3459results about "Solid state diffusion coating" patented technology

A hydrogen gas sensor with a substrate and a zinc oxide nanostructured thin film deposited on the substrate, wherein the zinc oxide nanostructured thin film has a lattice structure with a weight ratio of low binding energy O2− ions to medium binding energy oxygen vacancies in a range of 0.1 to 1.0, and a method of fabricating a gas sensor by thermally oxidizing a metal thin film under low oxygen partial pressure. Various combinations of embodiments of the hydrogen gas sensor and the method of fabricating the gas sensor are provided.

The invention provides a hydrogen induced crack resistant 2000MPa grade zinc-based coated steel plate, which comprises a base plate and a coating, the base plate comprises the following components in percentage by weight: 0.32%-0.40% of C, 0.15%-0.45% of Si, 1.30%-2.50% of Mn, less than or equal to 0.02% of P, less than or equal to 0.02% of S, 0.03%-1.80% of Al, 0.02%-0.10% of Nb, 0.02%-0.15% of Ti, 0.002%-0.005% of B, 0.15%-0.60% of Cr, and Fe and other inevitable impurities; and the plating layer comprises the following components in percentage by mass: 0.15%-3.50% of Al and the balance of Zn. The invention further provides a manufacturing method of the hydrogen induced crack resistant 2000 MPa grade zinc-based plated steel plate. The manufacturing method comprises the steps of smelting, casting, hot rolling and hot dipping. The invention further discloses a hot stamping method of the hydrogen induced crack resistant 2000MPa-grade zinc-based coating steel plate. The hot stamping method comprises the steps of steel plate heating, steel plate cooling and hot stamping. According to the hot stamping forming part produced through the method, the tensile strength of the steel plate is larger than 2000 MPa, the yield strength is larger than 1400 MPa, the elongation is larger than 5%, and the delayed fracture resistance is excellent.

The invention relates to the technical field of motor rotors, and discloses a motor rotor and a machining method thereof.The method comprises the steps that hot forging is conducted on an alloy steel base material based on the preset forging and pressing temperature, and multi-layer gradient cutting is conducted on a rotor initial blank; the method comprises the following steps: performing composite deposition treatment on a cylindrical blank based on a magnetic material, placing the magnetic composite blank in a vacuum environment for dynamic heat treatment, performing dynamic balance finishing on the heat treatment blank based on a preset alloy, performing surface strengthening treatment on a balance rotor in a nitrogen atmosphere, and coating the balance rotor subjected to surface strengthening with a preset coating, the motor rotor with the optimized surface is obtained; and dynamic balance trimming is combined with preset alloy characteristics for microstructure regulation and control, and it is ensured that the rotor has excellent operation stability in a high-rotation-speed environment. And finally, surface strengthening treatment is carried out in a nitrogen atmosphere, and a functional coating is used for covering, so that the wear resistance and corrosion resistance of the surface layer are remarkably improved, and the requirements of a motor system on a high-performance rotor under complex working conditions are met.

The invention relates to a modified current collector for a cathode-free metal battery and a preparation method and application thereof.The preparation method comprises the steps that an in-situ modification reaction is conducted on the surface of a copper current collector to obtain a current collector coated with a copper oxide nanometer material, and then selenium is introduced to the surface of the current collector coated with the copper oxide nanometer material through a partial in-situ substitution reaction to obtain the modified current collector coated with the copper oxide nanometer material. The preparation method comprises the following steps: preparing a copper selenide and copper oxide composite modified current collector, performing in-situ lithiation reaction through electrochemical deposition, and partially converting to generate corresponding lithiates, thereby obtaining the modified current collector for the non-anode metal battery. According to the invention, the functional artificial interface layer with lithium affinity, high stability and high ionic conductivity is constructed on the surface of the copper-based current collector in situ, so that the key problems of uneven metal deposition and unstable SEI layer on the surface of the negative electrode current collector in the current research of the metal secondary battery without the negative electrode are solved, the formation of dendritic crystals and the occurrence of side reactions are inhibited, and the service life of the metal secondary battery is prolonged. Therefore, the coulombic efficiency, the safety and the cycle life of the battery are improved.

