36 results about "Flexural fatigue" patented technology

The invention discloses a forming device and a forming method of a high-temperature-resistant low-temperature-resistant high-toughness cable. According to the invention, based on a double-substrate synergistic system of hydrogenated nitrile rubber and polyether type thermoplastic polyurethane, and in combination with a dynamic vulcanization crosslinking technology, the cable keeps excellent flexibility and tear resistance in a wide temperature range of-60 DEG C to 125 DEG C. A three-dimensional reinforced network of nano silicon dioxide and carbon nanotubes is directionally dispersed in a matrix, and mechanical support of aramid short fibers is matched, so that the cable is endowed with bending fatigue resistance, the durability of the drag chain cable in a high-frequency torsion scene of an oil platform exceeds 30 million cycles is realized, and the service life of the drag chain cable is prolonged. The problem of breakage caused by low-temperature embrittlement and high-temperature softening of a traditional cable is fundamentally solved, the synergistic effect of the perfluoropolyether surface modifier and the composite anti-aging system enables the cable to form a stable protective layer in strong acid, strong alkali, salt mist and oil stain environments, and chemical corrosion and ultraviolet irradiation are effectively resisted.

The invention discloses high-toughness ultrathin flexible glass and a preparation method thereof, and relates to the technical field of glass manufacturing. The ultrathin flexible glass is prepared from the following raw materials: silicon dioxide, aluminum oxide, lithium oxide, sodium oxide, magnesium oxide, a modified nano reinforced phase, a high-temperature melting regulator and cerium dioxide. The modified nano reinforced phase is prepared by the following steps: pre-treating silicon carbide and silicon nitride with hydrochloric acid, and mixing with nano zirconium oxide to obtain a mixture; and modifying the mixture with a silane coupling agent to obtain the modified nano reinforced phase. The high-temperature melting regulator is a mixture of lithium borate, sodium sulfate and lithium fluoride. The preparation method of the ultra-thin flexible glass comprises the following steps: preparing the modified nano reinforced phase, melting and homogenizing the glass, forming the glass substrate, and preparing the ultra-thin flexible glass. The ultra-thin flexible glass prepared by the invention has relatively high fracture toughness and structural rigidity, excellent flexibility and bending fatigue durability, and excellent thermal shock resistance.

The invention relates to the technical field of cables, in particular to a high-flexibility ethylene-propylene insulating rubber material for a charging pile cable and a preparation process. The composite material comprises an ethylene propylene diene monomer, a thermoplastic polyolefin elastomer, an ethylene-butylene copolymer, nanoscale magnesium hydroxide, a silane coupling agent, dicumyl peroxide, a hindered phenol antioxidant and a phosphite antioxidant. The ethylene propylene diene monomer and the ethylene-butylene copolymer form a flexible network skeleton, and the ethylene-butylene copolymer and the thermoplastic polyolefin elastomer are subjected to molecular-level blending, so that the elongation at break and the bending fatigue resistance are improved; silane coupling agent modified nano magnesium hydroxide is chemically bonded with a rubber matrix, so that the flame retardance and thermal aging resistance are enhanced, and the negative influence of filler agglomeration on flexibility is reduced; the compound antioxidant system effectively inhibits thermal oxidation degradation at high temperature, avoids insulation failure, realizes collaborative optimization of high flexibility and high heat resistance, and improves the reliability and applicability of the charging pile cable.

Provided are a rubber composition capable of giving vulcanized molded objects having a satisfactory balance among oil resistance, freeze resistance, and flex fatigue resistance, and a vulcanizate and a vulcanized molded object which have a satisfactory balance among oil resistance, freeze resistance, and flex fatigue resistance.According to the present invention, there is provided a rubber composition including a chloroprene-based rubber and an epichlorohydrin-based rubber, wherein the rubber composition contains 5 to 95 parts by mass of the chloroprene-based rubber and 5 to 95 parts by mass of the epichlorohydrin-based rubber, per 100 parts by mass of rubbers contained in the rubber composition, and the chloroprene-based rubber has a content of an unsaturated nitrile monomer unit of less than 25% by mass.

