32 results about "Carbon corrosion" patented technology

The present application relates to the technical field of metallurgy, and particularly relates to a production method of a large-wall-thickness pipeline steel with improved carbon dioxide corrosion resistance and strength and toughness, and specific measures include: (1) controlling the bottom blowing mode and end point requirement in the converter process; (2) controlling the tapping time and replacing the tapping hole opportunity in the tapping process; (3) feeding the CAS aluminum wire and controlling the CAS argon blowing time; (4) controlling the top slag addition amount, heating time and outgoing mode in the LF refining process; (5) controlling the wire feeding parameters, soft blowing time and outgoing requirement of RH in the RH refining process; (6) controlling the precision requirement, casting speed fluctuation and crystallizer liquid level fluctuation of the continuous casting equipment in the continuous casting process to obtain the casting blank. Through controlling the parameters of each process in the smelting and rolling process, the present application realizes the whole-process steel cleanliness control and ladle grain refinement, and further improves the strength, low-temperature toughness, HIC resistance and carbon dioxide corrosion resistance of the large-wall-thickness pipeline steel.

The invention relates to the field of inorganic functional materials, and particularly discloses a corrosion-resistant layered Pt-C catalyst and a preparation method and application thereof. The nitrogen-doped carbon carrier, the spinel oxide and the Pt nanoparticles are arranged to form a novel corrosion-resistant catalyst, and through the synergistic effect of the spinel oxide AB2O4 and the nitrogen-doped carbon carrier N-Carbon, the electron cloud density on the surface of the carbon carrier is effectively reduced, the carbon corrosion problem of traditional Pt / C under high potential is inhibited, and the carrier stability is remarkably improved; spinel oxide is used as an anchoring point of platinum nanoparticles, the migration energy barrier of the platinum nanoparticles is improved, the platinum utilization rate is improved through an in-situ precipitation process, the comprehensive cost is reduced compared with commercial Pt / C, and due to the fact that the production process is simple and the production period is short, the production cost is reduced. The catalyst shows excellent oxygen reduction reaction catalytic activity and stability in zinc-air cells and fuel cells, the preparation method is simple, special equipment is not needed, and the catalyst has good industrial amplification potential.

The present invention provides a membrane electrode assembly for preventing reverse voltage of a fuel cell, comprising an electrolyte membrane between a positive electrode and a negative electrode, in which the positive electrode and the negative electrode each comprise a supported catalyst in which a metal catalyst is supported on a support, wherein the ratio MCL / R between the metal catalyst loading amount MCL in the negative electrode and the loaded metal catalyst ratio R is 0.125 to 0.3. This membrane electrode assembly can prevent an overflow phenomenon that may occur in cold start driving or fast acceleration driving by appropriately controlling physical property factors associated with a fuel cell negative electrode. Thus, this membrane electrode assembly can suppress carbon corrosion at the negative electrode and improve durability.

The invention discloses a tantalum oxide / carbon-loaded high-stability platinum-based fuel cell cathode catalyst and a preparation method thereof.According to the metal oxide composite carrier-loaded platinum catalyst provided by the invention, excessive growth of a metal oxide is limited by utilizing the confinement effect of mesoporous carbon, amorphous TaOx in a low oxidation state is formed at a high temperature, and the tantalum oxide / carbon-loaded high-stability platinum-based fuel cell cathode catalyst is prepared. TaOx is uniformly dispersed in the carbon substrate in the form of small particles. Pt is selectively anchored on TaOx, the formed platinum particles are small in size, and the high precious metal utilization rate is guaranteed. The problem of catalyst performance loss caused by carbon corrosion is effectively solved by utilizing the strong corrosion resistance of the metal oxide. The preparation method is simple, low in cost and good in reproducibility, and compared with an existing commercial catalyst, the prepared tantalum oxide loaded high-stability platinum-based fuel cell cathode catalyst is higher in catalytic activity and better in stability.

The invention provides a fuel cell bipolar plate and a preparation method thereof. The fuel cell bipolar plate comprises a metal bipolar plate, a self-repairing transition layer covering the surface of the metal bipolar plate and a carbon coating covering the surface of the self-repairing transition layer, and the self-repairing transition layer contains a high-molecular polymer. The main component of the self-repairing transition layer arranged on the surface of the metal bipolar plate is a high-molecular polymer, a network structure formed by the self-repairing transition layer not only can enable a carbon coating to be firmly combined with the metal bipolar plate, but also has relatively high binding force with an oxide film layer on the surface of the metal bipolar plate, and the polymer can continuously grow in an operating environment of a fuel cell, so that the service life of the fuel cell is prolonged. And after the local carbon coating is damaged and corroded, the coating can be self-repaired due to the binding characteristic of the polymer, so that the performance loss of the galvanic pile caused by local carbon corrosion is prevented.

