85results about How to "Avoid intergranular corrosion" patented technology

The invention discloses a welding method for low carbon steel-austenite stainless steel compound pipe of ultra-thin stainless composite bed. The character is: the welding is completed with transition layer welding seam and base layer welding, it hasn't single stainless steel composite bed seam; the welding rod for low carbon steel base layer seam is the same to the one for mother metal; the first welding for stainless steel composite layer and the transition layer between the stainless composite layer and the low carbon steel base layer use argon tungsten-arc welding with back argon filling protection, or uses manual arc welding; the welding wire or welding rod use stainless steel in order to form the transition welding seam; after the transition welding seam is completed, the second time uses manual arc welding to weld the low carbon steel base layer, the welding rod uses low carbon steel in order to form base layer welding seam.

The invention discloses a high-strength corrosion-resistant aluminum alloy profile and a preparation method thereof. The aluminum alloy profile comprises an aluminum alloy base body and a ceramic coating. The aluminum alloy base body is prepared from Cu, Si, Fe, Cr, Mg, Mn, Zn, Ti, Li, Ni, Zr, Y, W, V and the balance Al. The ceramic coating is prepared from SiC, Cr2O3, NiO, Cr3C2, Al2O3 and Si3N4. According to the high-strength corrosion-resistant aluminum alloy profile, ceramic powder is arranged on the surface of the aluminum alloy base body through plasma cladding, and then laser remelting is conducted, so that the obtained aluminum alloy profile has good mechanical performance such as strength, hardness and impact toughness; and meanwhile, the high-strength corrosion-resistant aluminum alloy profile has the beneficial effects of being resistant to corrosion, good in abrasion resistance, long in service life and the like.

The invention relates to an SUS304 stainless steel cold-rolled plate producing method which omits annealing before cold rolling. The method comprises the steps of smelting, casting, hot rolling, cooling, pickling, cold rolling, solution treatment and pickling, wherein a plate blank is heated to a temperature higher than 1270 DEG C, a hot coil-box is used for temperature preservation before the hot rolling, and the finishing temperature is over 1000 DEG C; cooling is carried out after the rolling, the cooling speed is 25-40 DEG C/s, and coiling is carried out until the coiling temperature reaches 601-650 DEG C; and within 60 minutes after the coiling, a hot rolled coil is positioned in a water tank for cooling, and the hot rolled coil is taken out after the cooling is carried out for 5 or more hours. The method ensures that the SUS304 uniforms crystal grains as much as possible in the process of hot working, avoids corrosion caused by carbide precipitation, realizes the same effect as the adoption of off-line solution treatment, leads to the omission of the off-line solution treatment before the process of cold working and solves the problem that the omission of the off-line solution treatment brings changes to the roll scale structure of the SUS304 hot rolled coil.

The invention discloses a multi-curvature forming method for a stainless steel cylinder. The method is characterized by comprising the following steps: performing scribing and blanking according to the developed length of the medium diameter of a cylinder to be wound; machining peripheral welding grooves of a plate; rolling-forming a first-curvature circular arc, namely reserving a straight section, not to be wound for the formation of a circular arc, with a width B of 200 to 600 mm at each of the two ends of the cylindrical plate, and bending and winding the middle part of the cylindrical plate into a large circular arc with a curvature radius R of more than or equal to 0.5 Phi to form the first-curvature circular arc of the cylinder; rolling-forming second-curvature circular arcs, namely rolling the parts between the roots of the straight sections with the widths B of 200 to 600 mm and the large circular arc into circular arcs with curvature radiuses r of 0.2 to 0.5 Phi to form second-curvature circular arcs; rolling transition parts between the second-curvature circular arcs and the first-curvature circular arc into smooth transition; performing rolling until the grooves 2 in the two ends of the straight sections get close to each other; performing longitudinal seam assembly and welding on the cylinder, placing the cylindrical body at a horizontal position, and welding longitudinal seams; performing roundness correction on the cylinder after welding.

