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

A manufacturing engineering of a large power low speed diesel engine bush belongs to the manufacturing technical field of the large-scale machinery bush. The invention makes the bush manufacturing according to the processing sequence: from the blank manufacturing, blank casting surface deal (blasting process and cleaning), hot dip coating, casting babbit, finish machining to final inspection. The invention has the characteristic of simple manufacture, high product intensity, good quality, high reliability, low cost etc., so the products has even fine texture, high bond strength of the alloy layer, which can satisfy the working request of the large power low speed diesel engine bush. The invention can be widely used in the large-scale heavy duty machinery, specially for the boat large power low speed diesel engine.

The invention discloses a processing technology of a robot RV speed reducer needle gear shell, and belongs to the technical field of robot RV speed reducer processing. The processing technology includes the steps that precise casting or forging is carried out on a needle gear shell blank; the needle gear shell blank is clamped after the surface of the needle gear shell blank is machined, and the rotation center of the needle gear shell blank is taken as a positioning reference; the end face of the needle gear shell blank, a bearing position of a roller pin bearing and bearing positions of two main bearings are machined; finish machining is carried out on the inner surface of the roller pin bearing according to the positioning reference; finish machining is carried out on a roller pin groove in line contact with a roller pin of the roller pin bearing according to the positioning reference; inner grooves are simultaneously machined in the bearing positions of the two main bearings in a finish machining mode according to the positioning reference; finish machining is carried out on the outer surface of the needle gear blank. The needle gear shell machined according to the steps improves machining precision and the parallelism degree of the bearing positions of the main bearings, guarantees coaxiality, the position degree and cylindricity of the main bearings after installation, achieves one-time clamping, can meet requirements of multiple process parameters, improves machining precision and installation precision of the needle gear shell, reduces accumulated errors, meets the high-precision requirements, and prolongs service life.

The invention relates to a preparation method of an enhanced magnesium alloy-based neutron absorption plate. The method comprises the following steps: aiming at the actual condition of nuclear radiation protection, with boron carbide powder, boron powder, magnesium powder and aluminum alloy powder as raw materials, adopting a vacuum hot-pressing technique under the assisted action of an electric field, and preparing a magnesium alloy-based neutron absorption plate blank under electric field heating, resistance heating, pressurizing and vacuum conditions, so that B4C particles and B particles are evenly distributed in a matrix; oxidation of the material is effectively prevented by the vacuum environment; the interface bonding intensity is improved by the electric field action; the blank is molded in a hot extrusion manner; the particle distribution uniformity is improved; the plastic deformation property of the material is improved; the extruded blank is subjected to hot rolling to obtain the plate; the internal metallographic structure of the material is relatively dense; the preparation method is advanced in process, and accurate, detailed and accurate in data; the neutron absorption property of the magnesium alloy-based neutron absorption plate reaches 98%; the material density reaches 99%; the material hardness reaches HV0.1=186.7; the particle distribution is uniform; and the enhanced magnesium alloy-based neutron absorption plate is a lightweight and high-strength composite plate with good neutron absorption property.

Provided is a method for manufacturing a starting ratchet wheel of a motorcycle. Metal powder serves as a raw material and is sintered after compression forming in a mould. The method is characterized in that pressure for compression is 80-115 tons, and dwell pressure for demoulding is 9-15 tons. The metal powder serves as the raw material, is alloyed into alloy steel by compressing and sintering, and is completely free of mechanical cutting, and accordingly waste of steel materials is avoided, steel resource is greatly saved, and the produced starting ratchet wheel of the motorcycle has mechanical performance of the alloy steel, the mechanical performance and overall quality of the starting ratchet wheel are further improved, and production efficiency is also greatly increased. The method is simple in production process, the starting ratchet wheel is high in precision and fine in consistency, and stability of quality of products in mass production is guaranteed.

The invention relates to a manufacturing process of a bearing bush of a high-power low-speed diesel engine, which belongs to the technical field of manufacturing bearing bushes of large mechanical equipment. In the invention, the bearing bush is manufactured according to the technological sequence of: rough blank manufacturing → blank pouring surface treatment (shot blasting treatment and cleaning) → tin enamel → casting babbitt alloy → finishing machining and final inspection. Because the method of the present invention has the characteristics of simple manufacture, high product strength, good quality, high reliability, and low production cost, the product manufactured by the process of the present invention has a uniform metallographic structure, high bonding strength of the alloy layer, and can meet large Therefore, the bearing bush manufactured by the present invention can be widely used in large-scale heavy-duty mechanical equipment, and is especially suitable for marine high-power low-speed diesel engines.

The invention relates to a coating hot-pressing reinforcement method of a magnesium-aluminum alloy plate. According to the coating hot-pressing reinforcement method, aiming at the situations of soft texture, low hardness and strength and poor corrosion resistance of the magnesium-aluminum alloy plate, a layer of magnesium-aluminum-erbium alloy coating is formed on the magnesium-aluminum alloy plate through hot-pressing sintering by taking rare earth erbium as a reinforcing agent and using the steps of casting of magnesium-aluminum-erbium alloy, powder forming through ball milling, hot-pressing sintering and low-temperature tempering, wherein firm bonding between the coating and the alloy plate is achieved, therefore strength, hardness and corrosion resistance of the magnesium-aluminum alloy plate are greatly increased, coating hardness reaches 270HV which is increased by 3.55 times, and corrosion resistance of the magnesium-aluminum alloy plate with the magnesium-aluminum-erbium alloy coating is increased by 519 percent compared with that of the magnesium-aluminum alloy plate without the magnesium-aluminum-erbium alloy coating. The preparation method disclosed by the invention has the advantages of advanced process, detailed and accurate magnitude, good coating bonding force, compact metallographical tissues and capability of being applied in multiple industrial fields and is the very ideal coating hot-pressing sintering reinforcement of the magnesium-aluminum alloy plate.