335results about How to "Improve high temperature creep resistance" patented technology

The invention relates to an austenitic stainless steel, a steel tube thereof and a manufacturing method thereof, wherein the austenitic stainless steel and the stainless steel tube comprise the components by mass percent: 0.060-0.14% of C, more than 0 and less than or equal to 0.50% of Si, more than 0 and less than or equal to 1.00% of Mn, less than 0.040% of P, less than 0.015% of S, 17.00-20.00% of Cr, 8.00-11.00% of Ni, 2.50-4.00% of Cu, 0.30-0.60% of Nb, 0.15-0.50% of Mo, 0.15-0.50% of Co, 0.05-0.14% of N, 0.001-0.01% of B, the rest of Fe and unavoidable impurity. The manufacturing method of the steel tube comprises: smelting and pouring to form steel ingots or continuously cast bloom, processing bar material, preparing tubular billet and further processing the steel tube; the method comprises the steps: the heating temperature of processing the bar material is 1250-1270 DEG C, heating temperature of preparing the tubular billet is 1100-1220 DEG C, and the finished product solid solution temperature is 1120-1190 DEG C. The austenitic stainless steel tube has high temperature creep strength and corrosion resisting performance at the high temperature.

The present invention provides a coating inorganic fiber toughened MAX phase ceramic composite material and a preparation method thereof. The composite material adopts a MAX phase ceramic material as a matrix and adopts coating inorganic fibers as a toughening phase, wherein the coating inorganic fiber content is 0.5-90% (by volume), and the coating inorganic fibers are completely dispersed in the matrix and are inorganic fibers with the surface coated with the coating. Compared with the composite material in the prior art, the composite material of the present invention has the following characteristics that: the interface reaction between the inorganic fibers and the MAX phase ceramic can be effectively inhibited, the thermal expansion coefficient and elasticity modulus matching degree between the inorganic fibers and the MAX phase ceramic can be effective regulated, the effective improvement of the fracture toughness and the high temperature resistance of the MAX phase ceramic composite material can be achieved, the problems of high brittleness and insufficient use reliability of the MAX phase ceramic can be fundamentally solved, and the coating inorganic fiber toughened MAX phase ceramic composite material has potential application prospects in the high technology fields of civil use, aviation, aerospace, nuclear industry and the like, and is especially for the fission and fusion reactor nuclear power plant inner wall structure material.

A high-temp self-lubricating non-Pb Cu-base composition has a chemical formula: Ni+C+Sn+Zn+MX+Fe+Cu, where MX is chosen from BN, Si3N4, SiC, Al2O3, TiN, TiC and Cr3 C2 and C is graphite and carbon fibres. It has anti-oxidizing, anti-corrosion and high-temp anti-wear characteristics.

The invention relates to a combined composite brake disc, a preparation method and application, and belongs to the technical field of development of special brake discs. The combined composite brake disc comprises a friction disc body (1) and a connecting and supporting disc body (2). The friction disc body (1) is of a carbon-ceramic composite, and the connecting and supporting disc body (2) is of a gradient aluminum matrix composite compounded in a hot-pressing mode. The combined composite brake disc comprises the friction disc body (1) of the carbon-ceramic composite and the connecting and supporting disc body (2) of the gradient aluminum matrix composite. The friction disc body (1) of the carbon-ceramic composite and the connecting and supporting disc body (2) of the gradient aluminum matrix composite are connected into a whole through riveting. The brake disc designed in the invention is obviously longer than existing products in service life when being applied to high-speed trains.

The long fiber reinforced polypropylene / PPE alloy material has oriented fibers in the length over 4 mm and in netted configuration, and thus greatly raised shock resistance, rigidity, creeping resistance and size stability. What is more important is that the material may be mixed with many kinds of other material and thus has wide application range. The material may be prepared through powder soaking process, smelting soaking process, etc. The long fiber reinforced polypropylene / PPE alloy material of the present invention has excellent tensile, bending and anti-shocking performance, and may be used in manufacturing automobile part, pipe, valve part, electric tool, etc.

