40results about How to "Increase the solidification rate" patented technology

The invention discloses sulphuric acid dew point corrosion resisting steel and a method for producing the same by continuously casting and rolling a thin steel billet with an electric furnace. The molten steel comprises the following chemical components by weight percent: 0.03-0.08 percent of C, 0.10-0.45 percent of Si, 0.40-1.0 percent of Mn, 0.025 percent of P or less, 0.035 percent of S or less, 0.15-0.50 percent of Cu, 0.40-1.0 percent of Cr, 0.02-0.15 percent of Sb, 0.04-0.30 percent of Ni and 0.01-0.05 percent of Ti and also comprises 100ppm of N or less. The thin steel billet is continuously cast at the speed of 3.5-5.5m/min, and the cast thin steel billet is placed in the electric furnace of 900-1050 DEG C, soaked at 1100-1200 DEG C, rolled at 1040-1120 DEG C, finally rolled at 850-920 DEG C and winded at 550-650 DEG C. The Cu-Cr-Sb composite micro-alloyed sulphuric acid dew point corrosion resisting steel having good mechanical performance, welding performance and corrosion resisting performance can be produced by continuously casting and rolling the thin steel billet with the electric furnace.

A preparation method of Waspalloy spherical powder for additive manufacturing includes the steps of conducting alloy component compounding according to AMS 5706 standards and subjecting master ingots to vacuum melting twice; producing the master ingots into alloy electrode bars by means of forging and machining; subjecting an atomizing unit to pre-vacuum-pumping treatment, and feeding the atomizing unit with mixed inert protective gas; feeding the electrode bars into an atomizing chamber by a feeding system, heating electrode bar end faces by a plasma torch, preparing metal liquid droplets under the centrifugal action of a rotating electrode, and making the metal liquid droplets form spherical metal powder by flash setting; using a powder collecting device comprising an electrostatic separation component for removing inclusions of the spherical metal powder and collecting purified powder. The preparation method has the advantages of high production efficiency, high batch stability and high -270-mesh powder yield and can be used for easily preparing the Waspalloy spherical powder high in purity, sphericity and fluidity.

The invention provides a preparation method of high-nitrogen stainless steel spherical powder. The preparation method comprises the following steps: preparing materials according to stainless steel components and carrying out a melting process of a mother alloy ingot; preparing the mother alloy ingot into a common stainless steel electrode bar through forging and machining; carrying out pre-vacuumizing treatment on atomization equipment and introducing high-purity nitrogen gas; conveying the electrode bar into an atomization chamber through a feeding system and heating the end face of the electrode bar by using a plasma torch; ionizing the nitrogen gas in an electric arc region into nitrogen ions, high-energy nitrogen molecules and un-ionized nitrogen neutral atoms so as to improve the nitrogen content of stainless steel; preparing metal liquid drops by using a centrifugal effect of a rotary electrode and instantly condensing the metal liquid drops into spherical metal powder; after cooling the high-nitrogen stainless steel spherical powder, removing non-metal impurities through an electrostatic impurity removing device; and finally, carrying out powder package by adopting multilayered vacuum heat sealing. The preparation method of the high-nitrogen stainless steel spherical powder has the characteristics of high production efficiency, strong batch stability, high fine powder yield and the like; and the stainless steel spherical powder with high nitrogen content, good purity, strong mobility and smooth and clean surface can be easily prepared.

The invention provides a solidification method for preparing para-aramid by adopting dry jet-wet spinning. The method is characterized by comprising the following specific steps: extruding a PPTA-H2SO4 spinning solution from a spinneret plate; enabling liquid flow extruded from the spinneret plate to vertically pass through an air layer and feeding to a solidification bath; leading out through a godet wheel, so as to obtain a nascent fiber; and washing, winding and drying, so as to obtain a para-aramid fiber precursor, wherein the solidification bath is sulfuric acid solution and is formed by sulfuric acid and water; the mass fraction of the solidification bath is 2.0%-15.0%; and the temperature of the solidification bath is 1-12 DEG C. The fineness of the fiber can be significantly reduced under the condition of the solidification bath; the strength of the para-aramid fiber is improved; the apparent defects of the fiber can be reduced; and the fiber quality is improved, thus the stability of a spinning process and the quality of a fiber product can be effectively improved.

A process for preparing pseudo crystal granule reinforced magnesium group composite material, wherein the process for preparing AlCuFe pseudo crystal particles comprises the steps of, preparing powder, obtaining 20-100 um pseudo crystal particles after screening, with its composition being Al, Cu, Fe, after base stock melting, charging reinforced particles into alloy fondant for full mixing, depositing on the base stock along with the atomization alloy solid-liquid mixing at the atomizing action, finally the granule reinforced magnesium group composite material with even reinforced particle size distribution and fine base metal crystal grains can be prepared.

