66results about How to "Uniform surface hardness" patented technology

The invention provides an electric pressure cooker control method which comprises the following steps that an electric pressure cooker is controlled to heat with first power; when a first preset condition is met, a pressure valve is opened, so that air is discharged; the electric pressure cooker is controlled to heat with second power until the temperature in the electric pressure cooker is stable and food in the electric pressure cooker is made to be turned over completely; the pressure valve is closed and the electric pressure cooker is controlled to heat with third power, so that the electric pressure cooker enters a boosting stage, and the third power is smaller than the first power and the second power; when a second preset condition is met, the electric pressure cooker is controlled to heat with fourth power, so that the electric pressure cooker enters a pressure maintaining stage. According to the electric pressure cooker control method, the cooked food is complete, moisture is sufficient, the hardness is even, the taste is good, and the cooked food is prevented from pasting the bottom of the cooker and overflowing out of the cooker. The invention further provides the electric pressure cooker.

This invention involves a kind of step quenching process which is suitable for Bainitic and Martensite quenching and the equipment utilizing this step quenching process. The workflow includes: heating, quenching in low-temperature nitrate groove and isothermal; turn to oil grooves to cool down, wash and dry; turn to air furnace for isothermal temper. The above step quenching is performed in roller hearth furnace production line. After adjusting the technology parameter, this production line can undergo Bainitic step quenching and Martensite step quenching. This production line is composed mainly by roller hearth heating furnace, nitrate groove, oil groove, cleaner, dryer and temper furnace. This invention can improve the heat treatment quality; reduce the amount of nitrate and pollution. This production line can undergo normal Martensite quenching, Martensite step quenching and Bainitic step quenching, so to reduce investiment and increase the effeiciency.

The invention discloses a high-efficient energy-saving and surfacing layer well-forming self-shielded flux-cored welding wire. A low-carbon steel belt is an outer skin; and a flux core comprises the following components in percentage by mass: 42-60% of high carbon ferro-chrome with the particle size of 80 meshes, 10-18% of ferrosilicon, 16-25% of ferroboron, 2-8% of rare earth silicon, 2-8% of graphene, 1-4% of aluminum magnesium alloy, 2-5% of manganese powder and the balance of iron powder, wherein the graphene, the aluminum magnesium alloy and the manganese powder are added with two kinds of particle sizes of 60 meshes and 200 meshes, and the weight of the flux core powder accounts for 49-53% of the total weight of the welding wire. According to the welding wire provided by the invention, by adding the flux core components with different particle sizes, good welding technological performance is ensured; and by adding B, Si and other self-fluxing alloy elements simultaneously in the flux core, the fusing point of the welding wire is effectively lowered; a welding process window is expanded; the surfacing efficiency is improved; a high-efficient and energy-saving effect is realized; and the surface tension of a surfacing welding bead is effectively lowered, and the forming of the surfacing welding bead is effectively improved.

The invention discloses a quenching tank for the large and medium size forging, comprising a body and submersible mixers which are mounted at the periphery and bottom of the inner wall of body. The submersible mixers are positioned at the middle in the height direction of each side of inner wall, at the two middle points of the trisected distribution of the inner wall in the length direction of each side inner wall. Thirteen submersible mixers are mounted at the bottom of the body and in the regular five-row and five-line lineup distribution. Each submersible mixer in the bottom of the body is connected with a frequency conversion controller by a line, the rotating speed of each submersible mixer can be controlled by the frequency conversion controller, thus a uniform temperature area is formed in the quenching solution in the body. The invention has simple structure, easy production, maintenance and use, and is mainly used for the quenching of large and medium size forging.

The invention provides a method for increasing the surface hardness of 18Ni300 die steel for metal 3D printing. The method comprises the following steps that S1, a die is printed; S2, solid-soluble heat treatment of a part is conducted; S3, wire cutting and powder clearing of the part are conducted; S4, parts surface treatment is conducted; S5, part surface coating preparation and coating are conducted; S6, heat treatment is conducted; and S7, machining is conducted, specifically, 0.3-0.5 mm of a part surface coating is removed as machining allowance. According to the method for increasing thesurface hardness of the 18Ni300 die steel for metal 3D printing, an NiCrBSi coating can be evenly applied to the surface of the die part through a plasma spraying process, the surface hardness is uniform, and the surface hardness of the die can reach 56-65 HRC.