The invention relates to the technical field of cable preparation, in particular to a robot cable preparation process, which comprises the following steps: twisting a conductor, wrapping a shielding layer and a sheath layer outside a conductive wire core, extruding the shielding layer and the sheath layer, and wrapping a cushion layer, an armor layer and an outer sheath outside the sheath layer. The composite technology brings multiple breakthrough advantages for the cable armor layer through exquisite material design and processing: a firm coating layer formed on the surface of the metal wire by the epoxy coating obviously improves the chemical corrosion resistance of the metal wire, and more importantly, in the subsequent thermocuring process, the coating is used as an active molecular bridge, so that the metal wire can be effectively protected, and the service life of the metal wire is prolonged. The metal wires and the aramid fibers subjected to surface activation form a firm integral network through chemical bonding and mechanical interlocking effects, so that the rigidity and the strength of the metal wires and the toughness and the impact resistance of the aramid fibers are perfectly coordinated, the mechanical enhancement effect of synergistic interaction is realized, and the tensile strength and the repeated bending fatigue resistance are improved.

The present invention relates to the field of braking technology, and in particular to a high- and low-temperature flexural fatigue test method for an air brake hose and its test bench. The method comprises extracting the full stroke of the vehicle's suspension up and down jumps and the full stroke of the steering left and right turns based on the motion characteristics of the vehicle's front and rear axles, fixing one end of the hose to be tested to the fixed end of a flexural circulation device on a test stand and connecting it to a pressure circulation device, and connecting the other end to a movable end and sealing it, and placing the entire test stand in a temperature-controlled test chamber. After the test parameters are set, the test is started, and the flexural circulation device, pressure circulation device, and temperature-controlled test chamber are started synchronously. When the number of working cycles of the flexural circulation device reaches a target preset value, the high- and low-temperature flexural fatigue test of the air brake hose is terminated. The present invention fully considers the bending conditions and high and low-temperature environments of the vehicle's air brake hose, shortens the vehicle verification cycle and verification costs, and is conducive to improving the design quality of the air brake hose.

The invention relates to the technical field of conveyor technology and concerns a textile stranded rope in which individual or all strands of the outer strand layer have a sheath in which the strands can move freely along their lay direction. The object of the present invention is to provide a textile stranded rope that is characterized by improved torsional stiffness with reduced forced twisting, improved flexural fatigue strength, and improved winding properties. This object is achieved by a textile stranded rope comprising a core and at least one strand layer with strands, wherein the core and the strands are made of a textile material and / or a plastic. The at least one strand layer is formed from several textile strands, wherein at least individual strands of an outer strand layer have a tubular sheath.The textile stranded rope can be used, for example, as a load-bearing element in multi-layered wound drum winches.

The invention discloses a composite enhanced high-thermal-conductivity cable, and the cable comprises a conductor layer which is composed of a metal-based composite conductor material; the insulating layer is coated outside the conductor layer and is made of a high-thermal-conductivity insulating composite material; the shielding reinforcing layer is coated outside the insulating layer and is formed by weaving a fiber-conductive composite material; and the sheath layer is coated at the outermost part. A three-dimensional heat dissipation channel from inside to outside is constructed through the graphene composite conductor and the boron nitride composite insulating layer, efficient cooperative heat dissipation is achieved, compared with a traditional cable, the high heat conduction effect is achieved, the current-carrying capacity is remarkably improved, and insulation aging is delayed; meanwhile, the shielding enhancement layer enables the cable to have the characteristics of high tensile strength and bending fatigue resistance while keeping light weight; and the heat insulation buffer layer is matched with the sheath layer, so that the cable is endowed with excellent environmental adaptability, and the technical contradiction that multiple properties such as high conductivity and high heat conductivity, high strength and light weight are difficult to consider at the same time is systematically solved.