The invention relates to a heatproof stainless steel seamless steel pipe and a manufacture method of stainless steel and a seamless steel pipe. The quality percentage of a seamless steel pipe and stainless steel is: C is 0.03% to 0.08%, Si is greater than 0% and smaller than or equal to 0.50%, Mn is greater than 0% and smaller than or equal to 0.50%, P is smaller than 0.020%, S is smaller than 0.020%, Cr is 18.00% to 25.00%, Ni is 21.5% to 31%, Cu is 2.00% to 4.00%, N is 0.10% to 0.35%, Nb is 0.30% to 0.65%, W is 1.0% to 5.0%, Mo is greater than 0% and smaller than or equal to 0.40%, Co is 1.0% to 4.0%, B is 0.003% to 0.009%, and A1 is greater than 0%, and smaller than or equal to 0.04%. The manufacture method of the seamless steel pipe comprises the following steps: I, smelting: smelting austenitic stainless steel; II, pouring molten steel into steel ingots; III, pipe blanks machining: the forging steel ingots, and machining central through holes into pipe blanks; IV, pipe billets forming after extrusion: machining pipe blanks into pipe billets through methods of reaming and extruding; V, further machining of steel pipes: performing cold drawing and pulling and acid cleaning to the pipe billets repeatedly to obtain finished products. The heatproof stainless steel seamless steel pipe, provided by the invention, can be used in an ultra-supercritical thermal power generating unit boiler at a temperature of 700 DEG C.

The invention was involved in the preparation method of high intensity creep resistance magnesium alloy containing Ca and Si. The alloy consist of 3-9% Al, 0.1-1% Mn, 0.1-3% Ca,0.05-1.0% Zn, 0.05-1.0%Si, impurity which was composed with<0.005%Fe, <0.015% Cu and <0.002% Ni and the rest was Mg. Mg2Si phase and Al2Ca phase were generated at the same time by adding Ca and Si to intensify magnesium alloy. The shortage of the creep resistance of magnesium alloy was overcome compared with the single phase of Mg2Si or Al2Ca. The invention wasn't involved rare metal and the cost was low. The strength of extension under room temperature / high temperature, yield strength, extensibility and creep resistance were improved obviously.

The invention relates to a preparation method of an aluminum alloy sheet, particularly a preparation method of a nanoparticle-reinforced Al-Fe-Cr-Ti-Re heat-resistant aluminum alloy sheet. The invention aims to solve the problems of complex technique, high cost and multiple defects in the existing method for preparing the compacted large-size aluminum alloy sheet, and the problem of poor mechanical properties of the prepared Al-Fe-Cr-Ti-Re alloy sheet at room temperature and high temperature. The method comprises the following steps: proportioning materials, and preparing spherical alloy powder from the refined and degassed melt by a gas atomization method; and sequentially carrying out cool isostatic pressing, canning vacuum degassing, hot isostatic pressing, hot extrusion and rolling on the alloy powder to obtain the nanoparticle-reinforced Al-Fe-Cr-Ti-Re heat-resistant aluminum alloy sheet. The invention is mainly used for preparing the Al-Fe-Cr-Ti-Re heat-resistant aluminum alloy sheet.

A stainless heat-proof self-protecting flux-cored wire for a magnesium smelting reduction tank belongs to the technical field of materials processing engineering. A normal stainless steel band 304L or common carbon steel serves as a coating layer, and alloys in a powder core are rutile, sodium carbonate, feldspar, compound fluorides, chromium, nickel, manganese, molybdenum, chromium nitride, aluminium-magnesium alloy, misch metal and iron power. Compared with a conventional stainless steel welding rod, the stainless heat-proof self-protecting flux-cored wire has the advantages that higher welding current can be used; higher welding speed can be realized; the production efficiency is improved; and the labor intensity is lowered; c. Compared with a conventional stainless steel submerged-arc welding solid wire, the stainless heat-proof self-protecting flux-cored wire has the advantages that all-position welding can be realized; the heat input is small; the slag detachability is good; and the manufacturing technique is simpler. A welded joint formed by using the stainless heat-proof self-protecting flux-cored wire provided by the invention has favorable heat resistance, oxidation resistance, vulcanization and corrosion resistance and high-temperature creep resistance compared with welded joints formed by welding the stainless steel welding rod and the stainless steel solid wire.

Apparatus, which is suitable for being surrounded by molten glass, the apparatus having a shank which has at least one at least partially seamless tube consisting of an oxide dispersion-strengthened PGM material, the shank having at least one thickened portion on which an actuating device is arranged.

