33results about How to "Fully refined grains" patented technology

The invention discloses low-temperature X80HD (High Density) large-deformation pipeline steel with great wall thickness and a production method thereof, belonging to the technical field of medium-thickness plate production and longitudinal submerged arc welded tube production. A steel plate comprises the following chemical components in percentage by mass: not less than 0.04% and not greater than 0.09% of C, not greater than 0.35% of Si, not less than 1.5% and not greater than 1.85% of Mn, not greater than 0.012% of P, not greater than 0.004% of S, not less than 0.02% and not greater than 0.05% of Nb, not less than 0.008% and not greater than 0.025% of Ti, not less than 0.10% and not greater than 0.50% of Ni, not less than 0.10% and not greater than 0.45% of Cr, not less than 0.10% and not greater than 0.30% of Cu, not less than 0.10% and not greater than 0.35% of Mo, not less than 0.020% and not greater than 0.070% of Alt, not greater than 0.0005% of B, not greater than 0.0050% of Ca, and the balance of Fe and inevitable impurities. A preparation method of the steel plate comprises the processes such as converter smelting, external refining, continuous casting, heating, controlled rolling, relaxation phase change control and quick cooling; a texture of the rolled steel plate is ferrite, bainite and a little M/A (Martensite/Austenite), wherein ferrite content is 60%-85%, and bainite and M/A content is 15%-40%. The obtained X80HD large-deformation pipeline steel has high strength and toughness, a high work-hardening index, high uniform ductility, a low yield ratio and good deformation resistance.

The invention relates to a low-crack sensitive pipe fitting steel plate used under a low temperature condition. The mechanical component (wt%) of the steel plate comprises 0.03-0.08 of C, 0.2-0.35 of Si, 0.9-1.6 of Mn, 0.02-0.04 of Al, 0.01-0.07 of Nb, 0.01-0.07 of V, 0.01-0.02 of Ti, less than or equal to 0.15% of Nb+V+Ti, less than or equal to 0.5 of Cr, less than or equal to 0.5 of Ni, less than or equal to 0.4 of Mo, less than or equal to 0.3 of Cu, less than or equal to 0.18 of Pcm and the balance Fe and inevitable impurities. The method sequentially comprises the steps of KR molten iron pretreatment, converter smelting, LF refining, RH vacuum degassing, 370-450 mm thickness continuous casting blank continuous casting, continuous casting blank capping slow cooling, continuous casting blank checking and cleaning, casting blank heating, high-pressure water descaling, rolling, cooling, straightening and offline tempering. The steel plate structure is controlled to be a single tempered bainite structure, the grain size is within the range of 3-6 microns, and the steel plate has very excellent low-temperature toughness and can meet the use requirements of X70 pipeline steel underthe low-temperature condition of -60 DEG C.

The invention relates to the technical field of special-shaped forged piece manufacturing technologies, in particular to a multi-step large-diameter casing ring forged piece and a manufacturing methodthereof. According to the multi-step large-diameter casing ring forged piece and the manufacturing method thereof, the casing ring forged piece is manufactured through processes of discharging, upsetting, punching, mandrel supporter reaming, inclining through breaking-off, forming die blanking, pre-rolling and rolling forming; the size distribution characteristic of a blank in the height direction meets the final forming requirements through upsetting, punching, mandrel supporter reaming, and forming die blanking; the large end of the blank is made to face downwards through a special structure, and rolling of the blank is ensured to be stable by loading from the position above a core roller die; the blank makes tight contact with the die by adjusting the size of the ring billet, and axialmoving of the blank is prevented; grains are refined by using high-temperature large deformation at the earlier stage, and the grains are kept to be unchanged by adopting low-temperature small deformation in the follow-up special-shaped blanking and forming process, so that the grains are fully refined; and finally, according to the manufacturing method of the multi-step large-diameter casing ring forged piece, rolling is stable, and the rolling precision of the forged piece can be well ensured.

The invention provides a method for manufacturing a tantalum target material. The method comprises the following steps: firstly, carrying out hot forging on a tantalum ingot and then carrying out first annealing on the hot-forged tantalum ingot to form a first tantalum target material billet; rolling the first tantalum target material billet to form a second tantalum target material billet; and carrying out second annealing on the second tantalum target material billet to obtain the tantalum target material. The tantalum target material formed according to the technical scheme has fine internal grains and uniform internal microstructure and thus the defects such as delamination inside the tantalum target material are effectively avoided, the sputtering rate of the tantalum target material and the quality of the formed tantalum film in the subsequent use process are improved.

