57results about How to "Prevent mixed crystals" patented technology

The invention relates to steel for bottle caps and a preparation method thereof, especially to steel for hard tinplate bottle caps and a production method thereof. The invention mainly solves the technical problems of unstable rolling, high hole ratio for pickling-rolling and poor surface quality of each process during pickling-rolling production of present steel for bottle caps. The technical scheme provided by the invention is as follows: the steel for hard tinplate bottle caps comprises the following chemical components of: by weight, 0.045-0.088% of C, Si being less than or equal to 0.1%, 0.30-0.50% of Mn, P being less than or equal to 0.020%, S being less than or equal to 0.020%, 0.010-0.060% of Alt, N being less than or equal to 0.0060%, and the balance Fe and some unavoidable impurity elements. The production method comprises four steps of steeling-making, hot rolling, pickling-rolling and continuous annealing, and is characterized in that hot rolling is controlled in the way: tapping temperature is 1200+/-30 DEG C, finishing temperature is 880+/-30 DEG C and coiling temperature is 580+/-30 DEG C; cooling mode is forepart cooling; pickling-rolling and continuous annealing are controlled in the way: RTF section temperature is 610+/-15 DEG C and SF section temperature is 610+/-15 DEG C. Hardness of the obtained tinplate finished product is HR30T63+/-3. The production method provided by the invention is mainly used for production of steel for bottle caps.

The invention provides an X52 pipeline steel and a production method thereof. The X52 pipeline steel comprises the following chemical components: 0.070-0.090wt% of C, 0.15-0.30wt% of Si, 1.10-1.30wt% of Mn, 0.006wt% or more of S, 0.020wt% or more of P, 0.020-0.040wt% of Nb, 0.010-0.020wt% of Ti, 0.008wt% or more of N, 0.010-0.040wt% of Als, the rest of Fe and unavoidable impurities. After heating and descaling, rough rolling and finish rolling are performed on the same dual-frame compact Steckel mill continuously; through delayed rolling control in rolling process, the enhancement function of microalloy elements such as Nb and V added to the steel are given a full play, thereby obtaining superfine and uniform tissue, effectively preventing the occurrence of mixed crystal, and greatly improving the strength and toughness of the X52 pipeline steel. The X52 pipeline steel produced with the method belongs to high-technology product with high additional value, thus the economical benefit is significant.

The invention provides X60 pipe line steel and a preparation method thereof. The X60 pipe line steel comprises the following chemical components in percentage by weight: 0.060 to 0.080 percent of C, 0.15 to 0.30 percent of Si, 1.35 to 1.55 percent of Mn, less than or equal to 0.006 percent of S, less than or equal to 0.020 percent of P, 0.035 to 0.055 percent of Nb, 0.035 to 0.055 percent of V, 0.010 to 0.025 percent of Ti, less than or equal to 0.008 percent of N, 0.010 to 0.040 percent of Als, and the balance of Fe and inevitable impurities. After heating and descaling, rough rolling and finish rolling are continuously completed on the same steckel mill, the reinforcing effect of Nb, V and other microalloyed elements added in the steel can be sufficiently played by delay controlled rolling in the rolling process, micro-uniform tissues can be obtained, occurrence of mixed crystal can be effectively prevented, and the strength and toughness of the X60 pipe line steel can be greatly improved. The produced X60 pipe line steel belongs to the product with high technology content and high additional value, and has remarkable economic benefit.

The invention provides X65 pipe line steel and a production method thereof. The X65 pipe line steel comprises the following chemical components in percentage by weight: 0.055 to 0.090 percent of C, 0.15 to 0.35 percent of Si, 1.50 to 1.65 percent of Mn, less than or equal to 0.005 percent of S, less than or equal to 0.020 percent of P, 0.040 to 0.055 percent of Nb, 0.040 to 0.070 percent of V, 0.010 to 0.025 percent of Ti, less than or equal to 0.008 percent of N, 0.005 to 0.060 percent of Als, and the balance Fe and inevitable impurities. After heating and descaling, rough rolling and finish rolling are continuously completed on the same double-rack compact steckel mill, the reinforcing effect of Nb, V and other microalloyed elements added in the steel can be sufficiently played by delay controlled rolling in the rolling process, a micro-uniform tissue can be obtained, the occurrence of mixed crystals can be effectively prevented, and the strength and toughness of the X65 pipe line steel can be greatly improved. The produced X65 pipe line steel belongs to the product with high technology content and high additional value, and has remarkable economic benefit.