Provided are a cellulose fiber-containing resin molded body excellent in flexural fatigue resistance and a cellulose fiber-containing resin composite suitable for obtaining this molded body. 【Solution means】A cellulose fiber-containing resin composite and a cellulose fiber-containing resin molded body, which contain polypropylene resin (PP) and cellulose fiber (CF) and satisfy the following condition 1 or 2. - Condition 1 - The average fiber diameter of CF is 5 to 15 μm, the average fiber length is more than 35 μm and 130 μm or less, and when the ratio of CF in the total amount of PP and CF is Xa mass% and the ratio of soft PP in PP is Ya mass%, inequality A is satisfied. Inequality A: Ya ≥ Xa × 2.5 Xa > 0, Ya > 0 - Condition 2 - The average fiber diameter of CF is 5 to 10 μm, the average fiber length is 35 μm or less, and when the ratio of CF in the total amount of PP and CF is Xb mass% and the ratio of soft PP in PP is Yb mass%, inequality B is satisfied. Inequality B: Yb ≥ Xb × 2.5 - 25 Xb > 0, Yb > 0

The application provides a high-toughness mechanically adaptive bone screw and a preparation method thereof, relates to the technical field of orthopedic implant medical devices, and comprises the following steps: preparing a carbon fiber-polyether ether ketone core mold; preparing a variable-thickness carbon fiber-polyether ether ketone prepreg; conveying the variable-thickness carbon fiber-polyether ether ketone prepreg and an organic film after heat sealing to the surface of the carbon fiber-polyether ether ketone core mold, and layer by layer laying on the carbon fiber-polyether ether ketone core mold to be compacted, molded and prepared into a preform; heating the preform to a specified temperature, extruding and molding through a screw structure mold, and then demolding and heat treating to prepare the bone screw. The application uses the organic film as a toughening layer and designs a coaxial laminated structure, the thickness gradually decreases from the central cylinder to the outer peripheral layer of the screw body, the performance in the aspects of bending fatigue performance and fracture toughness is obviously improved, the relative modulus is significantly lower than that of the bone screw prepared by a traditional scheme, and is closer to the modulus of cortical bone, thereby reflecting the advantages in mechanical adaptation.

This invention relates to the field of polymer materials technology, and discloses a high-elasticity rubber-plastic insulated cable composite material and its preparation method. The high-elasticity rubber-plastic insulation material comprises, by weight, 40-50 parts of EPDM rubber, 20-25 parts of polyolefin elastomer, 30-35 parts of modified calcined kaolin, 3-5 parts of composite antioxidant, 2-3 parts of silane coupling agent, and 1.5-2 parts of vulcanizing agent. During preparation, EPDM rubber and polyolefin elastomer are kneaded for 5-8 minutes, then modified calcined kaolin and silane coupling agent are added and kneaded for another 8-12 minutes, followed by the addition of composite antioxidant and vulcanizing agent and kneading for 3-5 minutes. Finally, the mixture is vulcanized in stages. The first stage vulcanization temperature is 155-160℃, and the second stage vulcanization temperature is 165-170℃. The insulating material prepared by this invention has excellent elasticity, outstanding resistance to flexural fatigue, stable insulation performance, high volume resistivity, excellent aging resistance, and tight interfacial bonding. It is suitable for use in high-voltage cable insulation layers, effectively extending the service life and stability of the cable.

The invention relates to the technical field of high-voltage fast-charging cable manufacturing, in particular to a new energy high-voltage fast-charging flexible cable and a manufacturing system.The manufacturing system comprises a workbench, a wire spool and a limiting structure are sequentially arranged above the workbench, the wire spool rotates through a driving structure, and a mounting frame and a pay-off head are arranged on one side of the workbench; equipments such as an insulating layer co-extruder and a braiding machine are arranged on the other side; the cable is composed of a conductor layer, an insulating layer, a shielding layer and an outer sheath, the conductor layer is formed by stranding silver-plated copper wire harnesses in a layered mode, the insulating layer is made of nanometer modified TPU and ceramic powder composite materials, the shielding layer is of a double-layer structure, and the outer sheath is formed by co-extruding polyether type TPEE and carbon nano tube composite materials. According to the manufacturing system, copper wire twisting can be accurately controlled, layered twisting is achieved, proper pretension is applied, the wire twisting quality and the production efficiency are improved, manual intervention is reduced, and the equipment layout is reasonable; the prepared cable has the advantages of strong fast charging performance, long dynamic bending fatigue life, high safety performance, capability of passing a vertical combustion test, and strong environmental adaptability.

