34results about How to "Improve nitriding effect" patented technology

A steel piston ring and a steel cylinder liner are described which comprise as the main body a steel composition which has good nitridability. The steel composition consists of the following elements: 0-0.5 weight % B, 0.5-1.2 weight % C, 4.0-20.0 weight % Cr, 0-2.0 weight % Cu, 45.30-91.25 weight % Fe, 0.1-3.0 weight % Mn, 0.1-3.0 weight % Mo, 0-0.05 weight % Nb, 2.0-12.0 weight % Ni, 0-0.1 weight % P, 0-0.05 weight % Pb, 0-0.05 weight % S, 2.0-10.0 weight % Si, 0-0.05 weight % Sn, 0.05-2.0 weight % V, 0-0.2 weight % Ti and 0-0.5 weight % W. The steel piston ring and the steel cylinder liner can be manufactured in a casting process using the machinery and technology employed for the manufacture of cast iron parts.

The invention discloses a two-segment protection air hole type atmosphere supersonic plasma spraying device. The two-segment protection air hole type atmosphere supersonic plasma spraying device is characterized by further comprising an anode sprayer; the front end of the anode sprayer is cylindrical; a center through hole is formed; the anode sprayer is further provided with protection air holes and powder conveying holes; the inlet ends of the protection air holes are arranged on the cylindrical face of the anode sprayer; the outlet segments of the protection air holes are arranged on the front end face of the anode sprayer; the protection air holes comprise the first-segment air hole and the second-segment air hole; the axis of the first-segment air hole and the axis of the center through hole form an acute angle alpha; the axis of the second-segment air hole is parallel with the axis of the center through hole; the inlet ends of the powder conveying holes are arranged on the cylindrical face of the anode sprayer; the outlet ends of the powder conveying holes are communicated with the center through hole; and the axis of each powder conveying hole is perpendicular to the axis of the center through hole. The two-segment protection air hole type atmosphere supersonic plasma spraying device is simple in structure and not provided with a solid cover, it is not needed to additionally install a water cooling device, installing, dismantling and checking are convenient, the jet flow temperature and the particle spraying temperature can be lowered, and the particle spraying oxidization possibility is reduced.

The invention discloses a process for nitriding a metal surface, which includes a metal workpiece to be processed, and the processing of the workpiece includes the following steps: soaking the workpiece with water containing detergent, rinsing with clean water and immersing it in 100°C water Wash the workpiece; place the degreased workpiece in the pool for ultrasonic cleaning, the cleaning vibration frequency is 80-160KHz, and the power density is set at 0.6-1.0W / C; preheat the workpiece to 300-385°C, and the preheating time 6‑25min; place the workpiece in a nitriding furnace with base salt containing Li ions, raise the nitriding furnace to 520‑580°C, and nitriding time is 80‑100min; add sodium peroxide solid to the base salt , and the weight ratio of solid sodium peroxide to the weight ratio of the base salt is 1:2.5-4.5. In the present invention, by adding ultrasonic cleaning, it can quickly realize a strong cleaning effect on the workpiece during the cleaning process of the workpiece, so that the solid dirt on the surface of the workpiece is separated from the workpiece, so that it can effectively clean the workpiece during the nitriding process. Improve the effect of nitriding.

The invention relates to the technical field of metallurgy and provides a preparation method of a VN19 vanadium nitrogen alloy. The invention mixes powdery vanadium oxide, silicon dioxide powder, carbonaceous reducing agent, iron powder and binder, and then carries out ball pressing, drying, vacuum carbonization reduction and nitriding in sequence to obtain VN19 vanadium nitrogen alloy. In the present invention, silicon dioxide powder is added to the raw material, and the silicon dioxide powder is reduced to form silicon nitride during the nitriding process, which is beneficial to increase the nitrogen content of the product. The present invention carries out carbonization reduction under vacuum conditions, and carries out nitriding under high nitrogen pressure, and can realize energy-saving, high-efficiency and fast preparation of VN19 vanadium-nitrogen alloy. Furthermore, the present invention optimizes the direction of the nitrogen gas flow during the nitriding process, and adopts weak cooling and strong cooling in the cooling process in sections to increase the nitrogen content of the product, make full use of heat energy, and reduce the production cost.