The invention relates to a solidification preparation method for aluminum oxide-based ternary nanometer eutectic/amorphous ceramic. A laser floating zone-melting directional solidification device is adopted for preparing an oxide ceramic material, and the heating capacity, relative moving capacity and combination with liquid metallic quenching phase of the laser floating zone-melting directional solidification device are utilized to quickly cool the melt and acquire the nanometer eutectic/amorphous ceramic in a wide solidification rate range. According to a melt falling liquid metal quenchingmethod based on a laser floating zone-melting directional solidification method provided by the invention, the ultrahigh cooling speed can be achieved at the moment of leaving the laser irradiation, namely, falling into the liquid metal for quenching, the cooling rate distribution spans at least four orders of magnitudes (10-10<6> micron/s), the solidification structure is abundant and the preparation for oxide nanometer eutectic/amorphous ceramic is easily realized.

The invention relates to a method for preparing a nickel-based abrasion resisting and corrosion resisting coating through ultrahigh-rate laser cladding, and belongs to the technical field of surface treatment. Through the methods that proper nickel-based powder is selected, the positions of powder gathering points and laser focus points are adjusted, and technology parameters are adjusted, the defect-free abrasion resisting and corrosion resisting coating with the good surface flatness and small thickness can be rapidly and accurately produced, ultrahigh-rate laser cladding is achieved, and the purposes of improving the production efficiency and saving the production cost are achieved.

The invention discloses a magnesium-aluminum alloy with continuous eutectic structure and a preparation method thereof, and the alloy is composed of a magnesium-aluminum alloy matrix and a continuouseutectic phase distributed at the grain edge of the matrix. The preparation method comprises the following steps that (1) nano-sized titanium powder and the magnesium-aluminum alloy powder are placedin a ball mill, and ball milling is conducted under protective atmosphere to obtain the mixed powder; and (2) the mixed powder is used as a raw material, and the magnesium-aluminum alloy with the continuous eutectic structure is prepared through selective laser melting under the protective atmosphere. According to the preparation method, the titanium is introduced in the magnesium-aluminum alloy preparation process, aluminum atoms in a molten pool are attracted to migrate, and eutectic reaction is generated on the edge of the crystal grain to generate the continuous eutectic phase; meanwhile,the characteristic that the selective laser melting solidification speed is high is utilized, the formation of the continuous eutectic phase is promoted while the content of a second phase Mg17Al12 isreduced, so that galvanic corrosion effect of the magnesium aluminum alloy is effectively weakened, and the corrosion resistance of the magnesium-aluminum alloy is improved; and meanwhile, better interface combination is achieved, so that the mechanical property of the magnesium-aluminum alloy is improved.

The invention provides a stainless steel welding rod improving vertical welding process performance. The stainless steel welding rod comprises a stainless steel core wire and a coating wrapping the surface of the stainless steel core wire, the coating is prepared from the following raw materials, in parts by weight, 30-40 parts of rutile, 3-8 parts of zircon quartz, 5-10 parts of feldspar, 10-18 parts of marble, 2-6 parts of fluorite, 2-8 parts of dolomite, 1-5 parts of magnesia, 1-5 parts of aluminum oxide, 5-10 parts of electrolytic manganese metal, 5-10 parts of chromium metal, 3-6 parts of ferrotitanium, 2-7 parts of iron powder, 1-2 parts of sodium alginate and 1-2 parts of microcrystalline cellulose. According to the stainless steel welding rod improving the vertical welding process performance, the excellent flat welding process performance of an acid coating stainless steel welding rod is reserved, meanwhile, by designing the coating of the welding rod, the welding rod melting rate is reduced, the slag forming number in unit time is reduced, the slag solidification rate is improved, vertical welding slag is stably solidified and does not flow downwards, and the vertical welding operability of the stainless steel welding rod is improved.

The invention discloses a reduced graphene oxide reinforced zinc-based medical material. The reduced graphene oxide reinforced zinc-based medical material is composed of a zinc base body and reduced graphene oxide, wherein the mass percentage of the reduced graphene oxide accounts for 0.05-0.2% by weight. On one hand, the reduced graphene oxide excellent in mechanical performance is adopted as a second phase reinforced zinc base body; and on the other hand, the characteristics that selective laser melting can achieve fast solidification and the reduced graphene oxide is excellent in heat-conducting property are utilized, and a tiny molten pool can be cooled rapidly, so that a fine and uniform structure is obtained; and the mechanical performance of the zinc base body is further enhanced through refined crystalline strengthening.

A soft alloy layer forming apparatus (10) includes a base metal support part (20) rotationally supporting a base metal (40) with a center axis (42) of an inner periphery of the base metal (40) being a rotation axis, and an arc generating unit (30) movable in a direction of the rotation axis of the inner periphery of the base metal (40), fixed at a predetermined distance from the inner peripheral face (41) of the base metal (40), and generating an arc (31) between itself and the base metal (40). While rotating the base metal (40) and maintaining the distance constant between the arc generating unit (30) and the inner peripheral face (41) of the base metal (40), a soft alloy member (50) is melted by the arc generating unit (30) to form a soft alloy layer (15) on the inner peripheral face (41) of the base metal (40). The invention also relates to a soft alloy layer forming method.