The utility model discloses a cloth clamping packaging paper bag which comprises a bag body, the bag body comprises a bag body and a bottom sealing structure, the bottom sealing structure is located below the bag body, the bag body is cylindrical, the upper end and the lower end of the bag body are open, and the bottom sealing structure is connected with the lower end of the bag body and blocks the lower end opening of the bag body. The bag body sequentially comprises a first paper layer, a first woven cloth layer and a second paper layer from inside to outside. The first woven cloth layer is PP cloth, is a semi-crystalline thermoplastic polymer prepared from propylene monomers through addition polymerization reaction, and has excellent mechanical properties including tensile strength, compression strength and hardness, and outstanding rigidity and bending fatigue resistance. The first woven cloth layer can enhance the pulling resistance of the bag body, so that the bag body is difficult to damage, and material leakage is avoided.

The present application relates to the technical field of cable preparation, and particularly relates to a preparation process of a robot cable, comprising the following steps: conductor stranding, extruding a shielding layer and a sheath layer outside the conductive wire core, and wrapping a cushion layer, an armor layer and an outer sheath outside the sheath layer, the present application combines metal wires, epoxy coating and aramid fibers, and the composite process brings multiple breakthrough advantages to the cable armor layer through ingenious material design and processing: the firm coating layer formed by the epoxy coating on the surface of the metal wire not only significantly improves the chemical corrosion resistance, but more importantly, in the subsequent heat curing process, the coating layer acts as an active molecular bridge, and the aramid fibers after surface activation form a firm overall network through chemical bonding and mechanical interlocking effect, so that the rigidity and strength of the metal wire and the toughness and impact resistance of the aramid fibers are perfectly coordinated, and the mechanical enhancement effect of synergistic effect is realized, and the tensile strength and repeated bending fatigue resistance are improved.

The invention relates to a flexural fatigue resistant suspension bridge sling spherical pad fork ear anchorage structure and a design method, the structure comprises an anchor cup and a fork ear, and is characterized in that the end part of the anchor cup is provided with an external thread, the base of the fork ear is provided with an inner hole, the surface of the inner hole is provided with an internal thread, the end part of the anchor cup is spirally connected with the base of the fork ear, and the fork ear is provided with an external thread. Spherical concave holes are formed in the opposite faces of two lug plates of the fork lug respectively, the spherical concave holes and pin shaft holes of the lug plates are coaxial, the two ends of a pin shaft are sleeved with spherical convex base plates respectively, and the spherical convex base plates make spherical contact with the corresponding spherical concave holes to form a spherical rotation pair. The total length of the fork lug and the anchor cup connecting component is reduced, stress concentration is avoided, the bending moment of the sling acting on the fork lug is further reduced, and the bending fatigue damage risk of the connecting root of the fork lug and the anchorage device is greatly reduced.

The invention discloses a salt-fog-resistant high-flexibility cable for a ship-borne energy storage system, and belongs to the technical field of special cables. The cable comprises a conductor, a conductor insulating layer, a sub-shielding layer, a filler, a total shielding layer, an inner sheath, a braided reinforcing layer and a salt-fog-resistant outer sheath from inside to outside, and has the core innovation points that firstly, the reinforcing layer braided by high-strength synthetic fibers is arranged between the inner sheath and the outer sheath, so that on the premise that the rigidity of the cable is not remarkably increased, the strength of the cable is greatly improved; the tensile property, the torsion resistance and the bending fatigue resistance of the cable are greatly improved; and secondly, the outer sheath is made of a special salt-mist-resistant composite elastomer material, and salt mist erosion is actively defended through a hydrophobic mechanism, a passivation mechanism and a vapor phase corrosion inhibition mechanism. And the conductors and the shielding layer are tinned to form a complete anti-corrosion system from inside to outside. The cable has excellent flexibility, salt spray corrosion resistance, electromagnetic shielding performance and flame retardance, and is especially suitable for frequent movement and vibration scenes of a ship energy storage system in a marine environment.