The invention provides a laser shot blast-rolling reinforcement compound device of a rotary body and a method thereof. The laser shot blast-rolling reinforcement compound device comprises a laser emitting device, a light path conveying device, a numerical control platform and a rolling head; the laser emitting device is used for generating laser beams; one end of the light path conveying device isused for inputting the laser beams, the other end of the light path conveying device is provided with the rolling head, and the rolling head is in contact with the rotary body and used for carrying out rolling reinforcement on the surface of the rotary body while the laser beams are enabled to penetrate through the rolling head so as to perform laser shot blast on the surface of the rotary body;the rotary body is fixed by the numerical control platform through a first rotating device; and the numerical control platform is used for fixing the light path conveying device through a second rotating device, which is used for enabling the rolling head to rotate around the rotary body. According to the laser shot blast-rolling reinforcement compound device of the rotary body and the method thereof, a pressure spring in the rolling head is adjusted to obtain the required rolling load, a laser is guided through the light path system, automatic focusing of the laser shot blast process is realized, and compound surface reinforcement of a complex curved surface can be accurately realized.

The invention discloses a modified hardfacing self-shielded flux-cored wire doped with multi-boride and a preparation method of the modified hardfacing self-shielded flex-cored wire doped with the multi-boride. The modified hardfacing self-shielded flux-cored wire doped with the multi-boride comprises a low-carbon steel strip and a flux core, wherein the flux core comprises, by mass percentage, 45-55 wt% of high carbon ferro-chrome, 6-16 wt% of B4C, 3-9 wt% of TiB2, 3-9 wt% of ZrB2, 1-3 wt% of graphite, 0.5-1 wt% of cellulose powder with the mesh being 60, 0.5-1 wt% of cellulose powder with the mesh being 200, 1-3 wt% of an aluminum-magnesium alloy with the mesh being 60, 0.5-2 wt% of an aluminum-magnesium alloy with the mesh being 200, 2-7 wt% of an silicon-manganese alloy with the mesh being 60, 1-4 wt% of an silicon-manganese alloy with the mesh being 200 and the balance iron powder, and the flux core accounts for 50-54 wt% of the total mass of the flux-cored wire. According to the flux-cored wire, through addition of the flux core components of different grain sizes, the good welding process performance is guaranteed; through the addition of the multi-boride component, the multi-boride is dispersed and extracted in the welding process; and the flux-cored wire has the beneficial effects of being high and uniform in hardness, good in wear resistance and the like, and few residues are left on the surface of a weld bead, and slag removal is not needed in multi-layer welding.

The invention discloses a manufacturing method for an airplane part stretch-forming mold made of a resin matrix composite and mainly aims to solve the problems that existing molds are large in manufacturing difficulty, hard to store and large in weight and cannot be repaired. The provided manufacturing method for the airplane part stretch-forming mold made of the resin matrix composite comprises the steps that a matrix and a surface are manufactured with the resin matrix composite; and then the airplane part stretch-forming mold is machined and manufactured through a numerical control machine tool. By means of the manufacturing method, the mold using rate is increased, especially, the part productivity is improved, the mold manufacturing cost is reduced, and the mold manufacturing period is shortened.

The invention discloses an in-situ synthesis WC and W6C type carbide self-protection strengthening build-up welding flux-cored wire. A low carbon steel strip is used as an outer cover; a flux core comprises the following components in percentage by weight: 6-12% of high-carbon ferromanganese, 50-60% of tungsten powder, 6-12% of electrolytic manganese powder, 8-12% of graphite, 1-3% of ferroboron, 1-3% of an aluminum magnesium alloy, 1-3% of silicomangan and the balance iron powder, wherein the ferroboron, the aluminum magnesium alloy and the silicomangan are added in two particle sizes including 60 meshes and 200 meshes; and the weight of the flux core accounts for 50-55% of the total weight of the flux-core wire. According to the welding flux-cored wire provided by the invention, components of the flux core in different particle sizes are added, so that favorable welding process performance is guaranteed; through an appropriate compounding ratio with other alloy powder, an eutectic crystal consisting of first-separated WC carbide, W6C and part of martensite is formed in the build-up welding alloy structure; the hardness of a build-up welding layer is as high as 62-66HRC, so that the in-situ synthesis WC and W6C type carbide self-protection strengthening build-up welding flux-cored wire disclosed by the invention is good in abrasion resistance, favorable in welding process performance, and high in depositing efficiency, and multilayer welding is free from removing slags.