A continuous annealing and acid washing method for medium-chromium ultrapure ferrite stainless steel comprises the process flow of cold rolling, annealing heat treatment, acid washing, final water washing, drying, flattening and packaging, and is characterized in that in the acid washing process flow, the acid washing solution is prepared from 120-150g/L of 65% nitric acid, 2-4g/L of 40% hydrofluoric acid and water. According to the invention, in the chemical acid washing stage, reasonable concentration ratio of nitric acid to hydrofluoric acid is adopted and proper acid washing speed is controlled to carry out acid washing on medium-chromium ferrite stainless steel. As a result, on one hand, the performance of a medium-chromium ferrite stainless steel passivation film is obviously improved, and the corrosion resistance of the surface of a medium-chromium ferrite stainless steel 2B board is significantly improved, and on the other hand, the process flow of the existing production factory is not needed to be changed, a special passivation treatment procedure is not needed, and the production cost is significantly lowered.

The invention provides a production method of a composite material stirring wing. The method comprises the following steps of: (1) wax pressing process; (2) shell making process; (3) dewaxing process; (4) roasting process; (5) composite material smelting process; (6) clean sand pouring process; (7) sprue removing and cleaning process; and (8) heat treatment process. The production method can be used for producing the stirring wing with high safety and reliability, and the high-quality composite material stirring wing can be produced by the method.

The invention relates to a deformation zinc alloy, as well as a preparation method and a use thereof. The deformation zinc alloy comprises 2.0-9.5% of Cu, 0.01-0.5% of Mn, 0-0.1% of Co and the balance of zinc and inevitable impurity elements, wherein the total amount of the inevitable impurity elements is less than 0.01. The microstructure of the zinc alloy mainly comprises a zinc matrix primary phase and intermetallic compounds dispersed in the primary phase, wherein the primary phase is of an HCP (hexagonal close-packed) structure, and the intermetallic compounds are of small Zn4Cu and Zn9Mn; the volume content of the Zn4Cu phase is 5%-55%, the volume content of the Zn9Mn phase is 0.1%-5%, and the balance is of the primary phase; and the average grain size of the primary phase is 15-35 mu m, and the average grain size of the intermetallic compounds is 5-15 mu m. The alloy can be produced into screw nuts and screw caps for air conditioners for replacing traditional brass and further solving the problem of being short of brass resources through post-processing technologies, such as melting-casting, extrusion, drawing and the like under certain process conditions.

The invention discloses a medium chromium base ferrite stainless steel erosion agent and preparing and erosion methods thereof, and belongs to the technical field of medium chromium base ferrite stainless steel tissue erosion observation. The erosion agent comprises, by volume, 10-80 parts of ethyl alcohol, 20-90 parts of nitric acid, 50-100 parts of hydrochloric acid and 50-200 parts of distilled water. The preparing method of the erosion agent includes the steps that the ethyl alcohol and diluent nitric acid are evenly mixed to prepare a nitric acid and ethyl alcohol mixing solution; then the distilled water and the hydrochloric acid are evenly mixed to prepare a hydrochloric acid and distilled water mixing solution; and finally, the nitric acid and ethyl alcohol mixing solution and the hydrochloric acid and distilled water mixing solution are evenly mixed to prepare the erosion agent. According to the creative technical scheme, the effective erosion agent and erosion method are provided for medium chromium base ferrite stainless steel, and therefore technical supports are provided for observation of macrostructures in the medium chromium base ferrite stainless steel.

The invention relates to a Zn-Al-Mg alloy layer used for being hot-dipped to a bridge steel wire surface and a manufacturing method for the Zn-Al-Mg alloy layer. The alloy layer comprises, by mass, 30%-97% of Zn, 5%-60% of Al and 0.02%-11% of Mg, wherein the sum of the percentages of all the components is 100%. The manufacturing method includes the steps that a bridge steel wire is unoiled and derusted; the alloy layer is hot-dipped; and stabilizing treatment is conducted. According to the alloy plating layer, the corrosion resistance is superior to that of an existing zinc plating layer and that of an existing zinc aluminum alloy plating layer, the alloy plating layer is easy to use, meets the requirements of the special environments, such as the requirement for bridge steel wires in the marine corrosion atmosphere environment and has wide market prospects.