The present invention belongs to the technical field of metal materials and their processing, and discloses a treatment method for double glow plasma nitriding on the inner wall surface of a titanium alloy round tube, and obtains a TC4 round tube with a nitriding layer on the inner wall, which significantly improves the hardness and wear resistance of the inner wall of the TC4 titanium alloy round tube, prolongs the service life of the parts, and meets the urgent needs of modern industry for high wear-resistant parts. After cleaning, drying, vacuuming, double glow plasma nitriding, furnace cooling, and precise control of parameters such as heating rate, gas ratio and nitriding time, the thickness and performance of the nitriding layer are precisely controlled, ensuring the stability and repeatability of the treatment effect. The obtained TC4 round tube sample was tested, and the metallographic structure of the nitriding layer on the inner wall was closely combined with the matrix, with a small risk of falling off and a relatively thick layer thickness of up to 17±1µm, and an average hardness of up to 713.04HV, which can reach 2.2 times the hardness of the matrix.

The invention provides an online detection and compensation method for local decarburization of a high-strength spring steel band, which comprises the following steps: arranging an oxygen content sensor in a continuous annealing furnace to monitor oxygen concentration in real time, and marking a potential decarburization risk section; scanning the risk section steel strip by adopting infrared thermal imaging, and generating a carbon distribution map to position a decarburization area; pulse laser heating is conducted on the decarburization area, and methane-argon mixed gas is introduced to achieve in-situ carburization; and finally, local thermal stress is eliminated through high-frequency induction heating. According to the method, decarburization risk dynamic early warning, defect accurate positioning, local efficient carbon supplementation and stress homogenization control are achieved, and the surface quality and fatigue performance of the steel strip are remarkably improved.

The invention relates to the field of nitriding furnaces, in particular to an ammonia gas circulating system of a nitriding furnace, which comprises a furnace body, a furnace cover and a gas inlet mechanism, the furnace body is provided with a containing cavity, the furnace cover is connected to the furnace body and covers a cavity opening of the containing cavity, and the gas inlet mechanism comprises a gas inlet main pipe, an annular pipeline, an electromagnetic valve and a detection assembly, one end of the gas inlet main pipe is connected to the outer wall of the annular pipeline, the other end of the gas inlet main pipe is used for being connected with an external ammonia gas storage mechanism, the electromagnetic valves are connected to the annular pipeline, the other ends of the electromagnetic valves extend into the furnace body, the electromagnetic valves are circumferentially distributed around the axis of the annular pipeline at intervals, and the detection assembly is embedded in the containing cavity to control the electromagnetic valves to be opened and closed. External ammonia gas is conveyed to the annular pipeline through the gas inlet main pipe, then the ammonia gas is input into the furnace body through the multiple electromagnetic valves distributed around the axis of the annular pipeline in the circumferential direction at intervals, meanwhile, the detection assembly controls the electromagnetic valves to be opened and closed through the pressure intensity in the containing cavity, the ammonia gas introduced into the nitriding furnace is evenly distributed to all positions in the nitriding furnace, and the uniform nitriding effect is improved.

The invention discloses an electric engine assembly integral forming process based on precision integral casting, which comprises the following steps: designing a split type precision mold through computer aided design software, and carrying out nitriding treatment to improve the performance; selecting a specific aluminum alloy raw material, performing vacuum induction melting and refining, and injecting the aluminum alloy raw material into a preheated and sprayed mold cavity in a low-pressure casting manner; and demolding after air cooling and water cooling are combined, then after-treatment procedures such as deburring and heat treatment are conducted, and finally detection and assembly are conducted. A conformal cooling water channel design and an ultrasonic-assisted smelting technology are adopted in the process innovation, and the casting process is monitored in real time. According to the process, manufacturing procedures are reduced, compared with a traditional mode, the production efficiency is improved by 30%-50%, the cost is reduced by 20%-30%, the assembling problem is effectively avoided, the sealing performance and reliability of the electric engine are improved, the service life of the electric engine is prolonged, high integration is achieved, and the modern industrial requirement is met.

