1093 results about "Ductility" patented technology

The invention discloses a composite protective structure resistant to blast shock which is mainly a point truss honeycomb integral protective structure formed by a honeycomb tensile layer and a lattice truss-type compression resistance layer through welding spots and connecting keys, and a foam energy absorbing layer is added on the outer layer. According to the composite protective structure, theforce transmission path of a concrete protective structure under the action of blast is innovatively optimized, the resistance level of the protective structure can be greatly improved, and the structure ductility is improved; and the dispersion of concrete fragments in the structure can be restrained, and the phenomenon of blast and explosion-induced collapse of similar traditional concrete protective structures is eliminated.

Provided is a high-strength steel sheet having excellent member strength, ductility, stretch flangeability, bendability of a shear end surface, and low-temperature toughness. A high-strength steel sheet having a prescribed component composition and a steel structure in which the area ratio of martensite is 10%-80%, the area ratio of bainite is 2%-70%, the area ratio of ferrite is 80% or less, and the area ratio of retained austenite is 15% or less at a position at 1 / 4 of the sheet thickness. The ratio of the number of martensite blocks in which metastable carbides are present relative to the number of martensite blocks is 2% or more, and the standard deviation [sigma] n of the nano-hardness relative to the average value [Hn] ave of the nano-hardness is 0.60 x [Hn] ave or less when the nano-hardness at 225 points or more is measured at a position of 1 / 4 of the sheet thickness.

The invention belongs to the technical field of metal material engineering, and relates to a light high-toughness low-cost aluminum alloy and a preparation method thereof.The alloy comprises, by mass, 7.0%-9.2% of Mg, 2.5%-4.0% of Zn, 0.06%-0.20% of Zr, 0.01%-0.03% of Sb, main impurities including Fe smaller than or equal to 0.15%, Si smaller than or equal to 0.12%, other single impurities smaller than or equal to 0.05%, the total impurity smaller than or equal to 0.15% and the balance Al. Compared with 2xxx series and 7xxx series aluminum alloys, the alloy has certain advantages in the aspects of density, specific strength, ductility, corrosion resistance and the like, and has a remarkable cost advantage compared with a low-density aluminum-lithium alloy, so that the core competitiveness of an alloy product is improved, and the alloy product has the potential of becoming a next-generation commercial aluminum alloy.

The invention provides a preparation method of laser cladding heterostructure stainless steel. According to the method, dried stainless steel pre-alloyed powder is subjected to laser melting deposition to form heterostructure stainless steel alloy with cross deposition of coarse grains and fine grains; the grain size of the fine crystal is 3-6 [mu] m, and the structure of the fine crystal layer is an equiaxed structure; the grain size of the coarse crystal is 20-50 [mu] m, and the structure of the coarse crystal layer is a columnar crystal formed along the Z axis. According to the method, the specific coarse grain / fine grain cross deposition heterostructure is presented in the stainless steel by changing the deposition layer process parameters and the scanning path, the material strength is improved while the material ductility is guaranteed, and the alloy has the excellent mechanical property.

The present invention relates to the technical field of steel plate production, and particularly to a thick steel plate for high-strength storage tanks with a low ductile-brittle transition temperature and a preparation method thereof. The chemical components in the steel are as follows: C: 0.22% - 0.26%, Si: 0.13% - 0.144%, Mn: 0.73% - 0.92%, P≤0.015%, S≤0.01%, Cr: 0.03% - 0.049%, V: 0.01% - 0.019%, Nd: 0.00016% - 0.00047%, and the balance is Fe and impurities. Microalloying is used to ensure the excellent internal structure and service performance of the steel plate; the purity of the molten steel is improved by optimizing the smelting process; the internal structure of the steel plate is optimized and the plate shape is improved by adopting a four-stage slab heating process and a three-stage controlled rolling process; the simulated post-weld heat treatment process is used to improve the strength-ductility matching and adjust the microstructure of the material, ensuring the low-temperature service performance of the steel plate in the full thickness direction.