This invention discloses a Pt / O-NCP catalyst and its preparation method. It utilizes self-developed nanoporous carbon (NCP) as a support, which is modified to change the internal pores from a hydrophobic to a hydrophilic state. A special preparation method is then used to obtain the noble metal catalyst Pt / O-NCP. During catalyst loading, most Pt nanoparticles are located within the mesopores of the support, maximizing the direct contact between the polymer and Pt (sulfonic acid poisoning). This solves the problems in existing catalysts where Pt nanoparticles are prone to dissolution and carbon corrosion under voltage fluctuations, leading to Pt growth and aggregation, thus avoiding the reduction in catalytic performance caused by a decrease in the active surface area of ​​the catalyst. Furthermore, this catalyst can also address the significant decrease in overpotential of ordinary carbon support materials under low humidity, resolving the typical performance degradation of PEMFCs under low humidity conditions.

According to the X65 pipeline steel for conveying supercritical carbon dioxide and the manufacturing method of the X65 pipeline steel, the production process is simple, existing metallurgical equipment, steel rolling equipment and cooling equipment do not need to be updated, additional equipment does not need to be added, and industrial production can be directly conducted. The low-temperature crack initiation and crack arrest toughness of the steel plate can be greatly improved, the carbon dioxide corrosion resistance can be greatly improved, and large economic benefits are produced.

The application relates to the technical field of steel production, in particular to a carbon dioxide corrosion-resistant steel and a preparation method thereof.The chemical components of the steel include C, Cr, Mn, Nb, Si, P, S and Fe; wherein the content of C is 0.05-0.15 wt%, the content of Cr is 1-3 wt%, the content of Mn is 1-1.5 wt%, the content of Nb is 0.025-0.055 wt%, the content of Si is 0.2-0.3 wt%, the content of P is <=0.008 wt%, and the content of S is <=0.002 wt%. The application solves the technical problem that the existing steel has poor carbon dioxide corrosion resistance.

The utility model provides an anode gas diffusion layer structure and an anti-antipole membrane electrode. An anode micropore layer is arranged on one side of an anode substrate layer, and an anode anti-antipole layer is arranged on the other side of the anode substrate layer. The antipole resistance is more directly contacted with the humidified gas, so that the antipole resistance of the membrane electrode is improved, and the occurrence time of carbon corrosion is delayed; the anti-reverse pole coating is not in direct contact with the catalyst, so that the shielding effect on the performance of the fuel cell is avoided, and the performance of the cell is improved; the anti-antipole coating is independently prepared, the plane gradient design of the antipole performance of the GDL can be more conveniently achieved, more anti-antipole catalysts are sprayed to the anode outlet area and the area close to the edge of the flow field, and the cost is effectively saved.

The present invention provides a gas diffusion electrode which is capable of restraining the progression of carbon corrosion at an anode gas diffusion electrode of a fuel cell even in a reverse potential state that is caused by deficiency of a fuel supplied to the anode gas diffusion electrode, and which is therefore free from a decrease in the power generation performance of the cell. This gas diffusion electrode includes a conductive porous base material that contains carbon fibers as a constituent material, and a microporous layer that is in contact with one surface of the conductive porous base material; and this gas diffusion electrode is characterized in that the microporous layer contains, as constituent materials, carbon fine particles and a fluororesin that has a fluoroalkyl chain, and if A (m2 / g) is the specific surface area of the carbon fine particles, B (g / cm3) is the content of the carbon fine particles per unit volume in the microporous layer, and C (g / cm3) is the content of the fluororesin that has a fluoroalkyl chain per unit volume in the microporous layer, the value obtained by the formula X described below is 10 to 50. (Formula X): A−30×(C / B).

