Tungsten-containing maraging ultrahigh-strength steel and preparation method thereof

Abstract

The invention relates to the technical field of steel and iron materials, and discloses tungsten-containing maraging ultrahigh-strength steel and a preparation method thereof. The tungsten maraging ultrahigh-strength steel comprises, by mass, 14.5%-16.0% of Co, 17.0%-18.0% of Ni, 6.0%-8.0% of Mo, 1.0%-1.5% of Ti, 0.5%-1.0% of W and the balance Fe and inevitable impurities, and the impurity elements are controlled according to the requirements that C is smaller than or equal to 0.008%, Si is smaller than or equal to 0.1%, Mn is smaller than or equal to 0.1%, P is smaller than or equal to 0.005%, S is smaller than or equal to 0.005%, N is smaller than or equal to 0.0015%, and O is smaller than or equal to 0.0015%. Based on calculation and research results of a first principle that element doping influences a precipitated phase in the maraging steel, 0.5-1.0% of W element is added into a component system of the maraging steel, meanwhile, the content of Mo element in the steel is increased, and under the condition that the grain size of the steel is larger than or equal to 8.0 level, the tensile strength Rm is larger than or equal to 2800MPa, and the elongation A is larger than or equal to 5%.

Description

Technical Field

[0001] The invention relates to the technical field of steel materials, and in particular to a tungsten-containing martensitic aging ultra-high strength steel and a preparation method thereof. Background Art

[0002] Maraging steel has ultra-high strength and high plasticity, and is widely used in aerospace and communications. The dimensions of materials such as bars, wires, and plates have a great influence on performance, and the requirements for material dimensions vary greatly in different fields. Therefore, it is urgent to develop maraging steel that meets ultra-high strength and high plasticity (strength ≥ 2800MPa, elongation ≥ 5.0%) under different dimensions.

[0003] There are some problems with the preparation methods in the prior art. For example, CN 115558853 A discloses a high-strength and tough maraging steel and a preparation method thereof. By adding trace amounts of Nb and Ce, the electroslag remelting process required by the conventional process is omitted to prepare a high-strength and tough maraging steel. However, the method of this patent requires cold rolling of the material to obtain the strength, and the process is long. At the same time, the strength of its maraging steel is closely related to the material size: for materials with a diameter of ≥8.0mm, the tensile strength Rm<2500MPa. CN 115786813 A discloses a maraging steel plate and a preparation method thereof. This patent increases the strength of the steel by increasing the Mo content of the maraging steel and adding Al elements. The plate thickness is made 0.5mm~2mm by hot rolling + cold rolling, and the grain size reaches 9.5~11.5 levels to ensure strong plasticity. However, this method has great restrictions on the final shape and specifications of the steel.

[0004] Therefore, there is a need in the prior art for improving tungsten-containing martensitic aging ultra-high strength steel and its preparation method. Summary of the invention

[0005] In view of this, the purpose of the embodiment of the present invention is to provide a tungsten-containing maraging ultra-high strength steel and a preparation method thereof. Based on the first-principles calculation and research results of the influence of element doping on the precipitation phase in maraging steel, 0.5-1.0% of W element is added to the maraging steel component system, and the Mo element content in the steel is increased, so that the steel has a tensile strength Rm≥2800MPa and an elongation A≥5% when the grain size is ≥8.0.

[0006] Based on the above purpose, an embodiment of the present invention provides a tungsten-containing martensitic aged ultra-high strength steel, characterized in that, in terms of mass percentage, it includes: Co 14.5-16.0%, Ni 17.0-18.0%, Mo 6.0-8.0%, Ti 1.0-1.5%, W 0.5-1.0%, and the balance is Fe and unavoidable impurities, and the impurity element control requirements are: C≤0.008%, Si≤0.1%, Mn≤0.1%, P≤0.005%, S≤0.005%, N≤0.0015%, and O≤0.0015%.