The invention discloses a gradient gradual change type powder material as well as a preparation method and application thereof. The gradient gradual change type powder material comprises a non-metal core, a transition layer, a gradual change layer and a modification layer. The gradient powder material provided by the invention shows excellent strength-ductility synergistic effect, high fracture toughness and enhanced fatigue, wear and corrosion resistance, is good in metal wettability, can effectively reinforce a metal matrix and improve the performance of the metal matrix, can also be well dispersed in resin, and can be applied to the field of metal materials. The gradient powder material disclosed by the invention has a wide application prospect, and can be applied to the fields of heat dissipation of electronic devices, high-speed cutting tools, grinding material and grinding tool materials, high-temperature protection materials and the like.

The invention provides a tension testing device for an automobile fastener wire material, and relates to the field of tension testing devices.The tension testing device comprises an indicating assembly, the indicating assembly is composed of a conversion mechanism and a displacement sensor, the testing assembly can achieve tension testing of the automobile fastener wire material, and the displacement sensor can detect the tension of the automobile fastener wire material while the tension of the material is tested; the indicating assembly can monitor the deformation degree of the material in real time, test data are comprehensive and efficient, the indicating assembly can automatically control starting and stopping of the deformation monitoring function according to the test state, and the problems that an existing tension test device for the automobile fastener wire material is single in test effect, and the tensile strength of the automobile fastener wire material is poor due to ductility of the automobile fastener wire material are solved. The problems that an existing tension testing device cannot record and monitor deformation generated by a material during testing, and testing data are not comprehensive enough are solved.

The invention provides a strengthening and toughening control method for a high-strength titanium alloy welded joint, and relates to the technical field of metal material welding, the strengthening and toughening control method comprises the following steps: S1, during welding, multi-layer and multi-channel gradient heat input is adopted, the heat input quantity of front-channel welding is Q1, the heat input quantity of rear-channel welding is Q2, and Q1 is greater than Q2; s2, after welding, cooling a welding area by stages, adopting inert gas forced convection cooling in a primary cooling stage, adopting water mist pulse cooling when the welding area is cooled to a medium temperature stage, and adopting natural air cooling when the welding area is cooled to a low temperature stage; through the synergistic effect of multi-layer multi-channel gradient heat input and staged cooling, the microstructure and performance of the high-strength titanium alloy welded joint can be effectively regulated and controlled, the structure gradient regulation and control of the titanium alloy welded joint are achieved, the tensile strength, the ductility, the fracture toughness and the creep property of the welded joint are improved, meanwhile, the process can be simplified, and deformation is reduced.

The invention relates to the technical field of simulation, and particularly discloses a finite element simulation method for a steel-concrete mixed structure, and the method comprises the steps: building a finite element model; selecting material parameters and defining a constitutive model; dividing a finite element grid; setting load and boundary conditions; taking the optimized material constitutive parameters as material definition parameters of a formal finite element model; evaluating the critical bearing capacity and ductility performance of the structure; and extracting a displacement field, stress distribution and a load-displacement curve of the structure, and identifying typical mechanical response characteristics of the hybrid structure in elastic, elastoplastic and descending stages. By optimizing constitutive model parameters, high-precision finite element simulation of the whole process from elasticity to damage of the steel-concrete mixed structure is achieved.

The present invention relates to the technical field of concrete. Disclosed is a toughening design method for fiber-reinforced concrete. The method of the present invention changes the passive control characteristics of fibers on a concrete crack propagation process in conventional fiber-reinforced concrete. Starting from the origin of composite material design, firstly, an ultrahigh-ductility composite cementitious matrix is designed; and secondly, an aggregate is incorporated. On the basis of a specific combination of matrix and aggregate parameters, a composite material develops meso-scale multiple cracking and strain-hardening behaviors between aggregate particles during external loading. The fiber-reinforced concrete prepared by this method actively disperses brittle damage and failure within the material, and avoids unstable crack propagation caused by weak interfacial bonding between the aggregate and the matrix. Compared to conventional fiber-reinforced concrete design methods, the present invention more accurately establishes relationships between material compositions, microstructures and macroscopic mechanical response, and more efficiently enhances the toughness of the material.