The invention discloses a low-yield-ratio high-toughness TMCP type bridge steel plate and a production method thereof. The steel comprises the following chemical components in percentage by weight of0.07 to 0.12% of C, 0.11 to 0.18% of Si, 1.42 to 1.52% of Mn, 0.008 to 0.015% of P, 0.002 to 0.010% of S, 0.08 to 0.16% of Cr, 0.012 to 0.018% of Nb, 0.008 to 0.016% of Ti, 0.020 to 0.050% of Alt, 0.002 to 0.005% of N, the balance iron and impurities and 0.350 to 0.369% of carbon equivalent. According to the production method, a continuous casting billet is subjected to heating, controlled rollingincluding recrystallization zone rolling, temperature waiting and non-recrystallization zone rolling and controlled cooling including ferrite zone cooling, temperature waiting and bainite zone cooling, and the bridge steel plate is manufactured. The obtained bridge steel plate is low in yield ratio, high in toughness and excellent in welding performance.

A machining technology for the aged 18(Ni)-series non-Co martensite steel with high strength and toughness includes hot working, cold working by direct cold rolling or machining without solution treatment, ageing at 400-600 deg.C for 0.5-3 hrs, and air or water cooling. Its advantages are short period and simplified heat treatment.

The invention discloses a hot working process of a GH4738 nickel-based superalloy. The process comprises the following steps that A, the GH4738 nickel-based superalloy is taken as a raw material, and is smelted by adopting a vacuum induction melting (VIM) process and a vacuum consumable remelting (VAR) process in sequence to obtain a vacuum consumable ingot; B, the vacuum consumable ingot is subjected to homogenization treatment and cogging forging treatment, and a GH4738 alloy bar blank is obtained; C, the GH4738 alloy bar blank is put into a gas furnace to be heated along with the furnace, flat anvil upsetting is conducted through a forging hammer after heat preservation, and a GH4738 alloy disc forge piece is obtained; and D, the GH4738 alloy disc forge piece is sequentially subjected to solution treatment, stabilizing treatment and secondary aging treatment, and the GH4738 nickel-based high-temperature alloy uniform in grain size and excellent in high-temperature erosion performance is obtained. According to the hot working process, the phenomena of mixed crystals, coarse crystals and the like in a GH4738 high-temperature alloy deformation structure can be avoided, the overall hardness and high-temperature erosion performance of a final forge piece are improved, and meanwhile the yield of the forge piece is increased.

The invention relates to a high-intensity anti-atmosphere corrosion steel and a production method thereof and belongs to the field of metallurgy. The technical problem needed to be solved by the invention is to provide a V-Ti-N-Nb micro-alloy high-intensity anti-atmosphere corrosion steel which has an easily-controlled hot rolling technique and has an obvious yield point. The weight percentages of the chemical components of the high-intensity anti-atmosphere corrosion steel of the invention are: equal to or less than 0.12 percent of C, equal to or less than 0.75 percent of Si, equal to or less than 1.50 percent of Mn, equal to or less than 0.025 percent of P, equal to or less than 0.008 percent of S, 0.30 to 1.25 percent of Cr, 0.12 to 0.65 percent of Ni, 0.20 to 0.55 percent of Cu, 0.006 to 0.02 percent of Ti, 0.04 to 0.09 percent of V, 0.01 to 0.02 percent of N, 0.015 to 0.03 percent of Nb and the rest is Fe and unavoidable impurities. The high-intensity anti-atmosphere corrosion steel of the invention can be used for producing the mechanical devices and parts that need to be exposed in the air.