The invention relates to a plastic forming technique and a powder metallurgy technique and provides a tungsten carbide material which adopts Ni3Al as binder phase and a preparation method thereof. The tungsten carbide material adopts toughening intermetallic compound Ni3Al to substitute cobalt with traditional binder phase and contains the following components according to mass percentage: 86 to 95 percent of WC, 5 to 14 percent of toughening Ni3Al. The preparation method comprises the steps: ball grinding is carried out to the raw materials according to the percentages until the size of WC powder crystal grain is thinned to be less than 100nm; current rapid sintering method is adopted to form solidified ball grinding powder, and the conditions of current rapid sintering process are as follows: types of sintering current: square wave pulsed current or constant current; sintering pressure: 10MPa to 50MPa; sintering time: 2 to 8 minutes. The plastic forming technique, the powder metallurgy technique and the tungsten carbide material of the invention can not only save strategic material cobalt, reduce material cost, but also effectively improve the performance of high temperature resistant and corrosion resistant performance of the material and have good promotion and application prospect.

The invention relates the Cast-SHS preparation technology used for TiC / Ni3Al surface composite coating. The technology comprises the following steps: using Ni, Al, Ti, C powders as raw material, mixing them in proper proportion, pressing them to form precast block, drying, stick organic binding agent on the mould wall; preheating mould, pouring molten steel, and forming the TiC / Ni3Al intermetallic compound surface composite coating on the surface of steel. By adjusting the powder composition, intermetallic compound surface composite coatings which contain different ceramic enhancement phase contents can be obtained. The method possesses the advantages of simple technology, low cost, strong binding force and good combination property.

The invention relates to a composite high-temperature molybdenum disilicide-base material and a preparation method thereof. The method can prepare the composite high-temperature material under lower production cost, which has the highest room temperature toughness equivalent to that of high-temperature alloys, higher high temperature intensity, high temperature creep resistant performance and certain plastic processing performance; the substrate of the composite high-temperature material is a composite substrate composed of MoSi2 and Si3N4, wherein the average crystal grain size of the MoSi2 is smaller than 2 microns, and the average grain diameter of the Si3N4 particulates is smaller than 1 microns. The method adopts the following technical proposal: Mo2N powder or powder of Mo5Si3 or Mo3Si are used as initial powder to obtain composite powder Mo3Si-Mo5Si3-Si3N4 or Mo5Si3-MoSi2-Si3N4 after being processed by siliconization or nitridation-siliconization, the composite powder is further enhanced and mixed with materials such as Si powder, SiC powder and the like, and is pressing molded, and then a blank is sintered under the temperature of 1415 to 1550 DEG C, and finally the sintered blank is plastic deformed, thus obtaining a required dense article of the composite high-temperature material.

The invention relates to a composite ceramic fiber and a preparation method thereof. The composite ceramic fiber comprises the components of SiC (silicon carbide), MC and / or MB2, SiC which are evenly diffused and distributed, wherein M is one or more of Ti, Zr and Hf. The composite ceramic fiber uses a single or composite organic macromolecule precursor containing M, Si, C, H and a selectable B element as a raw material, a melt spinning technology is used, and the polybasic composite ceramic fiber is prepared from fiber stabilization and ceramic. The composite ceramic fiber disclosed by the invention has excellent mechanical and high-temperature-resistant antioxygenic properties, and can be used as a reinforcement body for preparing ceramic fiber reinforced composite materials.

A ferritic stainless steel having improved high temperature mechanical properties includes greater than 25 weight percent chromium, 0.75 up to 1.5 weight percent molybdenum, up to 0.05 weight percent carbon, and at least one of niobium, titanium, and tantalum, wherein the sum of the weight percentages of niobium, titanium, and tantalum satisfies the following equation: 0.4<=(% Nb+% Ti+½(% Ta))<=1. The coefficient of thermal expansion of the ferritic stainless steel is within 25 percent of the CTE of stabilized zirconia between 20° C. (68° F.) and 1000° C. (1832° F.), and the steel exhibits at least one creep property selected from creep rupture strength of at least 1000 psi at 900° C. (1652° F.), time to 1% creep strain of at least 100 hours at 900° C. (1652° F.) under load of 1000 psi, and time to 2% creep strain of at least 200 hours at 900° C. (1652° F.) under load of 1000 psi. The steel is particularly suited for high temperature applications including, but not limited to, current collecting interconnects in solid oxide fuel cells, furnace hardware, equipment for the chemical process, petrochemical, electrical power generation, and pollution control industries, and equipment for handling molten copper and other molten metals.