The invention discloses a method and system for analyzing the rolling resistance of a concrete-filled steel tube combined pier column, and the method comprises the steps: applying an axial compression load to the concrete-filled steel tube combined pier column, and dividing the cross section of the concrete-filled steel tube combined pier column into three layers of regions along a radial material change part; according to corresponding total cross-section average axial strain generated by the steel pipe concrete combined pier column when different axial compression loads are applied, equivalent stress corresponding to each layer of area is calculated, total axial force corresponding to each total cross-section average axial strain is calculated, and a total cross-section average axial strain-total axial force curve is formed; searching a first total cross-section average axial strain corresponding to the maximum value of the total axial force in the total cross-section average axial strain-total axial force curve and a second total cross-section average axial strain corresponding to a first obvious inflection point of the total cross-section average axial strain-total axial force curve, and calculating a ductility coefficient, and judging whether the concrete-filled steel tube composite pier column meets the ductility design requirement or not.

The present invention provides a steel sheet having high strength and high ductility, and a method for manufacturing the same.　The steel sheet has a specific component composition and a structure mainly composed of ferrite. The amount of N present as AlN and the total amount of N satisfy relational expression (1), and the amount of Nb present as Nb precipitates and the total amount of Nb satisfy relational expression (2). The yield strength is 500 MPa or greater, the HR30T hardness is 66 or greater, and the total elongation is 7.0% or more. (1): (Amount of N present as AlN) / (total amount of N) ≤ 0.40 The total amount of N is the amount of all N included in the steel sheet. (2): 0.10 ≤ (amount of Nb present as Nb precipitates) / (total amount of Nb) ≤ 0.80 The total amount of Nb is the amount of all Nb included in the steel sheet.

The invention relates to the field of high-temperature alloy material processing, in particular to a nickel-based high-temperature alloy GH3536 and an SLM preparation and heat treatment process thereof. Through the synergistic effect of ILR and HT, the core pain points of carbide precipitation imbalance and high-temperature instability coarsening in the GH3536 alloy formed through SLM are solved. A high-density subboundary created by the ILR drives short-distance diffusion of carbides at an HT stage to form a uniform spherical nano chain-shaped precipitated phase, so that the strength-plasticity inversion contradiction of a traditional process is broken through, and the strong-plasticity synergistic improvement of the tensile strength and the ductility is realized; the method comprises the steps that in-situ layer-by-layer laser remelting is conducted through the same technological parameters in the SLM process, and then the GH3536 high-temperature alloy is subjected to heat preservation in a vacuum furnace and cooled along with the furnace. The GH3536 high-temperature alloy prepared through the method has excellent performance, the plasticity of the GH3536 high-temperature alloy is equivalent to that of a forged piece, the strength of the GH3536 high-temperature alloy is higher than that of the forged piece, and the GH3536 high-temperature alloy has good industrial application

The invention relates to the field of material science and mechanical engineering, in particular to a high-strength aluminum-magnesium-silicon material bolt for a new energy automobile and a preparation method of the high-strength aluminum-magnesium-silicon material bolt. The bolt is made of an aluminum-magnesium-silicon alloy, and the alloy contains magnesium, silicon, manganese, iron, chromium, titanium, scandium, rare earth elements and the balance of aluminum. By optimizing the proportion of rare earth elements (yttrium, lanthanum and cerium) and scandium, grains are effectively refined, the tensile strength, the yield strength and the ductility are improved, and meanwhile the corrosion resistance and the fatigue resistance are enhanced. The preparation method comprises the steps that vacuum melting is combined with the ultrasonic-assisted technology, alloy elements are evenly distributed, and then the material structure is optimized through solution treatment at the temperature of 540 DEG C for 1.5 h and aging treatment at the temperature of 160 DEG C for 8 h. And the surface of the bolt is subjected to anodic oxidation and coated with a composite coating containing silicon dioxide nanoparticles, so that the wear resistance and the corrosion resistance are improved. Through verification, the bolt has the excellent performance that the tensile strength is larger than or equal to 490 MPa, the yield strength is larger than or equal to 440 MPa, the ductility is larger than or equal to 8.5%, and the salt spray test time is larger than or equal to 1500 hours, and the fastening requirement of the new energy automobile under the complex working condition is met.