The invention relates to the field of ocean engineering, and particularly discloses an erosion-resistant copper alloy utilized in an ocean working condition and a preparation method thereof. The copper alloy comprises the following elements by mass percent: 7% to 10% of Ni, 5% to 10.5% of Al, 0.15% to 1% of Fe, 0.5% to 1.5% of Mn, 0.15% to 1% of Ti, 0.05% to 0.15% of P, 0.2% to 0.6% of Mg and 0.005% to 0.01% of B, and the balance being copper. The preparation method comprises the steps of sequentially adding electrolytic copper, a covering agent, a CnMn intermediate alloy, a CuCo intermediate alloy, CuFe intermediate alloy, electrolytic nickel, pure chromium, electrolytic aluminium, pure silicon and the covering agent; and then, carrying out phosphor copper deoxidation, stirring slag salvaging, temperature increasing and discharging. The preparation method has the advantages that cost is low and efficiency is high, the copper alloy material has performance like sandy seawater erosion corrosion resistance, ocean organism corrosion resistance and seawater high-speed flow corrosion resistance, and the requirement of ocean engineering on corrosion-resistant and abrasion-resistant materials can be met.

The invention relates to a corrosion resistance and high temperature resistance magnesium alloy wheel hub and a preparation method thereof. A magnesium alloy comprises, by mass, 4.0-6.5% of Al, 1.2-3.0% of Zn, 0.8-1.5% of Mn, 0.1-3.3% of Yb, 0.3-0.8% of N, 0.8-2.3% of Si, 18-25% of Cr, less than or equal to 2.5% of W, 0.2-0.6% of Zr, and the balance Mg and inevitable impurity elements. The outer surface of the wheel hub is treated by micro arc oxidation to form a ceramic film on the product surface and then baked and coated with paints. According to the corrosion resistance and high temperature resistance magnesium alloy wheel hub and the preparation method thereof, the ceramic film is formed on the product surface through the micro arc oxidation treatment, so that the surface strength isstrengthened, the damage of a protective layer caused by the wear, bump and scratch of a wheel is avoided, and the corrosion resistance, high temperature resistance and aesthetics of the wheel hub aregreatly improved.

The invention discloses a 110ksi-grade stainless steel oil pipe and a manufacture method thereof. The 110ksi-grade stainless steel oil pipe consists of the following chemical components in a percent by mass: smaller than or equal to 0.02 of C, smaller than or equal to 0.20 of Si, 1.00-1.50 of Mn, 18-20 of Cr, 9-12 of Ni, 0.1-0.3 of N and the balance of Fe and trace impurity elements, and the 110ksi-grade stainless steel oil pipe is finally obtained after the chemical components are treated by the procedures of smelting, forging, pipe blank making, extrusion and rolling, solid solution treatment, cold deformation, heat treatment, non-destructive detection and pipe end machining. The yield strength Rp0.2 of the 110ksi-grade stainless steel oil pipe is 758-828MPa, the tensile strength Rm is larger than 862MPa, and the elongation A50 is larger than 12%. The 110ksi-grade stainless steel oil pipe meets the requirements of API Spec 5CT standards on 110ksi strength grade and is suitable for meeting the requirements of deep and superdeep wells and oil wells in severe corrosive environments.

The invention discloses a combined solar photovoltaic module frame. The combined solar photovoltaic module frame comprises a main body frame; the main body frame is composed of a long frame, a short frame and a U-shaped fixing block; the long frame and the short frame are matched; the short frame is composed of a first concave profile, fixing edges and a first connection block; the fixing edges are arranged at two ends of the first concave profile; the first connection block is formed by extension from one side of the first concave profile; a first groove and a glue injecting groove are also arranged at the notch of the first concave profile; locating holes are also arranged at two ends of the first concave profile; a fixing block is also arranged on the fixing edge; the long frame mainly comprises a second concave profile; a second groove is arranged at the notch of the second concave profile; extension plates extend from two ends of the second concave profile; a locating column is arranged on the extension plate; and a fixing hole is also formed on the side surface of the extension plate. The invention further designs a production process of the combined solar photovoltaic module frame. The aluminium frame is simple in structure, good in protection performance, low in cost and convenient to disassemble and install; furthermore, the aluminium frame can be individually used; and furthermore, multiple aluminium frames can be used in a combined manner.