The invention relates to a roller production method. The roller production method comprises the following steps: (S1) a cover having an air port is arranged outside a mandrel; and alloy powder is filled in the cover while setting; (S2) air is extracted from the air port of the cover to degas the alloy powder in the cover; (S3) the air port is sealed to form a transition part; (S4) the hot isostatic pressing treatment is performed for the whole cover containing the mandrel inside, so that the alloy powder is sintered to form a roller sleeve; and (S5) the cover is disassembled and machined to form a roller with size and surface quality accordant with requirements. In the roller obtained by the roller production method, the bonding place between the mandrel and the roller sleeve is a metallurgical bonding interface; the bonding is tight; no carbide is separated out from the bonding place; and the content of nonmetal inclusions in the roller sleeve is low. The tissue in the bonding place is free of segregation; the component distribution is more uniform; the surface hardness of the roller sleeve is uniform; the product surface quality is greatly improved; and finally, the service life of the roller is largely prolonged.

The invention relates to a medium manganese steel lining material for a ball mill and a preparing method of the material, and belongs to the technical field of wear-resisting materials. The medium manganese steel lining material for the ball mill is composed of components including, by mass percent, 0.2 to 0.6% of carbon, 5.0 to 8.0% of manganese, 0.1 to 0.3% of silicon, not larger than 0.015% ofphosphorus, not larger than 0.015% of sulphur, 0.01 to 0.05% of niobium, 0.3 to 0.8% of chromium and the balance iron. According to the medium manganese steel lining material for the ball mill, methodof vacuum smelting and pressure casting is adopted for preparing. The mechanical property and the wear-resisting performance of the medium manganese steel lining material for the ball mill are excellent, the anti-bending strength reaches 821 MPa, the hardness reaches 55HRC, the impact power of a V-shaped sample reaches 30J, and the service life is prolonged by more than 25% compared with a traditional high manganese steel lining plate.

The invention discloses a hot roller supersonic spraying surface repair pretreatment method. The hot roller supersonic spraying surface repair pretreatment method comprises specific procedures of 1) concave cutting treatment, 2) surface cleaning, 3) surface plate shape formation and 4) surface roughening, wherein the surface roughening specifically comprises the following steps: (1) similar vertical strip patterns are formed through primary sand blasting; and the roughness is controlled within Ra 2.5-3.2; (2) a roller is stopped rotating; two sample plates are fixed on the surface of the roller after primary sand blasting; a sand blasting gun blasts sand in a spiral gap between the two sample plates; and the roughness is controlled within Ra 5.5-6.5; (3) the two sample plates are overturned and fix on the surface of the roller after secondary sand blasting; the sand blasting gun blasts sand in the spiral gap between the two sample plates; and the roughness is controlled within Ra 5.5-6.5; and (4) the hot roller is preheated. The method can obtain a supersonic spraying layer with high bonding strength and higher wear resistance, prolongs the service life of the roller, and reduces the production cost.

The invention discloses hot rolling alloy steel for a train brake disc. The hot rolling alloy steel comprises C, Si, Mn, Cr, N, Mo, V and Fe. C, Si, Mn, Cr, Ni, Mo and V are evenly doped and distributed in a steel base body according to the specific proportion, and the abrasion resistance of a material is greatly improved while the mechanical performance of the material is guaranteed. The material has good forming performance, the braking disc close to the final shape can be prepared, and later machining of a traditional preparing method is reduced. By means of control over the content range of C and Mn, the material cooling speed is increased, and the material strength and surface hardness are improved.

The invention discloses a forged steel cold rolling roller cryogenic treatment method and a novel nozzle adopted by the same. The nozzle is provided with a mounting part and a nozzle head, wherein thenozzle head is provided with a large nozzle port with the diameter of 0.8 mm to 1.2 mm and a plurality of small nozzle ports provided with the diameters of 0.4 mm to 0.6 mm and arranged on the periphery of the large nozzle port. The cryogenic treatment method comprises the following steps that (1) a forged steel cold rolling roller is placed in a cryogenic box, and the cryogenic box is closed; (2) liquid nitrogen is sprayed into the cryogenic box from the nozzle, and the temperature in the cryogenic box is lowered to -160 DEG C to -120 DEG C through 1 h to 2 h; (3) the temperature is kept for 2 h to 5 h at the temperature; and (4) after keeping of the temperature is finished, the cryogenic box is opened, and the forged steel cold rolling roller is placed under a room temperature environment to be naturally restored to the room temperature. According to the forged steel cold rolling roller cryogenic treatment method and the novel nozzle adopted by the same, the novel nozzle is designed, and the corresponding cryogenic treatment method is adopted for matching so that the sprayed liquid nitrogen can be more dispersed and more uniform, so that the surface hardness of the forged steelcold rolling roller is more uniform, the hardness uniformity of the finished product is improved, and the blockage phenomenon of the nozzle is also greatly reduced.