The invention relates to the technical field of metal materials, and discloses steel for a battery shell and a preparation method of the steel. The steel for the battery case comprises the following chemical components in percentage by weight: 0.001%-0.004% of C, 0.01%-0.02% of Si, 0.12%-0.22% of Mn, 0.004%-0.01% of P, less than or equal to 0.004% of S, 0.2%-0.4% of Cr, 0.02%-0.05% of Al, 0.015%-0.035% of Ti, 0.001%-0.003% of B, 0.01%-0.03% of Nb and the balance of Fe and inevitable impurities. By accurately controlling the components in the steel, particularly controlling the C content, the niobium content and the chromium content in a proper range, the yield strength, the tensile strength and the ductility of the steel can be improved, and particularly the low-temperature impact toughness of the steel can be improved.

Provided is a steel sheet that may be used for automobile parts and the like, and to a steel sheet having an excellent balance of strength and ductility, an excellent balance of strength and hole expansion ratio, and an excellent yield ratio evaluation index, and a method for manufacturing the same. The steel sheet includes: by wt %, C: 0.1 to 0.25%, Si: 0.01 to 1.5%, Mn: 1.0 to 4.0%, Al: 0.01 to 1.5%, P: 0.15% or less, S: 0.03% or less, N: 0.03% or less, B: 0.0005 to 0.005%, a balance of Fe, and unavoidable impurities; and as microstructures, bainite, tempered martensite, fresh martensite, retained austenite and unavoidable structures.

The invention discloses an Al-Mg-Zn aluminum alloy plate with excellent strong plasticity and light weight characteristics as well as a preparation method and application of the Al-Mg-Zn aluminum alloy plate. The alloy comprises the following components in percentage by mass: 5.0%-5.5% of Mg, 1.5%-2.0% of Zn, 0.4%-0.5% of Mn, 0.1%-0.3% of Cu, 0.15%-0.25% of Sc, 0.1%-0.15% of Zr, 0.05%-0.15% of Ag, less than or equal to 0.1% of impurities and the balance of Al. The density is not more than 2.63 g / cm < 3 >, the tensile strength is not less than 470 MPa, and the ductility is not less than 23%. The preparation method comprises the steps of high-purity raw material smelting and casting, two-stage homogenization, hot rolling, intermediate annealing, cold rolling, solid solution treatment and single-stage aging. Wherein the total pressing amount of hot rolling is 80-85%, the total pressing amount of cold rolling is 20-35%, and the single-stage aging time is 120-140 DEG C * 16-24 h. The microstructure of the alloy is characterized in that the average size of dispersed AlSc particles is smaller than or equal to 100 nm, the area fraction of deformed grains is larger than or equal to 70%, the average size of nanometer beta-AlMg and T-Mg (Al, Zn) composite precipitated phases is smaller than or equal to 20 nm, the number density is larger than or equal to 1 * 10 < m >, the area fraction of micron-order second phases is smaller than or equal to 0.5%, and the alloy is only formed by impurity Fe. According to the method, the traditional two-stage aging process is simplified, low density, high strength and high plasticity are synchronously improved, and the method is suitable for large-scale industrial application.

The invention discloses a heat-treatment-free high-toughness flame-retardant die-casting magnesium alloy and a preparation method thereof, and belongs to the technical field of metal materials. The heat-treatment-free high-toughness flame-retardant die-casting magnesium alloy comprises Mg and the following components in percentage by weight: 5.2%-8.8% of Al, 0.1%-0.5% of Mn, 0.01%-1.0% of Zn, 0.02%-0.1% of Sr, 0.001%-0.5% of Sn, 0.3%-3.9% of La and Ce mixed rare earth, 0.001%-0.5% of Nd, 0.001%-0.35% of Y, 0.001%-0.05% of Ho, 0.01%-0.6% of Ca and inevitable impurities. The die-casting F-state mechanical properties of the heat-treatment-free high-toughness flame-retardant die-casting magnesium alloy at the room temperature are as follows: the tensile strength is 280-300 MPa, the yield strength is 150-180 MPa, and the ductility is 10-16%.