This utility model discloses a high-sealing, carbon dioxide corrosion-resistant, heat-insulating oil casing, specifically relating to the field of heat-insulating oil casing technology. It includes a pipe body and a coupling. The coupling is threadedly connected to the outer end of the pipe body. A fixing plate is fixedly installed on one side of the outer surface of the pipe body. The fixing plate has multiple fixing holes inside, and two springs are fixedly installed on the inner top surface of each fixing hole. In practical operation, the end of the pipe body is inserted into the coupling and rotated to achieve a threaded connection. Under the elastic action of the springs, a limiting hook extends to the side outside the fixing hole and inserts into the limiting hole of the connecting plate, thus engaging with the threaded connection to assemble and connect the pipe body and the coupling. The elastic force of the springs provides continuous clamping force, effectively offsetting the preload attenuation caused by vibration. The insertion and engagement of the limiting hook and the limiting hole further restricts axial displacement, effectively preventing loosening between the pipe body and the coupling from affecting the transport of heavy oil.

The invention relates to manufacturing of a pipeline steel hot-rolled coiled plate for a longitudinal welded pipe, in particular to 450MPa-grade carbon dioxide corrosion resistant steel and a manufacturing method of the 450MPa-grade carbon dioxide corrosion resistant steel. The steel comprises the following chemical components: C, Si, Mn, less than or equal to 0.020% of P, less than or equal to 0.002% of S, less than or equal to 0.008% of Cr, Cu, V, Ti, Al, less than or equal to 0.008% of N and the balance of Fe and inevitable elements. According to the steel plate, the transverse yield strength is 470 MPa or above, the tensile strength is 580 MPa or above, the yield ratio is smaller than or equal to 0.87, the elongation A50 mm is larger than or equal to 39%, the impact energy at the temperature of-40 DEG C is 280 J or above, the drop weight at the temperature of-20 DEG C is larger than or equal to 95%, and according to the ASTM-G111 corrosion standard, the average corrosion rate in the carbon dioxide environment is smaller than 0.10 mm / a; the longitudinal yield strength is 460 MPa or above, the tensile strength is 570 MPa or above, the yield ratio is smaller than or equal to 0.86, and the elongation A50 mm is larger than or equal to 38%.

The present invention provides a film electrode assembly with high carbon corrosion resistance. [Solution] The membrane electrode assembly comprises an anode-side electrode catalyst layer, a solid polymer electrolyte membrane, and a cathode-side electrode catalyst layer in this order. The anode-side electrode catalyst layer and the cathode-side electrode catalyst layer each contain catalyst particles, a carbon support carrying the catalyst particles, and a polymer electrolyte, and the volume density of the anode-side electrode catalyst layer is smaller than the volume density of the cathode-side electrode catalyst layer.

The invention relates to the technical field of fuel cells, in particular to a hydrogen fuel cell protection system and a control method, and the system comprises a relay array which comprises a plurality of relays, and two endpoints of each relay are connected in parallel to the positive electrode and the negative electrode of a corresponding single cell; the shut-off valve array comprises a plurality of shut-off valves, each shut-off valve is arranged on an anode intake manifold of the corresponding single cell and controls the anode intake manifold to be opened and closed, the anode intake manifolds and a hydrogen intake manifold of the hydrogen fuel cell are connected with a controller, and the controller is connected with the relay array and the shut-off valve array. And the fault level of each single battery is determined according to the operation parameters of each single battery, a control instruction is generated according to the fault level, and at least one of the relay array and the stop valve array is controlled by using the control instruction. Therefore, the problems of irreversible carbon corrosion reaction and the like of the anode of the faulted battery caused by reverse current of the battery after the fuel battery single battery breaks down and hydrogen is cut off are solved.

The low-carbon corrosion-resistant high-strength stainless steel pipe for the heat exchanger comprises a plurality of straight pipes, bent pipes, anti-breaking frames, connecting columns and expansion frames, the number of the straight pipes is multiple, and the adjacent straight pipes are fixed together through the bent pipes; anti-breaking frames are fixed to the outer side faces of the straight pipes, and connecting columns are fixed between the anti-breaking frames fixed to the outer side faces of the adjacent straight pipes. And a plurality of extension frames are fixed on the outer side surface of the straight pipe. Due to the arrangement of the straight pipes, the anti-breaking frames and the expansion frames, when the heat exchanger is used, the flow speed of fluid in the pipe body can be prevented from being too high, the distance between the adjacent straight pipes can be prevented from being changed, meanwhile, the heat exchange area is increased, and therefore the heat exchange efficiency of the heat exchanger is improved.