This invention discloses a flexural fatigue testing device and method for a flexible compensator in a fuel pipeline, comprising: an axial sliding rotary guide mechanism including two rotary support seats, one of which is slidably mounted on a mounting platform, and the other is fixedly mounted on the mounting platform; an axial compensation reciprocating drive platform assembly for driving the rotary support seat slidably mounted on the mounting platform to perform linear motion on the mounting platform; and an angle compensation reciprocating drive platform assembly including a tail flange, a front flange, and two rotary actuators, which are used to drive the tail flange and the front flange to rotate, respectively. This invention can achieve flexural fatigue testing of flexible compensators with simultaneous axial length compensation, unidirectional angle compensation, same-bidirectional angle compensation, or opposite-bidirectional angle compensation compensators; it is simple to operate, stable and reliable, with low processing and maintenance costs, and features high measurement accuracy, good stability, and convenient operation.

The invention discloses a super-wear-resistant, long-service-life, high-flexibility, light-weight and negative-pressure-resistant rubber refueling hose and a preparation method thereof. The invention discloses a super-wear-resistant, long-service-life, high-flexibility, light-weight and negative-pressure-resistant rubber refueling hose. The negative-pressure-resistant rubber refueling hose sequentially comprises an inner rubber layer, a spiral steel wire layer, a middle rubber layer, a fiber woven layer, an outer rubber layer, a transition layer and a wear-resistant protective layer from inside to outside. Or the inner rubber layer, the spiral steel wire layer, the middle rubber layer, the fiber woven layer, the outer rubber layer and the wear-resistant protective layer are sequentially arranged from inside to outside; the spiral steel wire layer is formed by spirally winding a steel wire; the fiber woven layer is formed by weaving one or more of aramid fibers, polyester fibers and vinylon fibers; and the wear-resistant protective layer is made of an ultra-high molecular weight polyethylene film. The negative-pressure-resistant rubber refueling hose meets the negative-pressure-resistant effect, meanwhile, the negative-pressure-resistant rubber refueling hose is lighter in weight, good in flexibility and excellent in wear resistance and bending fatigue performance, and the service life of the hose can be effectively prolonged.

The invention discloses cable bending fatigue life testing equipment, which comprises a mounting rack, and further comprises a test driving mechanism arranged in the mounting rack and used for driving the middle part of a cable to move; the end limiting mechanisms are mounted on the two sides of the test driving mechanism and used for limiting the two ends of the to-be-tested cable; the buffer extrusion assemblies are arranged in the mounting frame and located on the two sides of the test driving mechanism, hydraulic oil is arranged in the buffer extrusion assemblies, and movement of the test driving mechanism is buffered; the elastic pipe is communicated between the end limiting mechanism and the buffer extrusion assembly and is used for conveying hydraulic oil; according to the invention, through the arrangement of a hydraulic linkage structure of the buffer extrusion assembly and the end part limiting mechanism, the self-adaptive adjustment of the clamping force of the cable and the buffer protection of the test driving mechanism are realized.

The invention discloses a polypropylene staple fiber for an automobile wheel casing and a preparation method thereof, and belongs to the technical field of artificial filaments or analogues, the polypropylene staple fiber is prepared from polypropylene resin, an ethylene-propylene-diene terpolymer, maleic anhydride grafted polypropylene, an efficient plasticizer, an antioxidant, a light stabilizer, a nucleating agent and silicone master batch. Compared with the prior art, the high-efficiency plasticizer is introduced, and the elastomer is matched for toughening and interface compatibility improvement, so that the entanglement resistance of a polypropylene molecular chain is reduced, and meanwhile, the stress transfer is optimized, so that the energy dissipation is more uniform when the fiber is stressed or repeatedly bent; the repeated bending fatigue resistance of the fiber is remarkably improved while the fiber is endowed with high elongation at break, and the comprehensive requirements of the automobile wheel cover on the toughness and durability of the material are fully met.