The invention relates to a die-casting heat resistant magnesium alloy and a preparation method thereof, pertaining to the metal material technology field. The components and weight percentage thereof of the alloy are as follows: 1.5 to 6.0 percent of Sm, 0 to 3.0 percent of Nd, 0 to 2.5 percent of Ca, 0.1 to 2.0 percent of Zn, 0.2 to 0.8 percent of Zr, lower than 0.02 percent of impurity elements, and the rest is Mg. The preparation method of the alloy comprises the following steps: the materials are weighed, and industrial pure Mg is heated under the protection of the mixed gas of N2 and SF6; after Mg is wholly melted, industrial pure Zn, industrial pure Ca and Mg-Sm interalloy and Mg-Nd interalloy are added at the temperature of 650 to 680 DEG C, Mg-Zr interalloy is added at the temperature of 760 DEG C, the temperature is maintained and the mixture is stirred, then the temperature is increased to 780 to 800 DEG C and maintained, after that the temperature is adjusted to 750 to 760 DEG C for refining and maintained for 30min, and when the Mg liquid is cooled to 680 to 700 DEG C, the mixture carries out die casting. The alloy of the invention has excellent tensile strength, yield strength and elongation and creep resistance simultaneously, and has good die-casting performance.

The invention discloses a high-strength wear-resisting heat-resisting aluminium alloy material and a preparation process thereof. The material comprises, by weight, 4.0-6.5% of copper, 0.06-0.4% of titanium, 0.08-0.6% of manganese, 0.03-0.4% of antimony, 0.4-0.6% of nickel, 1.2-1.8% of cobalt, 0.2-0.3% of zirconium, 0.2-1.8% of rare earth and the balance aluminum. During preparation of the material, a special heat treatment process is used. The material has the advantages of being capable of improving the mechanical strength, the abrasive resistance and the high-temperature deformation resistance of an aluminium alloy simultaneously, the material can be used for cast members which are required to bear a certain high temperature and have high mechanical performance requirements, and a new field of application of the aluminium alloy material is developed.

The present invention relates to a multicomponent heat-resisting magnesium alloy which can be extensively used in engine component of car, minibus and motorcycle and its casting process. Its composition formula includes (wt%) Al 5-7, Zn 5-1.0, Si 0.6-1.5, Sb 0.4-0.7, RE 0.1-0.3, Be 0.002%, and impurity elements Fe is less than 0.005%, Cu is less than 0.015 % and Ni is less than 0.002% and the rest is Mg. Its casting process is characterized by that under the condition of smelting with flux or gas protection completely melting industrial pure magnesium, then respectively adding alloy elements of Al, Zn, Si, Sb, RE and Be in the form of industrial pure aluminium, industrial pure zinc, Al-Si intermediate alloy, industrial pure stibium, Mg-RE intermediate alloy and Al-Be intermediate alloy, dissolving them completely, uniformly stirring, refining and casting. The microstructure of the invented cast alloy is obviously refined, and the room-temp. and high-temp. tensile strength, yield strength and percentage elongation of the alloy also can be raised.

The invention discloses a high-temperature-resistant lightweight heat-insulating material with a dual pore structure and a preparation method thereof. The preparation method comprises the following steps: with alumina, silica and aluminosilicate powder as raw materials, adding a molding aid and a pore forming agent into the raw materials and carrying out uniform mixing under stirring; and then subjecting a mixture obtained in the previous step to extrusion molding and then to sintering so as to obtain the high-temperature-resistant lightweight heat-insulating material with the dual pore structure composed of macroscopic through hole channels and micropores, wherein a ratio of the total volume of through holes to the total volume of the micropores is 0.5-25: 1. According to the invention, through synergism of proper volumes of a micropore structure and the macroscopic through hole channels, the prepared material has improved energy conservation effect and thermal shock resistance, and substantially enhanced strength and high-temperature creep resistance while high temperature performance of the material is guaranteed.

