44results about How to "Dense metallographic structure" patented technology

A method for repairing a lubricant pump shell bushing by plasma sprayed Cu-Al coating belongs to the technical field of aviation. The repairing of a narrow-arc convex end face of the lubricant pump shell bushing by a plasma spraying method comprises the steps of washing, grit blasting, protection, spraying the spray material on the narrow-arc convex end face of the lubricant pump shell bushing by plasma spraying equipment. By adopting the method for repairing the lubricant pump shell bushing by plasma sprayed Cu-Al coating, the sprayed coating has as high as 41.07MPa of bonding strength and relatively stable hardness value. Bending test result shows that the coating bond is relatively good, and coating microscopic test shows that the metallurgical structure is relatively compact. The method has the advantages of reasonable process and correct preferences, which achieves the effect of repairing the lubricant pump shell bushing and has significance in prolonging the service life of the lubricant pump shell bushing and reducing economic loss.

The invention discloses an integrated machining method of a planet carrier of a robot RV reducer, and belongs to the technical field of robot RV reducer machining. The method comprises the steps as follows: forging a first casing and a second casing, and performing hot extrusion on the first casing and the second casing respectively; performing thermal refining; performing tempering; performing finish machining on end surfaces respectively; connecting the first casing with the second casing to be clamped to a clamp, and performing finish machining on inner holes formed in the first casing and the second casing with a center of gyration serving as a locating basis; performing finish machining on outer surface with the locating basis; directly machining inner rings of rolling bearings on the first casing and the second casing; accurately grinding an outer track on each inner ring simultaneously; and performing finish machining bearing positions of three tapered roller bearings on the first casing and the second casing with the location reference, and directly machining outer rings of the tapered roller bearings. With the adoption of the method, the mounting accuracy, the manufacturing accuracy and the transmission accuracy are ensured, the requirement for high accuracy is met, the service life is prolonged, machining and assembling errors and accumulative errors are reduced, the output torque is increased, and the machining cost is effectively reduced.

The invention relates to a smelting degassing method of aluminum-silicon alloy liquid. Aiming at the actual condition that gas and impurities exist in the aluminum-silicon alloy liquid in the smelting course, a method of smelting direct-current electric field purification and circulation degassing outside a furnace is adopted to remove 99.5% of main gas, i.e. hydrogen, from the aluminum-silicon alloy liquid, so that an aluminum-silicon alloy having a compact metallographic structure can be obtained, and the aluminum-silicon alloy has no bubble or shrinkage cavity and is not subject to shrinkage porosity. The method has the advantages of advanced and reasonable process, continuous step, environment protection and energy conversation, the properties of aluminum-silicon products are greatly enhanced, the tensile strength can be enhanced by 91%, and the method is an ideal degassing method of aluminum-silicon alloy liquid.

The invention discloses a zinc-aluminum-nickel alloy co-penetrated protective layer preparation method, which comprises the following steps of weighing co-penetrated agent raw materials: zinc powder, aluminum powder, alumina powder, nickel powder, rare-earth metal oxide powder and catalyst; uniformly mixing the weighed powder, heating the mixture to be 150 to 200 DEG C, insulating for 30 min to 50 min, cooling to be room temperature, and then uniformly mixing with the catalyst to prepare a co-penetrated agent; stacking bridge embedded parts plates with smooth and clean surfaces to form a stack with approximate height and width, paving a layer of co-penetrated agent between each two adjacent bridge embedded part plates, then packaging to form bundles, placing the bundles into a co-penetrated furnace, adding the co-penetrated agent, heating to be 400 to 500 DEG C, and carrying out co-penetrated treatment for 2 h to 3 h under the pressure of 0.10 to 0.20 MPa. According to the zinc-aluminum-nickel alloy co-penetrated protective layer preparation method provided by the invention, the space of the co-penetrated furnace can be efficiently utilized; a zinc-aluminum-nickel alloy co-penetrated protective layer is uniform in thickness and compact in metallographic structure, and has excellent resistance to corrosion on high-temperature salt mist gas; and the phenomenon of hydrogen brittleness does not exist.

The invention discloses a zinc-aluminum-nickel alloy co-penetration agent for bridge embedded parts. The raw materials include the following components in parts by mass: 100 parts of zinc powder, 10-20 parts of aluminum powder, 80-100 parts of aluminum oxide powder, and nickel powder 10 to 30 parts, 2 to 10 parts of rare earth metal oxide powder, 0.1 to 2.0 parts of catalyst, the particle size of the above raw materials is 300 mesh; the zinc powder, aluminum powder, alumina powder, nickel powder and rare earth powder in the above raw materials The metal oxide powder is mixed evenly, heated to 150-200°C, kept for 30-50 minutes, cooled to room temperature, and then mixed with the catalyst to prepare the zinc-aluminum-nickel alloy co-penetrating agent. The zinc-aluminum-nickel alloy co-infiltration anti-corrosion protection layer obtained by applying the invention has the advantages of uniform thickness and compact metallographic structure, excellent corrosion resistance to high-temperature salt spray gas, and no hydrogen embrittlement phenomenon.