The invention discloses a machining method of air suction grooves of a corrugated roller. The machining method includes the first step of earlier-stage processing specifically involving the processes of a matrix modulation, b primary machining, c tooth punching and d multiplex heat treatment which are conducted on the corrugated roller in sequence, the second step of grinding of the air suction grooves, and the third step of turning of the air suction grooves. The machining method has the beneficial effects that the surface hardness of the roller reaches above HRC62, and the wear life of the roller is prolonged by 30%; the corrugated roller is uniform in surface hardness and free of soft zones; in the using process, neither pocking marks nor concave pits occur; due to the fact that hardening treatment is conducted at first and then the grooves are cut, the hardness of groove openings is consistent with the hardness of other positions, and the defect that poor gluing of paper boards is caused by quick abrasion to the groove openings, tooth breakage and other reasons is avoided in the using process.

The invention discloses a self-generated wear-resistant surfacing self-protected flux-cored wire reinforced by boron carbide with great volume fraction and a preparation method for the self-generated wear-resistant surfacing self-protected flux-cored wire. By taking a low-carbon steel belt as skin, the flux-cored wire consists of the following components in percentage by mass: 52-62% of high carbon ferro-chrome, 2-6% of chromium powder, 22-30% of ferroboron, 2-4% of graphite, 1-3% of an aluminum-magnesium alloy, 4-8% of a silicon-manganese alloy, and the balance iron powder; the graphite, the aluminum-magnesium alloy and the silicon-manganese alloy are added with grain sizes being 60 meshes and 200 meshes; and the flux core powder accounts for 55-60% of the total weight of the flux-cored wire. According to the flux-cored wire provided by the invention, flux core components with different grain sizes are added, so that good welding process performances are guaranteed; the flux core components are reasonably proportioned with other flux core components, so that boron carbide with mass fraction being 90% or more, namely (Cr, Fe)7(C, B) 3 and (Cf, Fe)3(C, B), is obtained in a surfacing alloy structure, hardness of a surfacing layer is as high as 65-68 HRC, and wear resistance of abrasives resistant to low stress is extremely good; and the welding process performances are good, deposition efficiency is high, and multi-layer welding is carried out while slag does not need to clear.

The invention belongs to the technical field of heat treatment of high-temperature alloy forgings, and discloses a heat treatment method for GH99 alloy annular forgings, which comprises the following steps: heating the forged GH99 alloy forgings to 1100 DEG C, preserving heat for 1-3 hours, carrying out air cooling and precooling on the forgings for 1-5 minutes after discharging, and then carrying out water cooling. Compared with a conventional GH99 alloy heat treatment method, layered staggered placement is adopted for heat treatment charging of the annular forge piece, it is guaranteed that each face of the forge piece is cooled uniformly, the treated forge piece is uniform in structure, and the hardness of the surface and the core of the forge piece is uniform; according to the method, after solid solution heat preservation is finished, the cooling mode that air cooling and pre-cooling are conducted firstly, and then water cooling is conducted is adopted for cooling, so that the difference between the surface cooling rate and the core cooling rate of the forge piece is reduced, the hardness HB (d) of the treated forge piece is within the range of 3.6-3.9 mm, the strength surplus amount is large, and the delivery and use requirements are met.

The invention discloses a method for eliminating color differences of a machined surface of an electroslag martensite circle forging machine. According to the method, the mechanism of electroslag steel forging circle color difference generation is researched according to the personalized requirements of a user for surface color differences, besides normal electroslag process control, the forging circle heat treatment process is optimized and improved with post-forging heat treatment process optimization as a thinking starting point, and two annealing processes are formulated. The problem of the color differences after machining of the electroslag martensite round forging surface is solved, and user requirements are met.