The invention belongs to the technical field of water conservancy projects and pumped storage projects, and discloses a layered injection construction method of a micro-stress ECC parting-free hydraulic anti-seepage panel. Aiming at anti-cracking and anti-seepage challenges of a large-scale seamless hydraulic panel, micro-stress high-ductility injection ECC is injected for multiple times in the thickness direction of the micro-stress ECC parting-free hydraulic panel to form a multi-layer composite integral panel, and transverse and longitudinal joints are not arranged; construction cold joints existing in each spraying layer are covered by the subsequent spraying layers, and the construction cold joints of the adjacent spraying layers do not coincide; and the integral micro-stress ECC joint-free hydraulic panel structure is formed by staggering and overlapping. And by means of the crack control design of staggered joint lap joint and twisting-capturing of the ECC layer face, cooperative improvement of structural bearing and crack resistance and seepage resistance is achieved. Compared with a traditional steel-concrete panel and a traditional asphalt concrete panel, the concrete panel has the advantages of being rigid and flexible, high in construction speed, economical, practical, high in deformation adaptability, resistant to void, resistant to freezing, durable and the like, and the problem that a traditional hydraulic panel gives consideration to crack resistance, seepage resistance and safe service is solved.

The invention discloses a design method for improving the thermal performance of a composite material by regulating and controlling the cluster type and number. The composite material designed by the method consists of an inorganic filler and an organic polymer material matrix, wherein the inorganic filler is a high-thermal-conductivity material and is in a cluster form; and orderly construction of a heat conduction path in the system is realized by regulating and controlling the type and the number of the filler clusters, so that the composite thermal interface material with ultrahigh heat conductivity is obtained under the condition of lower filling volume fraction. The heat-conducting interface material prepared by the method has excellent ductility, can adapt to various thermal interface applications, effectively improves the thermal management efficiency of the device by virtue of the characteristics of ultrahigh heat-conducting property and low filling volume fraction, realizes energy consumption reduction and material saving, further improves the performance release of the device and prolongs the service life of the device.

This invention provides a high-strength, high-ductility austenitic stainless steel and its production method. The composition is: C 0.045%-0.085%, N 0.10%-0.40%, Si 0.90%-1.55%, Cr 16%-20.1%, Ni 7.5%-12.5%, Mn 1.5%-3.5%, Mo 1.5%-3.0%, Nb 0.08%-0.22%, Ti 0.015-0.065%, O≤0.005%, P≤0.003%, S≤0.003%, with the remainder being Fe and unavoidable impurities. Compared with existing technologies, this invention obtains a reasonable grain size and second-phase particles through nitrogen, titanium, and niobium alloying, combined with low-temperature rolling and appropriate annealing and aging heat treatment, thus developing an austenitic stainless steel with excellent mechanical properties. It achieves excellent ductility at a high strength level, with a strength-ductility product as high as 60 GPa·s.

The invention relates to the technical field of maritime work steel production, in particular to an ultrahigh-toughness wear-resistant maritime work steel plate based on gradient structure design and a manufacturing method thereof, and the steel plate comprises the following chemical components in percentage by mass: 0.03%-0.09% of C, 0.85%-1.45% of Si, 1.4%-2.0% of Mn, 0.5%-0.9% of Cr, 5.0%-8.5% of Ni, 0.2%-0.6% of Mo, 0.6%-1.2% of Cu, 0.012%-0.025% of Ti, 0.02%-0.06% of Nb, 0.03%-0.07% of Al, 0.010%-0.018% of Ce, 0.003%-0.006% of B, less than or equal to 0.005% of P, less than or equal to 0.002% of S and the balance of Fe and inevitable impurities. The integrated performance upgrading that one side of the steel plate is wear-resistant and the other side is tough is realized. And the wear resistance, the ductility and the low-temperature toughness of the ultrahigh-strength steel plate are greatly improved.