The utility model relates to the technical field of cable structures, and provides a flexible cable, comprising conductors; the insulating layer coats the outer side of the conductor; the buffer layer is arranged on the outer wall of the insulating layer, the buffer layer and the insulating layer are integrally formed, the buffer layer comprises a plurality of buffer parts, the buffer parts are distributed in the circumferential direction of the outer wall of the insulating layer, and any buffer part faces at least part of the opposite side of the outer wall of the insulating layer so as to buffer the bent insulating layer; and the coating layer coats the outer side of the buffer layer and at least abuts against the end part of the buffer part. According to the utility model, through the arrangement of the buffer part, the flexibility and the bending fatigue resistance of the cable are significantly improved while the excellent flexibility of the cable is maintained, the bending life of the cable is greatly prolonged, the safety is higher, and the cable is especially suitable for high-end application scenarios such as robots requiring frequent bending.

This invention discloses a high-hardness, flexurally resistant organic-inorganic composite membrane, its preparation method, and its applications, belonging to the field of organic-inorganic composite material technology. This invention uses calcium phosphate oligomers as an inorganic precursor and bacterial cellulose as an organic precursor. Through organic and inorganic blending and filtration followed by hot pressing, the calcium phosphate oligomers are induced to polymerize in situ within the bacterial cellulose organic network, forming an inorganic network. This allows for the construction of an interpenetrating organic framework inorganic network at the nanoscale, and reversible interfacial bonding sites are formed through the electrostatic interaction between calcium ions and hydroxyl groups. The inorganic network provides rigid support, requiring a larger load to deform under external forces, thereby improving the membrane's stiffness and hardness. During cyclic loading, the interfacial bonding points between the organic and inorganic networks can break and reform, achieving stress dissipation and redistribution, thus improving the membrane's flexural fatigue life.

The present invention provides a rubber composition that can produce vulcanized products and vulcanized molded articles with excellent gas barrier properties, flexural fatigue resistance, and heat resistance. [Solution] According to the present invention, a rubber composition is provided which includes chloroprene rubber and butyl rubber, wherein the rubber composition contains 0.1 to 99 parts by mass of chloroprene rubber per 100 parts by mass of rubber contained in the rubber composition, and the chloroprene rubber contains chloroprene rubber containing unsaturated nitrile monomer units.

The invention relates to the technical field of power-on cables, and provides a cable production line which comprises a cable core preprocessing module, a cable core processing module and a cable forming module, the cable core preprocessing module is used for preliminarily processing wires, the cable core processing module is used for twisting the processed wires and forming a polyurethane coating on the surface of a twisted wire, and the cable forming module is used for forming a cable on the surface of the twisted wire. And the cable forming module is used for adding an insulating layer on the composite wire to form a final product. According to the technical scheme, the problem that only thinner conductor monofilaments can be selected for improving the flexibility of the existing cable is solved, and the uniform polyurethane elastic buffer layer is constructed on the surface of the cable conductor in situ, so that the flexibility of the cable is improved on the premise of ensuring the mechanical strength of the conductor. The bending fatigue resistant life, the interface adhesive force and the long-term use reliability of the cable are remarkably improved, and the core bottleneck of high-end flexible cable manufacturing is solved.

This invention relates to a method for predicting the flexural fatigue life of LSAM-50 considering the temperature-load coupling effect and fatigue limit constraints. Through a systematic innovation across the entire process from material forming, experimental design, data processing to model construction, it is the first to systematically introduce temperature variables and fatigue limit parameters into the flexural fatigue model. This enables an accurate description and quantitative prediction of the fatigue behavior of LSAM-50 under temperature-load coupling, effectively solving three major problems of existing models: failure to consider coupling effects, lack of fatigue limit characterization, and absence of a dedicated model for this ultra-large particle size material. This achievement can provide direct theoretical basis and key design parameters for the fatigue resistance design, life prediction, and integrated optimization of LSAM-50 and its pavement structures, thereby significantly improving the scientific rigor, reliability, and economy of long-life asphalt pavement design.