The invention provides a production method for second gears of automatic automotive transmissions. According to the production method, pre-forging blanks are subjected to cold extrusion after being produced by isothermal forging. The production method is characterized in that the inclination of the inner walls of modified grooves of the pre-forging blanks is 2-4 degrees larger than that of finish-forging blanks. Products produced by the production method are high in accuracy and low oxidizing, good internal structure of metal is realized, crystal grains are fine, and poor textures such as coarse crystals and mixed crystals are avoided; equipment as needed is low in tonnage and small in forming fore, filling of tooth profile is easy, unit pressure borne by molds is remarkably reduced, and service life of the molds are quite long; product hardness reaches HB130-150, and metal structure reaches the second level; the tooth profile is fully filled and does not deform during heat treatment after cold extrusion forming.

The invention relates to Q420-grade anti-seismic steel and a method for producing the Q420-grade anti-seismic steel by virtue of a steckel mill, and belongs to the technical field of metal material processing and forming. The Q420-grade anti-seismic steel consists of the following components: C, Si, Mn, S, P, Nb, V, Ti, N, Als and the balance of Fe and inevitable impurities. A Q420-grade anti-seismic steel sheet which is high in strength and low in yield ratio can be prepared by heating a slab, spraying water and removing phosphorous, continuously completing rough rolling and finish rolling on a same dual-stand compact steckel mill, cooling a steel sheet obtained from finish rolling by virtue of a coiling machine and naturally air-cooling to room temperature. By adding such micro-alloying elements as Nb and V to the Q420-grade anti-seismic steel, the strength and the tenacity of the Q420-grade anti-seismic steel sheet are effectively improved; in the process of producing the Q420-grade anti-seismic steel sheet, the method disclosed by the invention fully explores the potential of the dual-stand compact steckel mill of kunming Iron and Steel; the variety of plate and strip products is expanded and product structure is optimized.

The invention discloses a deformation high-temperature alloy blade forged piece and a precision forging method thereof. The precision forging method comprises the following steps that S1, a high-temperature alloy bar material is subjected to heat preservation for 8-60 min at the temperature of 950-1150 DEG C, and extrusion is conducted; S2, heating is conducted for 8-60 min at the temperature of 910-1060 DEG C, and head upsetting is conducted; S3, heating is conducted for 6-60 min at the temperature of 910-1060 DEG C, and pre-forging is conducted; and S4, heating is conducted for 4-60 min at the temperature of 910-1060 DEG C, finish forging is conducted, and a finish forged piece is obtained. The invention further discloses the deformation high-temperature alloy blade forged piece obtainedthrough the precision forging method. The precision forging method and the deformation high-temperature alloy blade forged piece have the beneficial effects that precision forging forming of the blade forged piece based on a novel nickel-based high-temperature alloy GH4169D material is achieved, an obtained GH4169D alloy blade can meet the requirements for the shape and size of an aero-engine blade and for the performance at the high temperature of 650 DEG C to 750 DEG C, and the requirement for the temperature bearing capacity of a blade material due to the fact that the performance and theuse requirement of an aero-engine are continuously improved is met.

The invention belongs to the technical field of metallurgical processes and equipment, and relates to a continuous casting and rolling production line capable of avoiding ferrite rolling mixed crystals and a control method. The invention discloses a continuous casting and rolling production line capable of avoiding ferrite rolling mixed crystals. The continuous casting and rolling production line comprises a continuous casting machine, a roughing rolling unit, an intermediate billet heat preservation device, a finishing rolling unit, an after-rolling cooling device, a high-speed flying shear and a coiling unit which are sequentially arranged along a rolling line. A rolled piece heating device, a descaling device, an accident handling device, an intermediate billet cooling device and the like can be arranged on the production line according to needs. The intermediate billet heat preservation device is arranged in front of a finishing mill group, the temperature of the intermediate billet when reaching an inlet of the intermediate billet heat preservation device is controlled to be below the ferrite phase change temperature, the heating temperature of the intermediate billet heat preservation device is controlled, the intermediate billet is subjected to heat preservation or slow cooling in the device, the austenite-ferrite phase change time is prolonged, and the production efficiency is improved. And phase change is fully carried out, mixed crystals caused by double-phase rolling are avoided, and the structure property uniformity of a ferrite rolled product is improved.