The invention relates to large-thickness high-homogeneity polar region ship low-temperature steel and a preparation method thereof. The steel plate comprises the following chemical components in percentage by weight: 0.06%-0.12% of C, 0.15%-0.35% of Si, 1.10%-1.40% of Mn, less than or equal to 0.008% of P, less than or equal to 0.008% of S, 0.020%-0.050% of Nb, 0.020%-0.040% of Al, 0.010%-0.020% of Ti, 0.04%-0.08% of residual element Mo and the balance of Fe and inevitable impurity elements. The carbon equivalent CEV is less than or equal to 0.38%, and the cold crack sensitivity index Pcm is less than or equal to 0.20%. The manufacturing process of the steel plate comprises the steps of KR, BOF smelting, LF, RH, slab continuous casting, slab slow cooling, heating, rolling, steel plate pile slow cooling and heat treatment, the matrix structure of the obtained steel plate is a uniform and fine ferrite and tempered pearlite mixed structure, and the grain size ranges from 8 micrometers to 15 micrometers. The yield strength of the transverse tensile property at the 1 / 4 position of the steel plate ranges from 376 MPa to 392 MPa, the tensile strength ranges from 528 MPa to 553 MPa, the ductility is larger than or equal to 27.0%, the yield strength of the transverse tensile property at the 1 / 2 position ranges from 359 MPa to 375 MPa, the tensile strength ranges from 524 MPa to 537 MPa, the ductility is larger than or equal to 26.5%, and the steel plate is excellent in performance, excellent in whole plate uniformity, good in plate shape and easy to weld.

The invention relates to ultra-low carbon steel, a preparation method thereof and a steel product. The preparation method of the ultra-low carbon steel comprises the following steps: providing a casting blank; sequentially heating and hot-rolling the casting blank to obtain hot rolled steel; the hot rolling comprises rough rolling and finish rolling which are sequentially carried out, the initial rolling temperature of the rough rolling is 990-1040 DEG C, and the outlet temperature of the rough rolling is 900-940 DEG C; the initial rolling temperature of finish rolling ranges from 840 DEG C to 890 DEG C, and the final rolling temperature of finish rolling ranges from 750 DEG C to 830 DEG C; and the hot rolled steel is sequentially subjected to acid pickling, cold rolling and annealing. According to the preparation method, ferrite area low-temperature rolling is adopted, the heating energy consumption is remarkably reduced, the production efficiency is improved, the problem of scale thickening caused by traditional high-temperature rolling is avoided, the surface quality of the strip steel is more uniform, and the pickling cost is greatly reduced. Meanwhile, the ductility, the strain hardening index (n value) and the plastic strain ratio (r value) of the obtained finished product are remarkably improved, and the forming performance is excellent.

The invention belongs to the technical field of metal materials, and relates to a CoNiVAlX (x is greater than or equal to 0 and less than or equal to 0.5) multi-principal-element heterostructure entropy alloy system and a preparation method thereof. The chemical composition (atomic percent) of the alloy contains Co, Ni, V, Al and a trace regulator, flexible matching of strength and toughness is realized in a wide temperature range of-263 DEG C to 800 DEG C by regulating the Al content and a thermal mechanical treatment process, and various mechanical states such as'high ductility-medium strength 'and'high strength-medium ductility' can be obtained; the preparation process is based on a mature metallurgical technology and does not depend on special equipment, and large-size stable preparation can be achieved. Tests prove that the alloy system is wide in toughness and adjustable, the toughness balance in a wide temperature range is realized, the application requirements in an extreme environment are met, and the alloy system has a good industrial popularization prospect.

