-carbon bearing steel is further prolonged.

The invention discloses a production process of a QT500-12 spheroidal graphite iron casting. The production process comprises the following steps: A, raw material selection: selecting 60-80 parts of scrap steel, 20-40 parts of scrap returns, 2.5-3.5 parts of a carburant, 0.4-1.0 part of 75# ferrosilicon, 0.3-0.6 part of copper, 1-1.2 parts of a spheroidizing agent, 0.8-1.2 parts of a 75# ferrosilicon inoculant and 0.2-0.4 part of a silicon-strontium inoculant; B, weighing; C, smelting; D, spheroidizing; E, secondary inoculation; and F, pouring. The overall performances of the QT500-12 spheroidal graphite iron casting produced by using the production process are improved, and the tensile strength is larger than or equal to 500Mpa on the premise that the elongation percentage is larger than or equal to 12%; the consistency of a matrix structure of the spheroidal graphite iron casting is also realized, and the local function of the spheroidal graphite iron casting is prevented from being deteriorated; and the weight of the spheroidal graphite iron casting is reduced on the premise that the elongation percentage and tensile strength indexes of the spheroidal graphite iron casting reach standards, so that the lightweight of the spheroidal graphite iron casting is realized.

The present invention discloses compound high speed steel roll and its making process. The compound high speed steel roll consists of roll body and roll core compounded through central casting. The roll body is made of high speed steel comprising chemically C 1.8-2.8 (in wt%, same as below), Mo 4.0-8.0, V 3.0-7.0, Nb 1.5-4.0, Cr 6.0-12.0, RE 0.1-0.25, Ti 0.15-0.40, N 0.08-0.20, K 0.06-0.18, Si<2.0, Mn<2.0, S<0.05 and P<0.05, except Fe and inevitable impurity. The roll core is made of high strength nodular cast iron comprising chemically C 3.2-3.6 (in wt%, same as below), Si 1.8-2.4, Mn 0.4-0.8, Ni 0.3-1.2, Cr 0.3-0.8, Mo 0.2-0.5, Mg 0.03-0.08, RE 0.05-0.14, P<0.08 and S<0.03, except Fe and inevitable impurity. The compound high speed steel roll has high wear resistance, simple making process and high production efficiency.

The invention discloses a microalloyed high-strength high-plasticity non-magnetic steel plate. The non-magnetic steel plate comprises the following chemical elements by mass: 0.10 to 0.20% of C, morethan 0 and no more than 0.4% of Si, 20 to 26% of Mn, 2.0 to 3.0% of Al, 0.01 to 0.02% of Ti and 0.04 to 0.09% of Nb, with the balance being Fe and unavoidable impurities. The matrix structure of the non-magnetic steel plate is fine deformed austenite crystal grains. Accordingly, the invention also discloses a manufacturing method for the non-magnetic steel plate. The manufacturing method comprisesthe following steps: (1) smelting and casting; (2) heating, wherein a heating temperature is 1120 to 1170 DEG C; (3) rolling; and (4) cooling after rolling. The non-magnetic steel plate of the invention adopts a microalloying design, so the non-magnetic steel plate has high strength and good plasticity, with yield strength being 450-510 MPa and tensile strength being 660-710 MPa.

The invention discloses a method for producing nodular cast iron from low-manganese steel scrap accessories. The method comprises the steps as follows: low-manganese steel scrap, recirculated iron andadditives are matched in percentage by weight, and the additives include a nodulizer, 75SiFe and a carburant and are added as per the percentage of the total weight of the low-manganese steel scrap and the recirculated iron; the recirculated iron, the carburant and the low-manganese steel scrap are sequentially added to an electric medium-frequency induction furnace, heating is stopped after thetemperature rises to 1,500-1,530 DEG C, and slag is cleaned through raking; the nodulizer and 75SiFe are sequentially placed into a nodulizing ladle reaction chamber, and the chamber is covered with an upper cover; the molten iron discharging temperature is controlled to be 1,520+ / -10 DEG C, molten iron in the electric furnace is poured into the nodulizing ladle reaction chamber from a liquid inlet in the upper cover, and the nodulizing reaction time is controlled to range from 60 s to 120 s; the pouring temperature is controlled to range from 1,390 DEG C to 1,410 DEG C, and pouring is performed in a manufactured sand mold cavity. The method has the beneficial effects as follows: produced castings have the good density; the method is convenient to operate and master; the production cost can be reduced; the low-manganese steel scrap has the stable source and is convenient to buy, resources can be saved, and the energy consumption can be reduced.

The invention discloses an isothermal superplastic deformation method for a micro / nano particulate reinforced titanium matrix composite. The method comprises the following steps of A, preparing a titanium boride and rare earth oxide micro / nano particulate hybrid reinforced titanium matrix composite by utilizing an in-situ synthesis technique, and performing vacuum consumable electrode arc melting on the composite for more than two times; B, performing cogging forging on the composite in a Beta single-phase region, wherein deformation amount is greater than or equal to 50 %; performing isothermal forging on the composite in an (Alpha + Beta) two-phase region to obtain a titanium matrix composite forging blank, wherein deformation amount is greater than or equal to 60 %; and C, performing hot rolling on the titanium matrix composite forging blank in a near Beta phase region, wherein deformation amount is greater than or equal to 80 %, and performing annealing treatment to obtain the micro / nano particulate reinforced titanium matrix composite. The micro / nano particulate reinforced titanium matrix composite is formed by the isothermal forging technology and hot rolling, and thus, the matrix structure can be effectively refined, and the material forming rate is increased; and a plate has good superplasticity within the deformation process range of 800-1000 DEG C and 5 x 10<-3>-10<-4>s<-1>.