The invention discloses a tantalum-tungsten alloy surface layer thickness ratio gradient structure coating and a preparation method thereof, and belongs to the technical field of ultrahigh-temperature anti-oxidation coating preparation. A tantalum-tungsten alloy is used as a substrate, and the surface coating of the tantalum-tungsten alloy is prepared through the following steps: (1) solid-phase embedding boronizing; (2) a ZrB2-MoSi2-ZrSi2 layer is prepared through the combination of slurry fusion sintering and a solid infiltration method; and (3) the ZrB2-TaSi2-Zr6Ta2O17 composite coating slurry is prepared in a sintering mode. The total thickness of the prepared coating ranges from 120 micrometers to 200 micrometers, the thicknesses of all the layers are in an exponential gradient relation: tn = t1 * Kn-1 (t0 = 1, K = 1.2-1.3), the problems of uneven thermal stress distribution between the tantalum-tungsten alloy substrate and the coating and between the layers of the coating and ultra-high-temperature anti-oxidation protection of the tantalum-tungsten alloy are successfully solved, the prepared coating is good in binding force and free of defects such as holes and cracks, and the service life of the coating is prolonged. And the tantalum-tungsten alloy can keep a good anti-oxidation effect for a short time under the extreme high-temperature condition of 2000 DEG C.

The invention relates to a preparation method and system for an atomic gas chamber for sapphire coating, and the preparation method comprises the steps: S1, placing a cleaned atomic gas chamber on a heating base station of a reaction chamber, and filling the reaction chamber with replacement gas to discharge residual gas in the reaction chamber; s2, filling aluminum source gas into the reaction chamber, and carrying out chemical adsorption on the wall surface of the atomic gas chamber to form a first film layer; s3, filling replacement gas into the reaction chamber to discharge residual aluminum source gas in the reaction chamber; s4, filling oxide gas into the reaction chamber to oxidize the first film layer and convert the first film layer into an aluminum oxide film layer; s5, filling replacement gas into the reaction chamber to discharge residual oxide gas in the reaction chamber; and S6, repeating the steps S2 to S5 to form a preset number of aluminum oxide film layers with a preset thickness on the wall surface of the atomic gas chamber so as to form the atomic gas chamber with the sapphire coating film. The anti-shielding capability of the alkali metal atomic gas chamber can be enhanced, and the electromagnetic wave precision measurement performance of the atomic gas chamber is improved.

The invention discloses a regulation and control process for a nitridation gradient permeable layer of a die-casting special-shaped die, and belongs to the technical field of die nitridation, and the regulation and control process comprises the following steps: S1, carrying out three-dimensional quantitative analysis on the die to obtain three-dimensional information of the die, and dividing the surface of the die into regulation and control areas of four grades of A, B, C and D; s2, regulation and control area parameter mapping: calling a corresponding basic process parameter set from a preset process parameter mapping table according to different grades of the regulation and control area; s3, mold partition ion nitriding; s2, an ion nitriding furnace with multiple paths of independent control anodes and partitioned gas conveying nozzles is arranged, the mold is placed in the nitriding furnace, the process parameter sets, obtained in the S2, of all the regulation and control areas are distributed to a partitioned gas conveying control system and an anode power supply system to conduct permeation on the mold, and the mold is cooled to the room temperature; the industrial problems that due to the fact that geometrical characteristics of a special-shaped mold are complex, the infiltrated layer thickness is not uniform, and the structure property difference is large are solved, and the infiltrated layer with the enough thickness can be obtained in areas difficult to infiltrate such as deep cavities and narrow slits.