[0007] In another aspect, the present invention provides a method for preparing tungsten-containing martensitic aging ultra-high strength steel, comprising the following steps: S1 prepares materials according to the composition of tungsten-containing maraging ultra-high strength steel, adopts vacuum induction and vacuum consumable dual process, and smelts maraging steel ingots; S2 performs high temperature homogenization treatment on the steel ingot; S3 adopts three-upsetting and three-drawing process to forge and blank the steel ingot to obtain forging material; S4 reheats the forged material and then performs precision forging or rolling to the target size; S5 heat treats and ages the rolled forging material to obtain martensitic aged ultra-high strength steel.

[0008] In some embodiments, in S2, the high temperature homogenization treatment includes: a temperature range of 1250°C to 1260°C, a holding time of 36h to 48h, and after the holding is completed, the forging is performed after the furnace is taken out and cooled to the forging temperature.

[0009] In some embodiments, in S3, the three-upsetting and three-drawing process includes: each upsetting reduction is ≥50%, and each drawing ratio is ≥200%.

[0010] In some embodiments, during forging, the start forging temperature is 1180~1200℃. When the temperature is lower than 1050℃, the steel is returned to the furnace and heated at 1150℃ for 2h before continuing the upsetting. The final forging temperature is ≥1000℃. When the temperature is lower than 1000℃, the steel is returned to the furnace and heated at 1100℃ for 2h before continuing the upsetting.

[0011] In some embodiments, in S4, the forging material is reheated to 1150°C and kept at this temperature for 2 hours, the single pass reduction of the fine forging or rolling is ≤35%, and the final forging or final rolling temperature is ≥950°C.

[0012] In some embodiments, in S5, the heat treatment process includes: Keep at 850~860℃ for 1~2 hours, then immediately cool to room temperature; Keep at 820~830℃ for 1~1.5 hours, then immediately cool to room temperature, repeat twice; Deep freezing treatment within 4 hours and then natural warming in the air; The material that has stabilized to room temperature within 8 hours is subjected to aging treatment.

[0013] In some embodiments, the cryogenic treatment includes: controlling the temperature to -70 to -80°C, and placing the forged material in a cryogenic device for cooling for 1 to 2 hours.

[0014] In some embodiments, the aging treatment includes: a treatment temperature of 480-500° C. and a treatment time of 5-8 hours.

[0015] In some embodiments, S1 further includes: performing a peeling treatment on the maraging steel ingot obtained by smelting.

[0016] The present invention has at least the following beneficial technical effects: By increasing the Mo element content and adding the W element, the amount of precipitated phases is increased and the precipitation strengthening effect is improved. At the same time, the brittleness of Ni3Ti can be alleviated by doping; and the Ni element content is increased to improve the plasticity and toughness of the steel. The steel made using the components and methods of the present invention has a tensile strength Rm≥2800MPa and an elongation A≥5% when the grain size is ≥8.0, and there is no strict restriction on the final external dimensions of the material.

[0017] The preparation method of the present invention does not require cold rolling, and the preparation process can be optimized. In addition, the room temperature deformation processing of high-alloy ultra-high strength steel is difficult, and the risk of cold rolling cracking is greatly reduced without the cold rolling process, and it is easy to prepare for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of an embodiment of a method for preparing tungsten-containing martensitic aged ultra-high strength steel provided by the present invention. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0021] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions; the terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects rather than to describe a specific order. "Multiple" means two or more, unless otherwise clearly and specifically defined.

[0022] In addition, reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] On the one hand, the present invention provides a tungsten-containing martensitic aging ultra-high strength steel, which includes, by mass percentage, Co14.5-16.0%, Ni17.0-18.0%, Mo6.0-8.0%, Ti1.0-1.5%, W0.5-1.0%, the balance is Fe and unavoidable impurities, and the impurity element control requirements are: C≤0.008%, Si≤0.1%, Mn≤0.1%, P≤0.005%, S≤0.005%, N≤0.0015%, O≤0.0015%.