The invention belongs to the technical field of metal matrix composite materials and preparation thereof, and particularly relates to a preparation method for reinforcing a Ti2AlNb composite materialby using graphene. The preparation method adopts the graphene to reinforce a Ti2AlNb alloy, optimizes the properties of the Ti2AlNb alloy, and adopts the graphene to reinforce the Ti2AlNb composite material prepared by spark plasma sintering, it is found that the graphene is evenly distributed in the composite material, the relative density of the composite material reaches 98% or above, and whenthe content of the graphene is 0.5 wt.%, the fracture toughness and elongation of the composite material are improved by 70% and 51% correspondingly; the preparation method fully shows that the graphene has very remarkable toughening and plasticizing effects on the Ti2AlNb alloy, and when the the Ti2AlNb alloy is applied to the field of aviation starting, the combat performance of an aircraft canbe greatly improved.

The invention discloses a production method of a steel wear-resistant plate BTW for coal mines. The production method comprises the steps of steel ingot billeting, billet heating, high-pressure water dephosphorization, rolling, cooling and straightening. The invention controls the heating curve, optimizes the design of the rolling schedule, and controls the rapid cooling after rolling to obtain the steel wear-resistant plate BTW for coal mines with good surface quality, and the strength and wear resistance meet the requirements of users, and is widely used in the field of coal mines. The BTW thickness specification of the steel wear-resistant plate for coal mine obtained in the present invention is 15-50mm, and after the use performance is agreed with the user: the guaranteed tensile strength is ≥700MPa, the yield strength is 400-480MPa, and the impact energy is ≥80J; the wear-resistant plate BTW has a flat shape, Flatness ≤ 5mm / 1m, surface quality meets the requirements of GB / T14977 Class B, steel plate delivery without grinding.

The invention relates to a method for preparing acicular second phases to improve the degradation resistance of medical magnesium alloys. The magnesium alloy includes an AZ61 matrix and acicular Al uniformly distributed in the matrix 4 Ce phase. Its preparation method is as follows: ball milling Ce powder and AZ61 powder to obtain mixed powder, and then preparing acicular Al-containing powder by SLM 4 Ce phase magnesium alloy. On the one hand, the present invention can significantly refine matrix grains and acicular Al 4 The Ce phase structure, on the other hand, increases the solid solubility of solute elements and inhibits Mg 17 Al 12 Precipitation of the second phase. Acicular Al 4 The Ce phase has both a smaller potential difference and a larger resistance to the matrix, which can inhibit galvanic corrosion; and the Al 4 The Al in the alloy is consumed during the formation of Ce, which can also reduce and refine the original Mg in the alloy 17 Al 12 Phase, thereby reducing galvanic corrosion, the two work together to improve the degradation resistance of magnesium alloys, thereby promoting its application in degradable implants.

The invention discloses a high-current and high-power maintenance-free slip ring. The high-current and high-power maintenance-free slip ring comprises a mounting plate, wherein a bearing pedestal is arranged on the top surface of the mounting plate; an inner ring of the bearing pedestal is connected with the slip ring; a stand column I is arranged on the top surface of the slip ring; the top end of the stand column I is connected with a rotating ring; the stand column I is provided with conductive rings; an outer ring of the bearing pedestal is connected with a stand column II; the top end of the stand column II is connected with a protective cover; the stand column II is provided with electric brushes with conductive columns; the conductive columns are elastically connected with the corresponding electric brushes through springs; the conductive columns are connected with the corresponding conductive rings in a fitting manner; a dust holding groove is formed in the connecting place between the stand column II and the outer ring of the bearing pedestal; and the corresponding fitting places between the conductive columns and the conductive rings are vertically corresponding to the dust holding groove. The stand column I is driven by a shifting fork to rotate so as to enable the conductive rings and the corresponding conductive columns on the electric brushes to be in friction constantly to realize electric connection; powder generated in the friction can naturally fall into the dust holding groove without being cleaned, so that the maintenance-free effect is realized; and in addition, the cost is effectively lowered while the reliability is high.

The invention belongs to the field of machining of alloy materials and discloses an aluminum alloy pressure-cast door plank. The aluminum alloy pressure-cast door plank is prepared from the following raw materials in percentage by weight: 4.1%-4.3% of magnesium, 1.8%-2.1% of manganese, 0.8%-0.9% of zinc, 0.6%-0.7% of copper, 0.3%-0.4% of nickel, 0.1%-0.2% of white graphite, 0.04-0.05% of cerium, 0.04%-0.05% of yttrium, 0.02%-0.03% of samarium, 0.01%-0.02% of silicon dioxide and the balance of aluminum. The aluminum alloy pressure-cast door plank is high in mechanical strength, can resist corrosion and is unlikely to be oxidized and change color; the preparation method is simple, feasible and suitable for large-scale production.

The invention relates to a smelting method of high-toughness and high-strength casting-state ductile cast iron. The smelting method comprises the steps of 1, material selection, in which pig iron, scrap steel and a melting-back material are selected as raw materials; 2, material preparation, in which 20-40% of pig iron, 30-40% of scrap steel and 20-50% of melting-back material are selected according to percent by mass; 3, smelting, in which the raw materials prepared in the step 2 are added into a medium-frequency smelting furnace, the temperature is raised, the raw materials are molten, a carburant is added to the bottom of the furnace during smelting, and the raw materials are molten to a required furnace outlet temperature; 4, nodulization and casting, in which a nodulization pack and acasting pack are pre-heated to 600-800 DEG C before nodulization, a nodulizing agent, an inoculation agent and a coverage agent are sequentially placed in the nodulization pack placement pit, and inoculation for three times is performed; and 5, box outlet. The smelting method is simple to operate; and by adding the scrap steel and the melting-back material in a large proportion, the production cost is low, and the mechanical property is improved by a reasonable proportion.