The invention discloses a hot working method of a high-performance small-distortion carburized outer ring, relates to the technical field of hot working methods, and solves the technical problems of complex manufacturing process, non-uniform carburized layer depth and poor quality consistency of the existing outer ring, and is suitable for forging and heat treatment of the outer ring made of 17Cr2Ni2MoVNb steel, the diameter of the outer ring is 150-200 mm, and the wall thickness of the outer ring is 8-10 mm. The hot working method comprises the following steps of constructing a true stress-strain curve and a hot working diagram, forging, normalizing and tempering at a high temperature, roughly machining, thermal refining, roughly machining a tooth shape and the like, performing gas/liquid composite carburizing and tempering at a high temperature, quenching and tempering at a low temperature. According to the hot working method, the ovality of the carburized and quenched outer ring is controlled to be less than or equal to 0.15 mm, the grain size is greater than or equal to 8.5 grades, and the rotating bending fatigue strength of a furnace sample is greater than or equal to 1000 MPa; and the part has high performance, meanwhile, only small heat treatment deformation exists, and good industrial application value is achieved.

The invention discloses a simple preparation method for explosive solvate. The simple preparation method comprises the following key steps: under a normal temperature condition, placing explosive rawmaterials and a solvent in a sealed environment separately, slowly volatilizing the solvent through vacuuming, generating solvent steam of low pressure and low concentration, enabling the solvent steam to freely diffuse to the surface of explosive crystal, and inducing a gas-solid reaction, thereby obtaining the explosive solvate. The explosive solvate prepared by using the method is of a micro crystal cluster structure and has relatively low temperature, and a primary template can be provided for later explosive micro structure regulation and control. The method has the characteristics of being simple in process procedure, gentle in experiment condition, rapid and efficient in preparation, free of pollution, low in cost, and the like, and is particularly applicable to on-scale preparation.

The invention discloses low-silicon microalloyed high-temperature carburized gear steel and a manufacturing method thereof. The manufacturing method includes the steps that about 20% of scrap steel isadded into a converter, then molten iron is added for smelting, final steel tapping control targets are that C is larger than or equal to 0.08% and P is smaller than or equal to 0.015%, sliding plateslag stopping operation is conducted in the steel tapping process, and discharged slag is reduced; and alloying is started about 90 seconds after tapping is started, and ferro-aluminum, carbon powder, an alloy and lime are added in sequence. According to the low-silicon microalloyed high-temperature carburized gear steel and the manufacturing method thereof, enrichment of inclusions at the innerside of a gate is greatly reduced, steady-state control over a stopper curve in the casting process is achieved, involving of large-size inclusions due to the fact that the stopper curve suddenly fluctuates is avoided, continuous casting production of at least six furnaces can be achieved, and meanwhile the service fatigue life of a gear is remarkably prolonged; and abnormal growth of austenite grains is hindered, and the austenite grain coarsening temperature of the gear steel is increased, so that the effects of preventing mixed grains and coarse grains of the austenite grains of the gear steel after high carburizing temperature are achieved.

The invention discloses a deformation high-temperature alloy blade forged piece and a die forging method thereof. The die forging method comprises the following steps: extrusion heating, specifically,the heating temperature is 950-1100 DEG C, and the heat preservation time is 10-60 min; extrusion forming; finish forging heating, specifically, the heating temperature is 910-1060 DEG C, and the heat preservation time is 5-60 min; and finish forging for obtaining a finish forged piece. The provided method can effectively realize the consistency of the quality of the forged pieces, increases thequalification rate of the finished forge piece and improve the quality of the finished forge piece. The invention further discloses a deformation high-temperature alloy blade forged piece obtained through the die forging method. The deformation high-temperature alloy blade forged piece has the advantages that the surface is free of cracks, and the internal structure meets the design requirement, the requirements for the shape and size of an aero-engine blade and for the performance at the high temperature of 650 DEG C to 750 DEG C can be met, and the requirement for the temperature bearing capacity of a blade material due to the fact that the performance and the use requirement of an aero-engine are continuously improved is met.