The invention discloses a production method of a low-yield ratio high-strength medium-thick steel plate. The chemical composition mass percentage of the steel is C=0.06-0.09, Si=0.2-0.4, Mn=1.3-1.8, Al=0.02-0.05, Cr=0.30~0.40, Nb≤0.05, Ti=0.015~0.025, Mo≤0.30, B≤0.0010, P<0.02, S<0.005, CEQ<0.45, Pcm<0.22, the process steps include rolling and heat treatment. The method of the present invention is used for rolling low-yield ratio high-strength medium-thick steel plates, especially high-strength steel medium-thick plates with a yield strength of 550 MPa for construction machinery, and finally obtains tempered strips through quenching and tempering process or TMCP+tempering process. The plate with bainite structure has a yield strength of more than 550MPa, a tensile strength of more than 680MPa, a yield ratio of less than 0.9, an elongation after fracture of more than 17%, and a full-thickness V-notch Charpy impact energy of more than 140J at -20°C. . And excellent performance after welding.

The invention provides a tubular molybdenum target material preparation method. The method comprises the following steps: 1, molybdenum powder is compressed into a molybdenum tube blank; 2, a two-stage sintering process is adopted, and the molybdenum tube blank is subjected to sintering processing; 3, the molybdenum tube blank which is subjected to sintering processing is heated, and then is extruded and processed, and a tubular molybdenum target material is obtained after turning processing. According to the preparation method, cuttings are fewer, the production efficiency is high, the length of a molybdenum tube is adjustable, and the cost advantage is obvious; the production technological process is short, the metal loss is little, the comprehensive finished product rate is high, and the tubular molybdenum target material used for sputtering is conveniently, rapidly and largely produced.

The invention discloses a tungsten (molybdenum) alloy with double-size grains, a preparation method of the tungsten (molybdenum) alloy and a stirring tool for friction stir welding, and relates to the field of metal materials. The tungsten (molybdenum) alloy with the double-size grains is an alloy obtained by continuously preparing solid-solution-state powder prepared from tungsten (molybdenum) rhenium alloy powder, titanium powder and carbon powder; and in the tungsten (molybdenum) alloy with the double-size grains, the range of the small grains is controlled to range from 1.0 micrometer to 5.0 micrometers, the volume fraction of the small grains ranges from 40% to 70%, the size of the large grains is controlled to range from 20 micrometers to 100 micrometers, the ratio of the large grains ranges from 30% to 40%, and the average size of second-phase particles ranges from 20 nm to 50 nm. The tungsten (molybdenum) alloy with the double-size grains has the grains of two sizes, the high strength of the tungsten (molybdenum) alloy can be guaranteed through the thin and small equiaxed grains, channels can be provided for dislocation through the thick and large grains, the tungsten (molybdenum) alloy has the high tensile plasticity and toughness, and therefore the tungsten (molybdenum) alloy has the advantages of being high in strength and toughness at the same time.

The invention discloses a double-stand rolling method for rolling a super-thick steel plate by giving consideration to both plate shape and flaw detection performance, and belongs to the technical field of rolling of medium-thick plates. Through reasonably selecting billet type, a roughing mill adopts a mode of direct longitudinal rolling, instead of rolling through broadening, meanwhile, the thickness of steel plates at a controlled temperature is added 15-20mm based on that of a target thickness, so as to ensure that the overall rolling reduction at rough rolling phase reaches maximum, crystal grains in core part of the steel plates are fully refined to improve organizational performance of the core part; the overall rolling reduction at a finishing mill is 15-20mm, which is completed through three to five passes of rolling, the rolling reduction at the last pass is approximately 2-5mm, little rolling reduction functions to flatten the shape of the steel plates, thereby guaranteeing the shape of the steel plates.