The present application relates to a kind of manufacture of pipeline steel hot-rolled coil for straight seam welded pipe, especially 450MPa grade carbon dioxide corrosion resistant steel and its manufacturing method.The chemical composition in steel contains:C, Si, Mn, P≤0.020%, S≤0.002%, Cr, Cu, V, Ti, Al, N≤0.008%, the rest is Fe and inevitable element.The transverse yield strength of steel plate is 470MPa or more, tensile strength is 580MPa or more, yield ratio≤0.87, elongation A 50mm ≥39%, impact energy at-40 ℃ is 280J or more, drop hammer at-20 ℃≥95%, according to ASTM-G111 corrosion standard, average corrosion rate in carbon dioxide environment is less than 0.10mm / a;Longitudinal yield strength is 460MPa or more, tensile strength is 570MPa or more, yield ratio≤0.86, elongation A 50mm ≥38%.

The invention discloses a platinum cluster enhanced electro-catalytic oxygen reduction activity catalyst, catalyst slurry, a working electrode and a preparation method, the catalyst comprises a graphite flake loaded with a low loading amount of Pt nanocluster, namely Pt-D / O-C; wherein the low loading capacity is less than 1.5 wt%. According to the present invention, the cheap, easily available and efficient carbon material is adopted as the electrode, such that the operation is simple, the carbon electrode has good stability and can be recycled for multiple times, the ORR activity can be enhanced and the cost can be reduced in the aspect of the effect, the problems of carbon corrosion, Pt aggregation and the like during the reaction process can be avoided, and the great application potential in the industry can be provided. Meanwhile, the catalyst slurry, the working electrode and the preparation method provided by the invention also have the same effect.

The application discloses a high-strength oil casing pipe with carbon dioxide corrosion resistance, which contains Fe and inevitable impurities, and additionally contains the following chemical elements: C: 0.10-0.20%, Si: 0.10-0.80%, Mn: 0.10-1.50%, Cr: 3-5%, Mo: 0.10-0.70%, Al: 0.01-0.10%, V: 0.10-0.20%, Ni: 0.1-1.0%, Ce: 0.002-0.01%, and La: 0.002-0.01%. Correspondingly, the application also discloses a manufacturing method of the high-strength oil casing pipe with carbon dioxide corrosion resistance. The oil casing pipe with super-high strength and excellent carbon dioxide corrosion resistance can be obtained through reasonable chemical element component design.

The invention discloses a membrane electrode for a proton exchange membrane fuel cell. The membrane electrode comprises multiple layers of proton exchange membranes as well as catalyst layers and diffusion layers which are symmetrically and sequentially arranged on two sides of the multiple layers of proton exchange membranes from inside to outside, the multi-layer proton exchange membrane comprises a middle membrane layer formed by compounding low-EW perfluorinated sulfonic acid resin and PVDF (Polyvinylidene Fluoride), the low-EW perfluorinated sulfonic acid resin film layer, the high-EW perfluorinated sulfonic acid resin film layer, the composite inner layer and the composite outer layer are symmetrically arranged on the two sides of the middle film layer from inside to outside, wherein the composite inner layer is formed by mixing low-EW perfluorinated sulfonic acid resin, rare metal oxide and dopants of the rare metal oxide, and the composite outer layer is formed by mixing low-EW perfluorinated sulfonic acid resin and nano platinum metal. The prepared membrane electrode for the proton exchange membrane fuel cell has the characteristics of high mechanical strength, stable chemical property and the like, and meanwhile, the problems of relatively high interface resistance between a catalyst layer and a proton exchange membrane of the proton exchange membrane fuel cell and carbon corrosion after anode reversal are effectively solved.

The utility model provides a high-efficiency grinding machine for a low-carbon corrosion-resistant stainless steel pipe, which comprises a foundation plate, a support, a top plate, a screw driving structure, a driving structure, a sand blasting grinding structure, a sand discharging structure, a rotating motor and a steel pipe, the screw driving structure is mounted between the foundation plate and the top plate; the driving structure is fixedly mounted at the top of the top plate and is in transmission connection with the screw driving structure, the sand blasting and grinding structure is mounted on the screw driving structure, and the sand discharging structure is fixedly mounted on one side of the sand blasting and grinding structure; the rotating motor is fixedly installed on the surface of the foundation plate, and the steel pipe is clamped and fixed to the top of the rotating motor. Due to the arrangement of the sand blasting and polishing structure and the sand discharging structure, the surface treatment effect is uniform, waste sand and waste material management is perfect, the automation degree is high, and the labor intensity is low.