The invention relates to a preparation method of a bicontinuous-phase alumina / epoxy resin composite material, belonging to the technical field of composite materials. The method comprises the following steps: carrying out compression molding on Al2O3 powder with different particle sizes under different pressures, and sintering at different temperatures under normal pressure for holding time to obtain the porous Al2O3 ceramic with adjustable porosity and pore size; and after carrying out surface modification, standing the preheated porous Al2O3 ceramic in a mixed solution composed of an epoxy resin, an accelerator and a curing agent for some time, and carrying out solidifying formation to obtain the bicontinuous-phase alumina / epoxy resin composite material. The porosity of the porous alumina ceramic is regulated by controlling the content of the foaming agent and the volume density of the green compact, thereby regulating the volume percent of the alumina reinforcement phase in the composite material. The alumina phase in the composite material is a continuous phase, can greatly enhance the high / low-temperature mechanical properties, thermal conductivity and high-temperature creep resistance of the alumina / epoxy composite material, and provides a new idea for researching and developing high-performance epoxy resin composite materials.

The invention discloses a method and a device for forming magnesium alloy formed parts with excellent high-temperature mechanical property. The device mainly comprises a die, a laser, a thermal sensor, a miniature heater and the like. The method includes: heating magnesium alloy to 120-150 DEG C to realize high-speed contact molding according to the laser peening quick-forming technology which utilizes dynamic strain ageing reinforcement, heat forming and high-pressure strain rate of thermal laser peening, placing magnesium alloy plates on a die in a work cavity, attaching energy converters on the magnesium alloy plates, vacuumizing the work cavity, and realizing high-speed contact molding of the magnesium alloy plates by the thermal laser peening process through the miniature heater and the laser. Dislocation anchoring effect and nano precipitates are formed in formed parts by the thermal laser peening technology, so that the magnesium alloy formed parts have excellent high-temperature mechanical property such as high-temperature creep resistance, high-temperature strength and the like, thermal high-strain-rate forming of the magnesium alloy plates is realized, and forming performance and efficiency of the magnesium alloy are improved.

The invention relates to a preparation method of a mullite fiber / epoxy resin composite material and belongs to the technical field of composite materials. According to the preparation method, first, a sol-gel method is adopted for obtaining 3Al2O3.2SiO2 type mullite precursor powder, the obtained powder is subjected to compression molding forming under different pressure, and then blanks of different porosities are obtained; the obtained blanks are subjected to high-temperature sintering to obtain porous mullite ceramics of different porosities, wherein mullite is in a fiber shape and is overlapped mutually; the preheated porous mullite ceramics are put into a mixed solution of epoxy resin, a promoter and a solidifying agent to be kept for certain time, and the mullite fiber / epoxy resin composite material is obtained after solidifying. By control over the volume and density of the porous material, the volume fraction of the mullite fibers in the composite material is regulated; in addition, the mullite fibers in the composite material are in a continuous phase, in this way, the high-temperature and low-temperature mechanical properties and high-temperature creep resistance of the composite material can be substantially improved, and the thermal conductivity of the composite material can be greatly increased.

The invention discloses an anti-creep rare earth magnesium alloy and a preparation method thereof. The magnesium alloy consists of the following components in percentage by mass: 2-6% of Sm, 0.2-2.2% of Nd, 0.5-3.5% of Gd, 1.2-2.4% of Zr, 0.2-1.5% of Ca, 0.2-1.4% of Ag, 0.3-1.1% of Sb, 0.2-1.3% of Er, and the balance of Mg and inevitable impurities. The anti-creep rare earth magnesium alloy is higher in room temperature and high-temperature mechanical performance; under the creep condition of 250 DEG C / 100 MPa, the creep quantity is decreased to 0.15%, and the stable creep speed is decreased to 5.14*10-9s-1; and the magnesium alloy is excellent in high-temperature creep resistance, lower in total content of rare earth, low in cost, uniform in microscope structure and suitable for the engineering field having higher high-temperature creep resistance requirement on the magnesium alloy.

The invention discloses a polypropylene modified material for an expansion water tank of an automobile and a preparation method thereof and belongs to the technical field of auto part manufacturing. The polypropylene modified material for the expansion water tank for the automobile comprises the following components in percentage by weight: 75-85 percent of propylene-ethylene block polypropylene copolymer, 10-20 percent of linear low density polyethylene (LLDPE) resin, 2-5 percent of ethylene propylene diene monomer (EPDM), 0.1-0.5 percent of nucleating agent and 0.1-0.5 percent of antioxidant. After being mixed according to the proportion, the materials are extruded and granulated by a double screw extruder under the conditions that the processing temperature is 210-240 DEG C, and the screw speed is 210-240 revolutions / minute. The polypropylene modified material has the beneficial effects that polypropylene is modified by the reasonable components according to the mixing proportion, so that the material has higher low-temperature impact strength and higher high-temperature creep resistance; and meanwhile, the hot plate welding performance of the material is improved, the material transparency is improved, and the production processing requirements and the use requirements of the expansion water tank for the automobile are completely satisfied.