The invention discloses an atmospheric supersonic plasma spraying device for forming a protective gas hood, which comprises an anode nozzle, which is in the shape of a revolving body and has a central through hole. On the circumferential surface of the anode nozzle, the outlet end communicates with the central through hole, and the axis of the protective air hole forms an acute angle α with the axis of the central through hole; the inlet end of the powder feeding hole is set on the circumferential surface of the anode nozzle, and the outlet end is connected to the axis of the central through hole. The central through hole is communicated, and the axis of the powder feeding hole is perpendicular to the axis of the central through hole. The invention has simple structure, no solid cover, no need to install a cold water device, convenient installation, disassembly and inspection, and the spraying material is not easy to adhere to the nozzle hole. The oxidation of the sprayed particles in the middle, and has a certain cooling effect on the jet, so as to reduce the temperature of the jet and the temperature of the sprayed particles, and reduce the possibility of oxidation of the sprayed particles.

The invention provides a modified nickel-cobalt lithium manganate ternary positive electrode material, a preparation method and application thereof. The preparation method of the modified nickel-cobalt lithium manganese oxide ternary positive electrode material includes the following steps: preparing a braided spherical nickel-cobalt lithium manganate ternary material; mixing the nickel-cobalt lithium manganate ternary material powder with rare earth The nitride and lithium nitrogen mixture is subjected to the first ball milling and mixing treatment to obtain the mixture powder; and the mixture powder is subjected to segmental sintering treatment under a nitrogen-oxygen mixed atmosphere. The preparation method of the modified nickel-cobalt lithium manganese oxide ternary positive electrode material uses a mixture of rare earth nitride and lithium nitrogen to coat the ternary material particles, which effectively improves the capacity and cycle retention of the ternary material, and improves the performance of the ternary material. The nitriding effect can better alleviate the mixed lithium and nickel of the material and the excess lithium on the surface of the material; at the same time, the nitride coating layer reduces and prevents the contact between the electrolyte and the active material, reduces irreversible side reactions, and reduces the solid electrolyte membrane (SEI )Formation.

The invention discloses an atmosphere supersonic speed plasma spraying device with two-section type protection air holes. The spraying device comprises an anode nozzle. The front end of the anode nozzle is cylindrical, and a center through hole is formed in the anode nozzle. The anode nozzle is further provided with the protection air holes and powder feeding holes. The inlet ends of the protection air holes are arranged on the circumferential face of the anode nozzle, and the outlet sections of the protection air holes are arranged on the front end face of the anode nozzle. The protection air holes comprise the first section of air holes and the second section of air holes. The axis of the first section of air holes and the axis of the center through hole form an acute angle of alpha, and the axis of the second section of air holes and the axis of the center through hole form an acute angle of beta. The inlet ends of the powder feeding holes are arranged on the circumferential face of the anode nozzle, and the outlet ends of the powder feeding holes communicate with the center through hole. In addition, the axis of the powder feeding holes is perpendicular to the axis of the center through hole. The atmosphere supersonic speed plasma spraying device is simple in structure, a solid cover is omitted, and additional arrangement of a cold water device is needless. Mounting, dismounting and inspection are convenient, the temperature of jet flow and the temperature of spraying particles can be lowered, and oxidization probability of the spraying particles is reduced.

The invention discloses a method for preparing a samarium ferronitrogen magnet with high coercivity by a nitrogen rare earth complex, belonging to the technical field of magnetic materials. The Sm2Fe17Nx nanocrystalline thin ribbon is immersed in a mixed solution of nitrogen rare earth complex and absolute ethanol, The addition of nitrogen-based rare earth complexes can further enhance the nitriding effect of SmFeN magnets, thus effectively enhancing the magneto-crystalline anisotropy and coercivity of the main phase. The invention has the advantages of simple process, easy operation, low cost, and is favorable for the application of samarium ferronitrogen magnetic powder with high coercivity in more permanent magnetic devices to meet the market demand.