To provide a polyamide film which is excellent in heat resistance and bending resistance.SOLUTION: There are provided a polyamide-based resin film which contains polyamide (A), and a copolymer (B) including an ethylene unit, a vinyl acetate unit and a vinyl alcohol unit in a molecular chain, wherein a content of (B) to the total of (A) and (B) is 2 to 6 mass%; the polyamide-based resin film, wherein the polyamide (A) is polyamide 6; the polyamide-based resin film, wherein thermal shrinkage percentages of both of an MD and a TD of a film when being heat-treated at 150°C for 15 minutes according to JIS K 7133 are 2.0% or less; and the polyamide-based resin film, wherein an average value of the number of pinholes per 500 cm2 of the film after having been subjected to a 1,000-cycle flexural fatigue test using a Gelbo Flex Tester is 5 or less.SELECTED DRAWING: None

To provide a biaxially stretched polyester resin film that has excellent properties equal to or better than those of biaxially stretched polyester film that does not use recycled raw material, and in particular that has an excellent flexural resistance in low-temperature environments. A biaxially stretched polyester resin film that characteristically satisfies both of the following properties (1) and (2): (1) in differential scanning calorimetry (DSC), after heating from 25° C. to 300° C. at a heating rate of 20° C. / minute and holding for 10 minutes at 300° C., the temperature of crystallization during cooling at a cooling rate of 40° C. / minute is 160° C. to 180° C.; and (2) the number of pinholes after the execution of 200 repetitive cycles of a flexural fatigue test in a −10° C. atmosphere using a Gelbo Flex Tester is not more than 10 / 500 cm2.

This invention discloses a steel bridge deck pavement underlay structure and construction method suitable for heavy traffic, relating to the field of bridge engineering. A stiff fiber reinforcing strip and fiber grid are installed at the bottom of the steel bridge deck pavement structure. Epoxy resin in the epoxy crushed stone layer fills the epoxy resin filling holes, and epoxy resin and crushed stone in the epoxy crushed stone layer fill the mesh of the fiber grid and the mesh of the stiff fiber reinforcing strip. This significantly enhances the flexural tensile strength and flexural fatigue resistance of the pavement structure bottom, and improves the shear strength between the bottom of the steel bridge deck pavement structure and the steel plate, effectively preventing overall shear delamination failure of the steel bridge deck pavement bottom under heavy traffic.

The invention relates to a preparation method of a butterfly-shaped corrugated pipe for low-temperature etching equipment, and belongs to the technical field of control or adjustment in the heat treatment process for changing the physical structure of ferrous metal in iron metallurgy. The method comprises the following steps: firstly, cooling the U-shaped corrugated pipe to below-196 DEG C; pressing waves to form a butterfly-shaped corrugated pipe; then raising the temperature to room temperature; then carrying out electric pulse heat treatment and raising the temperature to 950-1050 DEG C; and finally, third-time purging cooling is carried out. And completing the preparation of the butterfly-shaped corrugated pipe. By adopting the method, austenite is reduced and martensite is increased in the metallographic phase of the corrugated pipe matrix, then the matrix metallographic phase is further converted into the austenite after being heated, and the austenite structure is recrystallized after being cooled, so that a gradient structure from a wave waist to a wave crest and a wave trough is formed, and the bending fatigue life is long.

The invention provides a production process of a flexible electrothermal alloy ribbon. The production process comprises the following steps: S1, screening and proportioning raw materials; s2, smelting and solidifying cast ingots; s3, controlled rolling and controlled cooling hot rolling cogging; s4, precise cold rolling; s5, annealing treatment; s6, surface treatment; and S7, cutting and straightening. The electrothermal alloy ribbon produced by the technical scheme has high flexibility, high bending fatigue strength and excellent thermal cycling stability, is suitable for being applied to heat preservation scenes of batteries of new energy automobiles and the like, and can be attached to the surfaces of the batteries to uniformly provide heat.