The invention relates to a method for spraying a Stellite 20 alloy on the surface of a workpiece. The method comprises the following steps that (1), surface treatment is conducted, specifically, the size of a machined workpiece is detected, cleaning is conducted, and sand blasting and roughening are conducted on the surface of the workpiece, so that the roughness Ra of the surface of the workpiece is 10 microns-13 microns; and (2), the surface of the sprayed workpiece is preheated to 70 DEG C-90 DEG C, spraying equipment is adopted for spraying Stellite 20 alloy powder to the surface of the workpiece, and a coating is deposited for multiple times to make the thickness of the coating be 0.25 nm-0.35 mm. By the adoption of the method, the thickness of the coating on the surface of the workpiece is uniform, the binding force between the coating and a base body is good, the porosity of the coating is low, oxide inclusions are few, the abrasion resistance and corrosion resistance of the coating are good, and the technical indexes required by the valve application field can be met, wherein the hardness is larger than or equal to 750 HV0.3, the porosity is smaller than or equal to 1%, the binding force is larger than or equal to 70 MPa, and the oxide content is smaller than or equal to 2%.

The invention discloses a preparation method of an alloy co-penetration Dacromet and closing layer composite coating. The method includes the following steps of weighing a co-penetration agent raw material to be evenly mixed to prepare a co-penetration agent, stacking platy metal sheets with cleaned surfaces to form a stack with high and width approximately the same, laying a layer of co-penetration agent between every two adjacent platy metal sheets, packing the metal sheets into bundles, putting the bundles in a co-penetration furnace, weighing a Dacromet anticorrosion raw material to be evenly mixed and stirred, adjusting pH, putting the platy metal sheets in a coating solution soaking cage, making the platy metal sheets soaked in a Dacromet anticorrosion coating solution, conducting rotary draining, sending the platy metal sheets into an online drying device to be baked, cooling the platy metal sheets to the room temperature, preparing a normal temperature curing agent from tetraethylenepentamine and cashew phenol glycidyl ether, preparing a front pre-mix component and a curing reaction component to be evenly mixed to prepare a closing solution, spraying the closing solution onto the rotating platy metal sheets, making the platy metal sheets enter a tunnel oven to be dried, and then putting the platy metal sheets in the normal temperature for 2-4 h.

The invention discloses a high alloy steel heat-resistant martensitic stainless steel heat treatment device, and relates to the technical field of stainless steel heat treatment. The high alloy steel heat-resistant martensitic stainless steel heat treatment device comprises a box-type gas furnace and a tray, the upper end of the tray is provided with a plurality of lifting lugs, the tray is provided with at least one slot, and the lower end of the tray is connected with a chassis through bolts; a partition plate is arranged in the chassis, and a sand layer is arranged at the upper end of the partition plate; and at least one supporting leg is arranged at the bottom end of the partition plate, penetrates through the chassis in a clearance manner and extends to the outer side of the chassis. The extension type cooling design in the tray is adopted, the device is adopted, uniform cooling is matched with two times of tempering, so that the metallographic structure of martensitic stainless steel is compact, retained austenite is eliminated, stress is further eliminated, the strength of the martensitic stainless steel is not changed, the toughness is improved, meanwhile, the effects of stabilizing and refining grains and homogenizing the structure can be completely achieved, and the obtained mechanical property result and the high-temperature lasting tensile property completely meet the standard requirements.

The invention discloses a gear ring forming process, and relates to the technical field of gear ring forming processes. The gear ring forming process comprises the following steps that S1 blank forming is conducted, specifically, manganese steel alloy is smelted in a medium open furnace to be in a molten state, the manganese steel alloy in the molten state is cast into a gear ring mold, and a gear ring blank ring is formed; S2 quenching and tempering treatment are conducted, specifically, the gear ring blank ring is taken out and conveyed into a heat preservation box through an automatic conveying device for quenching and tempering treatment; and S3 forming is conducted, specifically, the quenched and tempered gear ring blank ring is taken out, and a gear ring body is formed through machining. The gear ring blank ring is cast, then the blank material is transferred into the heat preservation box through the automatic device for heat quenching and tempering, the internal quality of the gear ring blank ring is improved, manual operation is not needed in the transferring process, and the manual labor intensity is reduced.