The invention discloses a medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method. The medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method comprises the following steps of putting a medium and low-carbon alloy constructional steel workpiece into a solid solution nitrogenation furnace which is shown in the patent having a patent name of pressurization high-temperature nitridation device with dual pressure equilibrium structure and having the patent number of 201210530358.6, improving the pressure to 0.1-0.5MPa at a temperature of 500-800 DEG C, feeding NH3 into the solid solution nitrogenation furnace at a flow rate of 0.1-0.5L / min, carrying out gas nitridation treatment at a decomposition rate of 30-80% for 5-20 hours, sequentially feeding NH3 into the solid solution nitrogenation furnace, cooling to a temperature below 150 DEG C, and taking out the workpiece. The medium and low-carbon alloy constructional steel surface pressurization gas-nitridation method can effectively promote adsorption of N atoms on the part surface, improve N activity, an interface reaction rate and a hole and slit nitridation capability, reduce an NH3 decomposition rate, improve nitrogen potential, obviously reduce an NH3 consumption amount in nitridation, greatly improve process effects and realize short-term deep nitridation.

The invention relates to the field of valve nitridation, in particular to a nitridation device and process based on valve high stability. The nitridation device based on the valve high stability comprises a first conveyor belt, a polishing mechanism, a machine frame, a gas storage tank, a drying stove and a reactor, wherein the gas storage tank, the drying stove and the reactor are sequentially arranged on the machine frame. The nitridation process based on the valve high stability includes the following steps that firstly, a valve is sent into the drying stove through the first conveyor beltto be baked, and nitrogen is heated at the same time; secondly, when the valve is baked to 290 DEG C to 310 DEG C and the nitrogen is heated to 390 DEG C to 410 DEG C, the valve and the nitrogen are sent into the reactor to be subjected to nitridation treatment; thirdly, after nitridation treatment is conducted for 35 min to 45 min, the valve is sent onto a second conveyor belt; and fourthly, thevalve is polished through the polishing mechanism. When the technical scheme is adopted, dark dirt on the surface of the valve can be removed while the stability of the valve is improved.

The invention discloses a dental plate surface nitriding technology, and relates to the technical field of workpiece nitriding treatment. The technology comprises the steps of 1) preparing before treatment, 2) vacuumizing, 3) heating, 4) reheating, 5) vacuumizing, 6) surface activating, 7) vacuumizing, 8) decomposing through ammonia gas, 9) nitriding, 10) vacuumizing, 11) blackening, and 12) cooling. The technology has the beneficial effects that the fatigue resistance of a workpiece is improved; high pressure stress is generated in a nitriding layer, so that the fatigue limit of the workpieceis high, and the sensitivity of the workpiece is low under the effect of alternating load; and moreover, the fatigue limit of the workpiece subjected to alternating load can be increased by 200%.

The invention discloses a magnesium smelting technique by microwave heating and relates to the field of magnesium smelting techniques. The upper end of the round wall of a furnace body is connected with an expander by bricklaying through a refractory material, and the lower end of the round wall of the furnace body is fixed with a tray; the expander is movably connected with a support in a sliding manner; the lower end of a microporous ceramic tube is fixed with the tray while the upper end of the microporous ceramic tube is fixed with the support; the furnace body is fixed with a microwave generator and a shell; the shell is fixed with an upper flange and a lower flange; a gaseous magnesium collecting chamber is formed by the wall of the furnace body above the support, an upper convergent section of the shell and the inner side of the upper flange; a gaseous magnesium outlet tube is penetrated from the gaseous magnesium collecting chamber and then is fixed with the furnace body and the shell; a slag chamber is formed by the wall of the furnace body below the tray, a lower convergent section of the shell and the inner side of the lower flange; a magnesium ball is put in the microporous ceramic tube; slag is put in the slag chamber; the power of the microwave generator is 1-500KW, the frequency of the microwave generator is 300-3000MHz, the temperature of the microwave generator is 1200-1350 DEG C, and the smelting time is 15-60 minutes; the magnesium ball is acquired by roasting dolomite to acquire magnesium oxide and calcium oxide and then mixing silicon iron and fluorite with magnesium oxide and calcium oxide. The magnesium smelting technique by microwave heating is used for smelting magnesium, which is a microwave new energy heating technology.