A process for forming extruded products using a device having a scroll face configured to apply a rotational shearing force and an axial extrusion force to the same preselected location on material wherein a combination of the rotational shearing force and the axial extrusion force upon the same location cause a portion of the material to plasticize, flow and recombine in desired configurations. This process provides for a significant number of advantages and industrial applications, including but not limited to extruding tubes used for vehicle components with 50 to 100 percent greater ductility and energy absorption over conventional extrusion technologies, while dramatically reducing manufacturing costs.

A process for forming extruded products using a device having a scroll face configured to apply a rotational shearing force and an axial extrusion force to the same preselected location on material wherein a combination of the rotational shearing force and the axial extrusion force upon the same location cause a portion of the material to plasticize, flow and recombine in desired configurations. This process provides for a significant number of advantages and industrial applications, including but not limited to extruding tubes used for vehicle components with 50 to 100 percent greater ductility and energy absorption over conventional extrusion technologies, while dramatically reducing manufacturing costs.

The invention discloses a method and system for determining the optimal stress orientation of a concrete special-shaped sheet column, and relates to the technical field of constructional engineering. According to the method, a correlation model of special-shaped contour parameters and load conditions is constructed, a mechanical property key direction set is extracted, the screening range is narrowed, the optimal orientation determination efficiency is greatly improved, the design period is shortened, and the optimal orientation determination efficiency is improved based on multi-dimensional screening of all-circumferential inertia moment distribution, a rigidity curve and a bending moment contribution ratio. Core indexes such as section ultimate bearing capacity and ductility are comprehensively evaluated by combining stress simulation of a concrete nonlinear constitutive relation; through overall structure collaborative checking calculation and node stress analysis, it is ensured that the orientation meets the mechanical requirements of components and adapts to lateral force resistance and stress continuity of the overall structure, in combination with building construction requirements and node compressive strength redundancy optimization, the scheme of optimal mechanics but construction conflicts is eliminated, safety redundancy is reserved, the structure anti-disaster stability is guaranteed, and the construction safety is improved. And meanwhile, the method adapts to complex working conditions and specification requirements and ensures that the scheme can be directly applied.

According to the 3D printing concrete truss girder structure based on three-dimensional steel bar reinforcement and the construction method, through space welding connection of the three-dimensional conical steel bars and the top plane steel bars, the interlayer bonding performance and the overall stress performance of a 3D printing concrete truss girder are remarkably improved. The three-dimensional conical steel bars comprise plane steel bars matched with the truss girder in length and width and a plurality of three-dimensional conical steel bar units, the three-dimensional conical steel bar units are arranged in the mode that the height of a three-dimensional space component formed by bending metal steel bars crosses over at least one or more concrete printing layers, and the plane steel bars are buried in the lower layer concrete. And the upper ends of the three-dimensional conical steel bar units are fixedly connected with the top vertical rod section steel bars of the top plane steel bars on the upper layer or the higher layer or the vertical bars of the next plane steel bars, so that an integral space steel bar framework is formed. The steel plate has higher shear bearing capacity, better ductility and a better failure mode, and is suitable for load-bearing components in various building and bridge engineering.

The invention discloses a multi-cavity aluminum alloy battery pack shell extrusion-bending process optimization method, and relates to the technical field of aluminum alloy machining. According to the method, 6000 series aluminum alloy serves as a base material, and the problems of cracking, resilience, section deformation and uneven performance of a profile in the traditional process are solved through the six-step core process of compound trace element regulation and control, gradient heating ingot casting, PID temperature control extrusion, segmented quenching temperature control, multi-roller cooperative bending and online structure monitoring. The strength and plasticity of the alloy are improved through Mn / Zr or Cu / Ag composite microalloying, extrusion-bending continuous forming and real-time grain boundary migration and dislocation density monitoring are combined, and the multi-cavity structure size precision (the broad side error is + / -1.87 mm, and the narrow side error is + / -0.40 mm) and the mechanical property (the tensile strength is larger than or equal to 200 MPa, and the percentage elongation after fracture is larger than or equal to 8%) both reach the standard. The process shortens the processing period by more than 30%, improves the material utilization rate to 92%, is suitable for large-scale mass production of new energy automobile battery pack shells, and provides key technical support for automobile lightweight.