The invention discloses a titanium-aluminum alloy surface high-temperature protection composite coating and a preparation method thereof, and belongs to the technical field of metal material surface modification. The thickness of the composite coating is uniform and controllable within the range of 2-6 microns, the composite coating is composed of three phases of TiSi2, Ti5Si3 and Al2O3, TiSi2 / Ti5Si3 is a continuous phase, and Al2O3 is a dispersed phase; the continuous phase TiSi2 / Ti5Si3 is in contact with and combined with a titanium-aluminum alloy matrix, and the dispersed phase Al2O3 is not in contact with the matrix. The preparation method comprises the steps that the titanium-aluminum alloy is subjected to pretreatment of cutting, polishing and cleaning; embedding into Si powder and SiO2 powder, and carrying out high-temperature diffusion in a vacuum environment. Compared with the prior art, the preparation process is simple and efficient, and the high-temperature protective composite coatings with different thicknesses can be prepared by adjusting the high-temperature treatment time.

The invention relates to the technical field of lamps, in particular to a plating forming process of a lamp. The problems that the interface bonding force of the coating and the matrix is insufficient and the corrosion resistance of the coating is poor are solved. According to the method, micro-arc oxidation is carried out in the pretreatment stage, a compact Al-Si-O ceramic layer is generated on the surface of a high-aluminum matrix in situ, and in combination with deep diffusion of plasma siliconizing, a transition area with gradient Si distribution is constructed; the pitting corrosion resistance of the coating is optimized through the component gradient design of the inner-layer coating, the middle-layer coating and the outer-layer coating; the surface of the coating lamp is subjected to checkerboard scanning by using short pulse laser, so that the porosity and microdefects of the surface of the coating are improved, and the corrosion resistance of the coating is enhanced; a uniform oxynitride passivation film is generated on the surface of the coating in situ through low-temperature plasma post-oxidation-nitridation treatment, the defect that a film layer is easy to strip in a traditional passivation process is avoided, and the corrosion resistance of the material in long-term service can be stably maintained.

The invention discloses a heat treatment process of an alloy drill bit, which belongs to the field of alloy and comprises the following steps: S1, after the alloy drill bit is primarily machined and formed, carrying out vacuum pretreatment, heat preservation and heating; s2, the drill bit is rapidly transferred into a sectional temperature control carburizing furnace to be subjected to main carburizing treatment, the temperature is controlled between 930 DEG C and 960 DEG C, the carburizing time ranges from 3 hours to 4 hours, and the carburizing depth is controlled between 0.3 mm and 0.6 mm; s3, after carburizing is completed, subarea multi-speed cooling is carried out, quenching is carried out for 20 seconds at the temperature of 850 DEG C or above, controlled cooling is carried out for 60 seconds within the range of 550 DEG C to 650 DEG C, slow cooling is carried out for 80 seconds at the temperature of 200 DEG C or below, and a refined martensite complex phase structure is obtained; s4, after cooling is completed, double-section tempering treatment is carried out; and S5, performing ultrahigh-pressure static boriding diffusion treatment. The method has the beneficial effects that the processing uniformity, the structure stability, the wear resistance and the corrosion resistance of the alloy drill bit are effectively improved and the service life of the alloy drill bit is effectively prolonged by adopting staged temperature control, different cooling media and a directional quenching technology.