The invention discloses a method for producing an iron-zinc alloy coated steel plate with the yield strength being equal to or higher than 220 MPa. The method comprises the steps that molten iron desulphurization, smelting through a converter and continuous casting are conducted, so that a billet is formed; hot rolling is conducted; rolling is conducted; cold rolling is conducted till the billet reaches the required thickness; continuous hot galvanizing is conducted; rapid cooling is conducted; aerial fog is used for cooling after zinc and iron are alloyed; finishing is conducted; oiling treatment is conducted; and sampling, performance testing and subsequence procedure treatment are conducted. According to the method for producing the iron-zinc alloy coated steel plate with the yield strength being equal to or higher than 220 MPa, on the premise that the yield strength ranges from 220 MPa to 260 MPa, the tensile strength ranges from 300 MPa to 380 MPa, and the elongation is equal to or higher than 43%, grains on the surface of a zinc-iron alloy coating are fine and are even in size distribution, the area ratio of holes in the surface of the coating is equal to or smaller than 5%, no microcrack exists on the surface, and the phenomena of pulverization and falling of the coating are unlikely to occur during stamping forming, namely the 90-degree V bending test grade reaches the level 2.

The invention discloses a microalloying method capable of improving performance of steel for large heat input welding. The specific flow process of the production method comprises a converter steelmaking process, an LF refining process and a continuous casting process; according to the kind and the adding sequence of a deoxidizing agent in the LF refining process, Mo, Mn, Si, Nb, Al, Ca, Mg and Ti are included; the Al is adopted for final deoxidation, Mo-Nb-Mg-Ti alloying is carried out, the dispersive action of the MgO on Al2O3 and Ti2O3 serves as the foundation, dispersed, rich and small refractory oxides are formed to serve as cores, and generation of acicular ferrite in austenitic crystalline grains is promoted; on the other hand, a certain amount of Mo and Nb improve toughness of the steel while the grains are refined, and forming of pro-eutectoid ferrite of the grain boundary is restrained; in addition, part of small inclusion particles and carbon nitrogen carry out pinning on the austenite grain boundary, through several-aspect joint action, heat affected zone grains are fully refined, and the toughness of the steel is obviously improved; and the method is simple in control and low in production cost, and the steel for large heat input welding can be subject to large-scale production in an industrialization manner.

The invention discloses a Mo-Nb-Ti-Mg steel smelting method for improving welding performance. The smelting method comprises the specific flowing processes of converter steelmaking, LF refining and continuous casting working procedures. Mo-Nb-Ti-Mg microalloyed steel chemically comprises, in percentage by mass, 0.06-0.08% of C, 1.25-1.60% of Mn, 0.010% or smaller of S, 0.025% or smaller of P, 0.20-0.40% of Si, 0.010-0.030% of Als, 0.060-0.080% of Mo, 0.010-0.020% of Ti, 0.002-0.005% of Mg, 0.020-0.035% of Nb and the balance of Fe and other unavoidable impurities. According to the Mo-Nb-Ti-Mg steel smelting method, Al final deoxidization is adopted for carrying out Mo-Nb-Ti-Mg microalloying, steel obdurability is obviously improved, control is simple, the production cost is low, and industrial mass production of steel for large heat input welding can be achieved.

The invention discloses a production method of a deep-drawing zinc-iron alloy plated steel plate with a compact surface plating structure. The production method comprises the steps of molten iron desulphurization, converter smelting, alloying, continuous casting, heating, rolling and alloying continuous hot galvanizing. In the alloying continuous hot galvanizing process, after galvanizing and zinc pot delivery are carried out, the cooling speed of an upstream section is controlled to be higher than or equal to 40 DEG C/s, and the cooling speed is controlled to be higher than or equal to 30 DEG C/s after alloying. The deep-drawing zinc-iron alloy plated steel plate in which zinc-iron alloy plating surface grains are fine, distribution is even in size, the plating structure is compact (the area ratio of surface holes is smaller than or equal to 5%), and the surface is free of obvious microcracks is obtained on the premise that the mechanical performance of the steel plate is guaranteed. The anti-pulverization performance of the zinc-iron alloy plated steel plate is improved, the 60-degree V bending test grade reaches the first level, and the phenomena of pulverization and falling of a plating are not likely to happen in the steel plate punching molding process; and accordingly the purposes of quality and production of zinc-iron alloy plated steel plate workpieces are achieved.

The invention relates to an aluminum alloy which comprises the following components including 0.9%-1.4% of iron, 0.5%-0.9% of magnesium, 0.2%-0.5% of manganese, 0.15%-0.3% of silver, 0.2%-0.3% of scandium, 0.3%-0.5% of yttrium and the balance aluminum. The invention further relates to a preparation method of the aluminum alloy. The invention also relates to a die casting which is made of the aluminum alloy.