The invention discloses an efficient paint spraying chamber, which comprises a paint spraying room. A hollow space is fixedly arranged in the paint spraying room, an air inlet is fixedly formed in themiddle of the upper surface of the paint spraying room, an air exhaust pipe is fixedly arranged on the lower part of the surface of one side of the paint spraying room, an air exhaust space is fixedly arranged on the lower side in the paint spraying room and communicates with the air exhaust pipe, a placement plate is arranged in the middle of the bottom surface in the paint spraying room, vertical sliding rods are fixedly arranged on the two sides of the bottom surface of the paint spraying room correspondingly, the upper parts of rod bodies of the vertical sliding rods are slidably connected with vertical sliding blocks, and filter cotton is fixedly arranged on the upper part of the paint spraying room. In the efficient paint spraying chamber, automatic paint spraying is adopted, thus the operation efficiency is improved, meanwhile, spraying operation is conducted without labor, thus health damage to personnel is reduced, the air inlet is formed in the upper part, heating is conducted through an electric heating pipe, then filtering is conducted, thus the situation that air impurities fall on an object, and consequently smooth paint spraying is affected is reduced, and the solidification rate of a paint body is increased.

The invention relates to the technical field of metal casting, in particular to a casting device for an aluminum alloy thin-walled piece water-cooled metal shell mould. The casting device for the aluminum alloy thin-walled piece water-cooled metal shell mould comprises a metal shell mould, and is characterized in that the thermal capacity of the metal shell mould is reduced, the cooling speed of an aluminum alloy thin-walled piece in a mould filling process is reduced, and the mould filling capacity of a molten liquid in the device is improved by reducing the wall thickness of a casting mould;after the mould filling of the aluminum alloy thin-walled piece is completed, the metal shell mould is subjected to quick water cooling so as to improve the cooling speed of the molten liquid in a solidifying process, accelerate the solidifying rate of a casting, refine the structure of the aluminum alloy thin-walled piece and improve the mechanical properties; the casting device for the aluminumalloy thin-walled piece water-cooled metal shell mould solves the difficult problems that the mould filling of the aluminum alloy thin-walled piece is difficult to perform and the mechanical properties are poor; moreover, the metal shell mould can also be reused; the production efficiency is improved; and the manufacturing cost and the environmental pollution are reduced.

The invention discloses special polyurethane resin for soft basketball leather and a preparation method thereof, and relates to the technical field of chemical products and preparation methods thereof. The material is prepared from the following components in parts by weight: 5.37-5.98 parts of MDI, 70-100 parts of DMF, 12.33-13.70 parts of polyester polyol, 5.14-5.71 parts of polyether polyol, 3.01-3.42 parts of polycarbonate polyol, 0.77-1.08 parts of EG, 0.03-5 part of antioxidant, 0.003-3 part of phosphoric acid, 0.02-3 part of CATA, 0.03-5 part of malic acid, 0.05-7 part of CH3OH, 0.5-3 parts of HD-1, 0.5-5 parts of HD-2, and 2-4 parts of HD-3. According to the special polyurethane resin for the soft basketball leather and the preparation method of the special polyurethane resin, in the aspect of formula design, polyhydric alcohols are selected from high-molecular-weight polyester polyhydric alcohols and high-molecular-weight polyether polyhydric alcohols in a mixed mode, and dueto selection of the high-molecular-weight polyester polyhydric alcohols, a polyurethane soft segment is softer and softer and fuller in hand feeling; due to the introduction of the polyether polyol with large molecular weight, the hand feeling of the basketball leather is softer, and the leather is endowed with excellent surface wet and astringent touch feeling and better resilience.

The invention discloses a light alloy casting and rolling experimental device, belongs to the field of light alloy casting, and aims to solve the problem that an integrated forming device capable of realizing double-roller casting and rolling is lacked at present. According to the device, alloy heating and casting are combined into a whole, an alloy is subjected to heat preservation after being heated, a smelting furnace is directly pushed to the position above rollers, a rotating poking wheel of the smelting furnace is rotated, a smelting furnace cover is automatically opened, and the alloy melt is directly poured into a roller gap between the two rollers. The alloy melt is always in a heat preservation state before pouring, so that the heat loss of the alloy melt is reduced, the oxidation degree of the alloy is also reduced, and meanwhile, the safety of the whole operation process is relatively high. Cooling channels are arranged on the outer sides of the rollers, so that the roller adjusting difficulty is matched, and the roller machining difficulty is reduced; according to the device, the axes of the two rollers can be kept parallel and synchronously adjusted all the time, synchronous and opposite rotation of the two rollers is achieved through improvement of a transmission route, and the machining effect is guaranteed.