The invention discloses a coated titanium anode and an embedding preparation method thereof, and belongs to the technical field of coated titanium anodes, metal salt powder, an organic additive and inert filler are fully mixed to form embedding agent powder, the mass fraction of metal salt is 45-59%, the mass fraction of the organic additive is 1-5%, and the mass fraction of the inert filler is 40-50%; the sintering treatment is as follows: the pretreated titanium substrate is completely immersed in the embedding agent powder, the sintering temperature is 400-600 DEG C, the sintering time is 1-3 hours, and the heating rate is 5-10 DEG C / min. According to the method, low-temperature sintering is realized by precisely regulating and controlling the components and the proportion of the embedding medium and combining process parameters such as low-temperature sintering, and the damage to a titanium substrate is avoided; and meanwhile, the coating binding force of the titanium anode is improved, the service life of the titanium anode is prolonged, and technical innovation and industrial value are achieved.

The invention discloses a copper-molybdenum alloy component and a manufacturing method thereof, and belongs to the technical field of alloy manufacturing. Mo powder is sequentially subjected to vacuum drying treatment, oxidation-reduction treatment and coating treatment, so that the Mo powder has good flowability and powder laying uniformity; under the preset 3D printing condition, the porous Mo framework which is stably formed and complex in structure can be obtained, the problems that an existing rolling composite method is complex in technological process, strict in technological requirement and the like are solved, and the method is suitable for manufacturing parts with small sizes or complex shapes; the porous Mo framework is subjected to vacuum thermocuring and Cu infiltration treatment, and the obtained copper-molybdenum alloy component is excellent in compactness, high-temperature stability, interface bonding strength, heat conduction, electrical conductivity and the like. The problems that a copper-molybdenum alloy obtained in the prior art is poor in wettability and low in density and uniformity, and the mass content of copper is lower than 30%, so that the heat conductivity, the electric conductivity, the air tightness and other performance are low are solved.

The invention discloses a heat treatment process of a gear, which relates to the technical field of automobile gear heat treatment, and comprises the following steps: S1, blanking, S2, forging, S3, normalizing: preheating the gear in a preheating furnace by adopting a heating mode of combining infrared radiation and hot air circulation, S4, rough machining, S5, carburizing and quenching: carburizing and quenching, s6, induction heat quenching: performing induction heat quenching on an induction coil; S7, nitriding treatment; S8, low-temperature tempering; S9, finish machining; normalizing is combined with infrared radiation, hot air circulation preheating and induction heating, the effects of reducing energy consumption and machining cost and improving production efficiency are achieved, the forging force is reduced through isothermal forging, the energy consumption of equipment is greatly reduced, pulse type vacuum carburizing, high-pressure gas quenching and induction heat quenching are adopted to introduce a self-adaptive induction heating technology, and the energy consumption of equipment is greatly reduced. And a plasma nitriding technology and a composite nitriding technology are adopted, so that the surface hardness, wear resistance and fatigue strength are improved.

The invention relates to an MIM injection-molded samarium-iron-nitrogen magnet and a preparation process thereof.The preparation process comprises the steps that Nb is added into Sm2Fe17, a Nb nano-modified layer is formed through high-energy ball milling and heat treatment, then a degreased blank is obtained through a paraffin-polylactic acid-stearic acid ternary binder system with the mass ratio being 60: 30: 10 and gradient degreasing, and after the degreased blank is sintered, the MIM injection-molded samarium-iron-nitrogen magnet is obtained; nitriding treatment is carried out by adopting a three-stage process, and then the samarium-iron-nitrogen magnet with high magnetism is obtained after ultrasonic cleaning and other treatment.

The present application relates to a kind of Nb-Ti microalloying Cr-Mn gear steel and its preparation method, the chemical composition of the Nb-Ti microalloying Cr-Mn gear steel, by mass percentage, including: C:0.15~0.25%, Si≤0.20, Mn:0.8~1.60%, P:≤0.025%, S:0.010~0.035%, Cr:1.00%~1.80%, Ni:≤0.25%, Cu:≤0.20%, Ti:0.01~0.03%, Nb:0.02~0.07%, B≤0.0005%, Al:0.01~0.04%, [O]:≤12×10 ‑4 %, [N]:0.005~0.010%, [H]:≤1.5×10 ‑4 %, the rest is Fe and inevitable impurities.The Nb-Ti microalloying Cr-Mn gear steel prepared by the application has good hardenability, end hardenability J9=40~45HRc, J15=35~40HRc, which is greatly improved compared with 20CrMnTiH;The gear grain is refined, and the grain size reaches more than 7 levels after carburizing at 960~980 ℃ for 8~10 h, and the strength and toughness and fatigue performance of the gear are significantly improved.