The present invention discloses a battery performance prediction method based on carbon corrosion of the catalytic layer. In the battery performance prediction method based on carbon corrosion of the catalytic layer, a dual-site carbon corrosion kinetic reaction equation group is adopted, and the carbon-based mass loss under different operating voltage cycle conditions is calculated based on the Newton method. The carbon mass is converted into the evolution of the carbon particle diameter in the agglomerate model according to the conservation of carbon mass within each time step, and then the change of the microstructure of the catalytic layer is deduced, and the catalytic layer thickness, ionomer volume fraction, catalyst volume fraction and porosity are updated. The average radius of the Pt particles is predicted using a Pt aging radius model. According to the structural parameters of the catalytic layer after aging, the gas diffusion coefficient, proton conductivity and local mass transfer resistance and other parameters in the battery model are updated. By iteratively solving the battery model, the battery performance after carbon corrosion of the catalytic layer is predicted.

The present invention provides a carbon-free electrocatalyst for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs). Described herein is a Pt decorated carbon-free catalyst with solid-state proton conducting zirconium phosphate (ZrP) as support material for PEMFC. The invention further describes the process for obtaining said Pt decorated conducting zirconium phosphate (ZrP) as support material as proton conductor. Also, the present invention relates to an efficient proton conductor which optimizes utilization of Pt- catalyst thereby improving the performance of the PEMFC. The carbon-free system alleviates the problem of carbon-corrosion leading to detachment of Pt-nanoparticles.

The invention belongs to the technical field of nano materials and electro-catalysis, and discloses a sandwich-structure nano-particle catalyst and a preparation method thereof.The sandwich-structure nano-particle catalyst comprises a molybdenum carbide nano-particle inner core and a shell layer covering the molybdenum carbide nano-particle inner core, the shell layer comprises platinum or an alloy consisting of platinum and at least one element selected from transition metal, rare earth metal or metalloid; molybdenum carbide can be used as an inner core, platinum or platinum-based alloy can be used as a shell layer, platinum dissolution and carbon corrosion can be synchronously inhibited, and the service life of the fuel cell catalyst is remarkably prolonged.

The invention provides a dynamic and static umbilical cable, and relates to the technical field of umbilical cables. Comprising at least one steel pipe, the steel pipe comprises a dynamic section and a static section, the inner diameter of the dynamic section is the same as that of the static section, the wall thickness of the dynamic section is larger than that of the static section, and the dynamic section and the static section are connected in a welded mode; at least one light unit; at least one electrical unit; the coating structure coats the peripheries of the steel pipe, the optical unit and the electric unit; the outer diameter of the first end of the unequal-diameter joint pipe is larger than that of the second end of the unequal-diameter joint pipe, the first end of the unequal-diameter joint pipe is connected with the dynamic section in a welded mode, and the second end of the unequal-diameter joint pipe is connected with the static section in a welded mode. According to the dynamic and static umbilical cable, the fatigue life of the dynamic and static umbilical cable is prolonged by increasing the wall thickness of the dynamic section steel pipe on the premise that the overall size of the dynamic and static umbilical cable is kept consistent. The production difficulty and cost are reduced, and the problems of overlarge rigidity and carbon corrosion of the connector box are effectively avoided.

The invention discloses a method for reducing converter tapping oxygen of ultra-low carbon anti-corrosion pipeline steel, which relates to the technical field of steel production and comprises the following steps: controlling the unit consumption of molten iron to be greater than 910kg / t; slagging by adopting a single-slag method calcium slagging path; a'high-low-high-low 'bottom blowing mode is adopted; lime accounting for 90% of the total amount of the lime and all the magnesium balls are added within two minutes of blowing in the blowing process, and the remaining lime is added after process measurement is finished. According to the method, the converter charging amount system and the converter operation are optimized, the converter tapping oxygen qualification rate of the ultra-low carbon corrosion-resistant carbon pipeline steel can reach 95% or above, the Fe content in converter slag is effectively reduced, the furnace production is improved, and the purity of the molten ultra-low carbon pipeline steel is improved. Meanwhile, the slag splashing effect is improved, the adhesion rate of the slag is greatly increased, the erosion degree of a furnace lining is reduced, the dosage of a slag regulator is reduced, the furnace protection quality is improved, the smelting period is shortened, the production efficiency is improved, and the productivity of the converter is released.