A ferritic stainless steel having improved high temperature mechanical properties includes greater than 25 weight percent chromium, 0.75 up to 1.5 weight percent molybdenum, up to 0.05 weight percent carbon, and at least one of niobium, titanium, and tantalum, wherein the sum of the weight percentages of niobium, titanium, and tantalum satisfies the following equation: 0.4<=(% Nb+% Ti+½(% Ta))<=1. The coefficient of thermal expansion of the ferritic stainless steel is within 25 percent of the CTE of stabilized zirconia between 20° C. (68° F.) and 1000° C. (1832° F.), and the steel exhibits at least one creep property selected from creep rupture strength of at least 1000 psi at 900° C. (1652° F.), time to 1% creep strain of at least 100 hours at 900° C. (1652° F.) under load of 1000 psi, and time to 2% creep strain of at least 200 hours at 900° C. (1652° F.) under load of 1000 psi. The steel is particularly suited for high temperature applications including, but not limited to, current collecting interconnects in solid oxide fuel cells, furnace hardware, equipment for the chemical process, petrochemical, electrical power generation, and pollution control industries, and equipment for handling molten copper and other molten metals.

The invention discloses a wear-resisting and high-hardness flux core wire. The wear-resisting and high-hardness flux core wire is composed of a flux core and a low-carbon cold-rolling steel tape sheath wrapped on the outer side of the flux core. The flux core comprises, by weight, 20-25 parts of low-carbon ferrochromium, 1.5-3 parts of titanium powder, 1-2 parts of nickel powder, 5-8 parts of calcium-silicon alloys, 2-4 parts of magnesium-aluminum alloys, 3-5 parts of electrolytic manganese, 1-2 parts of ferromolybdenum, 2.5-4 parts of ferroniobium, 1-2 parts of ferrovanadium, 3-5 parts of rare earth iron alloys, 3-5 parts of carbonate, 3-4 parts of graphite, 120-150 parts of iron powder, 0.5-1.5 parts of tungsten powder and 2-4 parts of calcium fluoride. The wear-resisting and high-hardness flux core wire has good welding performance, deposited metal tissue is compact, air holes and cracks are avoided, combination with base metal is good, performance is stable, and deposited metal has good wear resistance, corrosion resistance, high hardness and other performance.

The invention provides a nickel-based alloy. The nickel-based alloy comprises the following components including, by weight, 18.0%-23.5% of cobalt, 10%-15% of chromium, 2.5%-3.5% of aluminum, 2.0%-4.0% of titanium, 0.1%-2.0% of niobium, 1.0%-3.0% of tantalum, 0%-2.5% of tungsten, 4%-5.5% of molybdenum, 0.03%-0.1% of zirconium, 0%-1.0% of hafnium, 0.01%-0.1% of carbon, 0.01%-0.1% of boron and the balance nickel. According to the nickel-based alloy, the content of alloy elements in the high-temperature alloy is adjusted systematically, so that it is ensured that the alloy has good mechanical properties, and the alloy has good tissue stability at high temperature.

The invention discloses a high-temperature-resistant and creep-resistant polyethylene heat shrinkage film and a film-blowing process thereof, and belongs to the field of plastic films. The film is prepared by co-extruding an inner layer, a middle layer and an outer layer, wherein the raw materials of both the inner layer and the outer layer comprise bimodal linear low-density polyethylene, metallocene polyethylene and low-pressure high-density polyethylene, and the raw materials of the middle layer comprise metallocene polyethylene and high-pressure low-density polyethylene. The polyethylene heat shrinkage film provided by the invention is excellent in high-temperature resistance and creep resistance; under the environment of 40 DEG C or above, when 50 MPa tensile stress is applied to the film for 120 hours, the creep rate of the film is 0.2% or below, the lateral shrinkage of the film is 15-30%, the longitudinal shrinkage of the film is 55-80%, the lateral tensile strength is 50 mpa or above and the longitudinal tensile strength is 52 mpa or above. In addition, the raw materials are mixed according to appropriate proportion; in the preparation process, the melt viscosity is greatly reduced when being compared with the prior art that only linear low-density polyethylene is adopted, and the energy consumption is reduced by 35% or above when being compared with the prior art that only linear low-density polyethylene is adopted.