To provide a steel component that exhibits excellent surface fatigue characteristic.SOLUTION: A steel component includes a nitride compound layer and a nitrogen diffusion layer from the surface to the inside thereof in this order. The nitrogen diffusion layer includes a carbonitride matching with a base phase ferrite, where, of the carbonitride, a carbonitride having a longitudinal length of 3 nm or more and 20 nm or less has the number densities of 1.0×1023 / m3 or more in a position of 50 μm inside from the surface, 0.3×1023 / m3 or more in a position of 200 μm inside from the surface, and 0.1×1023 / m3 or more in a position of 400 μm inside from the surface.SELECTED DRAWING: Figure 1

The embodiment of the invention discloses a gas phase infiltration device applied to a turbine blade. According to one specific implementation mode, the device comprises a lower base, a preheating chamber, a transition supporting seat, a multi-stage gas distribution chamber and an upper base which are coaxially arranged, the lower base is connected with a gas inlet pipeline, and mixed gas circulates in the gas inlet pipeline; the preheating chamber is arranged at the top end of the lower base, aluminum particles are contained in the preheating chamber, and the mixed gas enters the preheating chamber through the lower base and reacts with the aluminum particles to form process gas; the transition supporting seat is arranged at the top end of the preheating chamber; the multi-stage gas distribution chamber is arranged at the top end of the transition supporting seat and is connected with the preheating chamber; turbine blades are fixed in the multi-stage gas distribution chamber; the upper base is arranged at the top end of the multi-stage gas distribution chamber, the upper base is provided with a gas outlet hole, and process gas penetrates into the surface of the turbine blade through the multi-stage gas distribution chamber and is finally discharged through the gas outlet hole. According to the embodiment, the production efficiency can be improved.

The invention relates to the technical field of pipeline steel for oil and gas transmission, in particular to a novel low-C low-Cr corrosion-resistant pipeline steel plate, a preparation method and a pipeline steel pipe, and the novel low-C low-Cr corrosion-resistant pipeline steel plate comprises the following chemical elements: less than or equal to 0.03 wt% of C, less than or equal to 0.025 wt% of Sb, 0.50-1.20 wt% of Al, 0.0005-0.0012 wt% of Mg, 0.0012-0.0042 wt% of Ca, less than or equal to 0.50 wt% of Cr, 0.10-0.30 wt% of Ni, 0.10-0.30 wt% of Si, 1.20-1.80 wt% of Mn, 0.10-0.30 wt% of Mo, 0.02-0.06 wt% of Nb, 0.03-0.08 wt% of V, 0.01-0.03 wt% of Ti, less than or equal The manufactured steel plate is low in manufacturing cost, excellent in yield strength, tensile strength, ductility, impact toughness, corrosion resistance, hydrogen induced cracking resistance and other mechanical properties and suitable for seabed and land oil and gas conveying pipeline engineering in the high Cl <-> and CO2 / H2S corrosion environment.