The invention relates to a corrosion-resisting austenitic stainless steel submerged-arc welding wire and a production method thereof. The corrosion-resisting austenitic stainless steel submerged-arc welding wire is composed of, by mass, 0.015%-0.025% of C, 1.00% of Si or the less, 2.50% of Mn or the less, 0.020% of P or the less, 0.010% of S or the less, 12.00%-14.00% of Ni, 18.00%-20.00% of Cr, 2.00%-3.00% of Mo, 0.05%-0.10% of N and 0.05%-0.10% of Ti. The production method comprises the following steps that dosing, vacuumizing, argon gas filling, energizing, fine melting, cooling, ferrosilicon adding, carbon adding, titanium adding, power cutting and pouring are conducted, and a steel ingot is obtained after cooling; and then steel forging, steel rolling, welding wire finishing drawing and finished product heat treatment are carried out. According to the corrosion-resisting austenitic stainless steel submerged-arc welding wire, an element Nb is replaced with an element Ti, coarsening of austenite crystal grains can be effectively prevented, refining of ferrite crystal grains is achieved, intercrystalline corrosion is avoided, and the corrosion resistance of a welding wire deposited metal is improved. Meanwhile, due to the effect of nickel equivalent elements such as Ni, Mn, C and N which are favorable for formation of austenitic stainless steel, strength of the welding wire deposited metal can be effectively improved, and additionally, the price of titanium is low, so that the production cost can be reduced.

The invention discloses a high-pressure silencer suitable for performing noise elimination and noise lowering on discharged high-pressure gas. The high-pressure silencer comprises a shell, noise eliminating bodies and a silencing material; one end of the shell is a cylinder of a spherical end socket which is provided with a gas inlet connection nozzle; the other end of the shell is closed through a hole plate with exhausting holes; the portion, close to one end of the spherical end socket, in the shell is provided with the noise eliminating bodies with the noise eliminating level number being N; one end of the first level of noise eliminating body is connected with the gas inlet connection nozzle; the noise eliminating bodies of all the levels are each provided with a vent hole, are each in a round pipe shape and are arranged in a concentric sleeved manner; and the portions between the inner wall of the shell and the outer sides of the noise eliminating bodies are filled with the silencing material, wherein N is larger than or equal to 4 and is a natural number. High-pressure gas flow enters the noise eliminating bodies from the gas inlet connection nozzle, the volume is gradually increased, the density is continuously decreased, noise is gradually weakened, the weakened gas flow enters the silencing material and is further weakened, and when the gas flow reaches the hole plate, the noise is finally weakened substantially. The high-pressure silencer is good in silencing effect, simple in structure, high in strength, convenient to install and easy to maintain.

The invention discloses a corrosion-resistant and wear-resistant high strength electrophoretic aluminum profile and a preparation process thereof and belongs to the field of aluminum profile preparation. The corrosion-resistant and wear-resistant high strength electrophoretic aluminum profile is prepared from the following raw materials in percent by weight: 0.8-1.2% of Mg, 0.4-0.6% of Si, 0.2-0.4% of Ti, 0.22-0.3% of Fe, 0.06-0.1% of Cu, 0.08-0.12% of Zn, 0.06-0.08% of Cr, 0.12-0.18% of Mo and the balance of Al and inevitable impurities. The preparation process is simple and effective and convenient and rapid in process operation. By controlling the contents of Mg, Si, Fe, Cu and Zn reasonably, strengthening phases such as Al2Cu, Al2CuMg, Mg2Si, MgZn2 and the like are formed in the electrophoretic aluminum profile to strengthen the synergistic effect, refine crystals and improve grain distribution, so that performance, such as wear resistance and corrosion resistance, of the electrophoretic aluminum profile is improved. By matching Si, Ti, Fe, Cr and Mo, the grains are refined, the cast structure and the weld joint structure are refined, the recrystallization temperature is increased, the thermal stability of a material is improved, the intergranular corrosion is avoided, and the corrosion performance of the electrophoretic aluminum profile is improved.