The application provides a control method for eliminating high potential of fuel cell start-stop, comprising: obtaining the stack operation state of a fuel cell system, obtaining the cathode potential data of the stack under the start condition and the shutdown condition based on the operation state; judging whether the fuel cell system is in a high potential state according to the cathode potential data, and triggering a recovery module to perform a high potential elimination operation if the fuel cell system is in the high potential state. The stack is monitored in real time, and the working condition of the fuel cell is dynamically adjusted, so that the purpose of reducing the cathode high potential condition is achieved, and the fuel cell stack can work efficiently for a long time. The occurrence of the cathode high potential is reduced by controlling the adjustable load element, and the carbon corrosion problem is further inhibited; the occurrence of the high potential is reduced, so that the attenuation of the fuel cell performance caused by the carbon corrosion under the high potential condition is reduced, and the service life of the fuel cell is prolonged.

The invention discloses a PEMFC frequency modulation control method based on adaptive power tracking control, and provides an active power-frequency droop control method for droop coefficient self-adjustment by considering the relationship between frequency and power and considering the characteristics of a PEMFC. Secondly, a self-adaptive power tracking control algorithm is provided based on the basic principle of a perturbation observation method, so that the PEMFC has the capability of dynamically adjusting the output power so as to support the system frequency; and finally, considering the maximum power point characteristic of the PEMFC, limiting the operating point of the PEMFC, and avoiding the situation that the service life of the PEMFC is shortened due to the fact that a large amount of energy is wasted and electrode carbon corrosion is caused by insufficient reactant supply caused by high current density when the PEMFC operates in a concentration polarization region. When the system is disturbed, the reference power required to be output by the PEMFC is calculated according to droop control, and then the actual output power of the PEMFC is dynamically adjusted according to the adjustment requirement by using a self-adaptive power tracking control algorithm, so that power compensation is performed on the system, and the frequency stability of the system is improved.

The present application relates to a kind of straight seam welded pipe for pipeline steel hot-rolled plate manufacturing, especially to a kind of 450MPa grade low yield ratio resistance carbon dioxide corrosion steel and its manufacturing method.The chemical composition in steel contains:C, Si, Mn, P≤0.020%, S≤0.002%, Cr, Cu, Nb, Ti, Al, Zr, N≤0.008%, the rest is Fe and inevitable element.The transverse yield strength of the steel plate of the present application is 480MPa or more, the tensile strength is 610MPa or more, the yield ratio is less than 0.80, the elongation A 50mm ≥39%, the transverse-40 ℃ impact energy is 220J or more, according to ASTM-G111 corrosion standard, the average corrosion rate in carbon dioxide environment is <0.15mm / a.

The application discloses a carbon-based coating of a fuel cell metal bipolar plate and a preparation method thereof. The carbon-based structure coating of the metal bipolar plate comprises, from top to bottom, a conductive functional amorphous carbon layer, a compact amorphous carbon corrosion barrier layer and a flexible metal Ti transition layer. The flexible metal Ti transition layer is prepared by a magnetron sputtering process, the sputtering target material is pure metal Ti, and the thickness of the flexible metal Ti transition layer is 100 nm. The carbon material is used as the main body of the coating, so that the preparation cost of the protective coating can be effectively reduced. The amorphous carbon coating prepared by the magnetic filtering cathode vacuum arc technology and the cathode vacuum arc technology can effectively shorten the deposition time and improve the production efficiency. After the prepared carbon-based protective coating is subjected to constant potential corrosion at 0.6 V for 7200 min, the surface morphology of the coating does not change, and the contact resistance of the coating still meets the use standard.

The invention relates to manufacturing of a pipeline steel hot-rolled coiled plate for a longitudinal welded pipe, in particular to 450MPa-grade low-yield-ratio carbon dioxide corrosion resistant steel and a manufacturing method thereof. The steel comprises the following chemical components: less than or equal to 0.020% of C, Si, Mn, less than or equal to 0.020% of P, less than or equal to 0.002% of S, less than or equal to 0.008% of Cr, Cu, Nb, Ti, Al, Zr, less than or equal to 0.008% of N and the balance of Fe and inevitable elements. According to the steel plate, the transverse yield strength is 480 MPa or above, the tensile strength is 610 MPa or above, the yield ratio is lower than 0.80, the elongation A50 mm is larger than or equal to 39%, the transverse impact energy at-40 DEG C is 220 J or above, and the average corrosion rate in the carbon dioxide environment is smaller than 0.15 mm / a according to the ASTM-G111 corrosion standard.