The invention belongs to the field of hard alloy materials, and provides a modified high-performance non-magnetic hard alloy and a preparation process thereof. The surface of a WC particle is chemically plated with a Ni-P-B-Cr-Cu amorphous shell layer, and a binding phase is converted into Ni3P and Ni3B nanophase through two-stage sintering. The WC alloy comprises the following components in parts by weight: 85-95 parts of WC, 12-25 parts of a binding phase and 0.5-1.4 parts of a grain growth inhibitor, the nanophase accounts for 35-50% of the volume of the binding phase and 35-50% of the total volume of the binding phase, and the grain size is 80-125 nm; the average grain size of WC is 0.6-1.0 [mu] m; and the thickness of an interface P enrichment layer is 8-15 nm (the coverage rate is 85-95%). Through interface engineering and controlled crystallization from amorphous to nanocrystalline, the relative magnetic conductivity is 1.001-1.015, the hardness HRA is 90.5-93.0, the strength TRS is 2.2-3.0 GPa, the toughness KWP is 300-450 N / mm, and the magnetic saturation strength is 0.02-0.15 T. The problem of decoupling of the magnetic property and the mechanical property of a traditional non-magnetic hard alloy is solved, and the non-magnetic hard alloy is suitable for magnetic sensitive environments such as semiconductor equipment, precise measurement, MRI tools and oil service logging.

Methods of forming a fluoride or oxyfluoride layer for an optical element for use in the VUV wavelength range, which methods comprise: depositing an oxide layer; and converting the oxide layer into the fluoride or oxyfluoride layer by irradiating the oxide layer with UV / VUV radiation in the presence of an active fluorination agent. An optical arrangement has at least one such optical element. An associated device for forming a fluoride or oxyfluoride layer for an optical element is designed for use in the VUV wavelength range.

The invention discloses a wear-resistant alloy casting part for electric machinery and a production process thereof, and relates to the technical field of electric casting part optimizing.The production process comprises the steps that raw materials are smelted to 1550-1620 DEG C under the protection of argon, and heat preservation is conducted for 30-60 minutes; composite modification treatment; performing low-pressure sand mold casting or die-casting molding; after a casting is austenitized for 1.5-3 hours at the temperature of 980-1050 DEG C, two-stage isothermal quenching is conducted in a salt bath, specifically, in the first stage, heat preservation is conducted for 15-25 minutes at the temperature of 280-320 DEG C, and in the second stage, heat preservation is conducted for 45-60 minutes at the temperature of 180-220 DEG C; and surface laser cladding is conducted, specifically, homogeneous alloy powder is adopted for conducting laser cladding with the lap joint rate being 35-50% on the working face of the casting part. The method has the beneficial effects that through the design principle of multi-scale cooperative strengthening and the cross-dimension coupling effect of material components, the process path and the microstructure, breakthrough improvement of the performance of the wear-resistant alloy casting is achieved.

An austenitic Fe—Ni—Cr alloy has superior oxidation resistance even under extreme high temperatures and includes, in mass %: C: 0.004 to 0.13%, Si: 0.15 to 1.0%, Mn: 0.03 to 2.0%, P:≤0.040%, S:≤0.003%, Ni: 20.0 to 38.0%, Cr: 18.0 to 28.0%, Mo:≤1.0%, Cu:≤1.0%, N:≤0.03%, B:≤0.01%, Al: 0.10 to 1.0%, at least one of Ti: 0.10 to 1.0% and Zr: 0.01 to 0.6%, O: 0.0002 to 0.0030%, Ca:<0.002%, total weight of one or more from La, Ce, and Y: 0.001 to 0.010%, Fe as a remainder and inevitable impurities, and wherein the chemical composition satisfies formulae (1) and (2): 85≥0.3×Si+1.5×Ni+1.3×Cr+5.8×Al+7.7×Zr +2.7×Ti+2173×REM −3582×S ×32.9×Mo -2448×B≥47 . . . (1) 40≥0.6×Si+1.3×Cr +23.53×Al+5.88×Ti+3074×REM −5067×S −0.8×Mn −816×N≥. . . (2), and each element symbols indicates content of each element.

The invention discloses a high-strength stainless steel seamless steel pipe and a machining process thereof, and relates to the technical field of alloy treatment. The processing technology of the high-strength stainless steel seamless steel tube comprises the following steps: step 1, pretreating the stainless steel seamless steel tube to obtain a pretreated stainless steel seamless steel tube; 2, an ion nitriding process is adopted for conducting synchronous nitriding treatment on the inner pipe and the outer pipe of the pretreated stainless steel seamless steel pipe, and the nitrided stainless steel seamless steel pipe is obtained; and 3, the plasma spraying technology is adopted, the surfaces of the inner pipe and the outer pipe of the nitrided stainless steel seamless steel pipe are each coated with a compression-resistant protective layer, and the high-strength stainless steel seamless steel pipe is obtained through microwave treatment. Pretreatment, plasma nitriding treatment and plasma spraying treatment are sequentially conducted on the inner pipe and the outer pipe of the stainless steel seamless steel pipe with the specific component proportion, the compressive strength, the fatigue resistance and other performance of the inner pipe and the outer pipe of the stainless steel seamless steel pipe are synergistically enhanced, and the quality of the stainless steel seamless steel pipe is improved.

To provide a carburized component in which a stable carburized layer is obtained despite a high Cr material.SOLUTION: A carburized component is produced by carburizing a steel material in which a chemical composition is, by mass%, C: 0.10 to 0.35%, Si: 0.20 to 0.80%, Mn: 0.20 to 0.60%, P: ≤0.030%, S: ≤0.030%, Cr: 1.60 to 5.00%, Al: 0.003 to 0.050%, and N: 0.005 to 0.020%, and the remainder consists of Fe and inevitable impurities, and Cr+9.0Mn<8.6 is satisfied. In the carburized component, the hardness of a surface after carburization is 700Hv or more, and carbon content from the surface after carburization to the depth of 500 μm is 0.50 to 1.00%.SELECTED DRAWING: Figure 2

The invention discloses a water turbine nozzle sealing structure and a manufacturing method thereof, and relates to the field of water turbine nozzle sealing, the water turbine nozzle sealing structure comprises a spray needle and a wear ring, the spray needle and the wear ring are provided with flow passing surfaces, a sealing surface exists in the flow passing surfaces, and the sealing surface of the spray needle and the sealing surface of the wear ring are attached to form hard sealing; the spray needle and the wear ring are respectively provided with a base body, a nitriding layer and a coating are sequentially arranged from the base bodies to an overflowing face, and the surface of the coating is the overflowing face. According to the sealing structure, it can be guaranteed that the overflowing faces of the spray needle and the wear ring are high in hardness and good in wear-resisting effect, meanwhile, the problem that the silt impact resistance and the cavitation resistance are insufficient is effectively solved, and therefore the service life of the sealing structure is prolonged.

The invention provides a delayed cracking resistant 1800MPa level zinc-based coated steel plate, which comprises a substrate and a coating, the substrate comprises the following components in percentage by weight: 0.25%-0.35% of C, 0.15%-0.45% of Si, 1.50%-2.50% of Mn, less than or equal to 0.02% of P, less than or equal to 0.02% of S, 0.03%-1.50% of Al, 0.02%-0.10% of Nb, 0.02%-0.10% of Ti, less than or equal to 0.20% of V, less than or equal to 0.005% of B, 0.15%-0.60% of Cr, and Fe and other inevitable impurities; and the plating layer comprises the following components in percentage by mass: 0.15%-3.50% of Al and the balance of Zn. The invention further provides a manufacturing method of the delayed-cracking-resistant 1800MPa-grade zinc-based coated steel plate. The manufacturing method comprises the steps of smelting, casting, hot rolling and hot dipping. The invention further discloses a hot stamping method of the delayed-cracking-resistant 1800MPa-grade zinc-based coating steel plate. The hot stamping method comprises the steps of steel plate heating, steel plate cooling and hot stamping. According to the hot stamping forming part produced through the method, the strength of the steel plate is larger than 1800 MPa, the elongation is larger than 6%, and the steel plate subjected to hot stamping can meet the requirement that the steel plate does not crack after being bent for 120 hours at four points.