[0024] The present invention adopts carbon-free steel (ultra-low carbon), eliminates the C element in the steel as much as possible, controls the C element to be below 0.008%, increases the Mo element content and adds the W element to increase the amount of precipitated phases and improve the precipitation strengthening effect, and at the same time, the brittleness of Ni3Ti can be alleviated by doping; and the Ni element content is increased to improve the plasticity and toughness of the steel.

[0025] Another aspect of the present invention further provides a method for preparing tungsten-containing martensitic aging ultra-high strength steel, comprising the following steps: S1 prepares materials according to the composition of tungsten-containing maraging ultra-high strength steel, adopts vacuum induction and vacuum consumable dual process, and smelts maraging steel ingots; S2 performs high temperature homogenization treatment on the steel ingot; S3 adopts three-upsetting and three-drawing process to forge and blank the steel ingot to obtain forging material; S4 reheats the forged material and then performs precision forging or rolling to the target size; S5 heat treats and ages the rolled forging material to obtain martensitic aged ultra-high strength steel.

[0026] In some embodiments, in S2, the high temperature homogenization treatment includes: a temperature range of 1250°C to 1260°C, a holding time of 36h to 48h, and after the holding is completed, the forging is performed after the furnace is taken out and cooled to the forging temperature.

[0027] In some embodiments, in S3, the three-upsetting and three-drawing process includes: each upsetting reduction is ≥50%, and each drawing ratio is ≥200%; In some embodiments, during forging, the start forging temperature is 1180~1200℃. When the temperature is lower than 1050℃, the steel is returned to the furnace and heated at 1150℃ for 2h before continuing the upsetting. The final forging temperature is ≥1000℃. When the temperature is lower than 1000℃, the steel is returned to the furnace and heated at 1100℃ for 2h before continuing the upsetting.

[0028] In some embodiments, in S4, the forging material is reheated to 1150°C and kept at this temperature for 2 hours, the single pass reduction of the fine forging or rolling is ≤35%, and the final forging or final rolling temperature is ≥950°C.

[0029] In some embodiments, in S5, the heat treatment process includes: Keep at 850~860℃ for 1~2 hours, then immediately cool to room temperature; Keep at 820~830℃ for 1~1.5 hours, then immediately cool to room temperature, repeat twice; Deep freezing treatment within 4 hours and then natural warming in the air; The material that has stabilized to room temperature within 8 hours is subjected to aging treatment.

[0030] In some embodiments, the cryogenic treatment includes: controlling the temperature to -70 to -80°C, and placing the forged material in a cryogenic device for cooling for 1 to 2 hours.

[0031] In some embodiments, the aging treatment includes: a treatment temperature of 480-500° C. and a treatment time of 5-8 hours.

[0032] In some embodiments, S1 further includes: performing a peeling treatment on the maraging steel ingot obtained by smelting.

[0033] Based on the first principle calculation and research results of the influence of element doping on the precipitation phase in maraging steel, the present invention adds 0.5-1.0% of W element to the maraging steel composition system, dopes Ni3Ti precipitation phase into it during the aging treatment process, increases the number of precipitation phases, and improves the brittleness of the precipitation phase; at the same time, increases the Mo element content in the steel, so that the steel has a tensile strength Rm≥2800MPa and an elongation A≥5% when the grain size is ≥8.0. This material can be widely used in the fields of aerospace and 3C electronics, and this material design method can be widely used in the design of maraging steels with other personalized mechanical properties, and has broad application prospects.

[0034] Example 1 This embodiment provides a tungsten-containing martensitic aging ultra-high strength steel and a preparation method thereof, and the specific steps are as follows: Step 1: Vacuum Smelting The vacuum induction and vacuum consumable dual process is adopted to smelt a martensitic aged steel ingot; and the ingot is subjected to a peeling treatment.

[0035] The alloy element composition of the maraging steel ingot is: Co 15.5%, Ni 17.7%, Mo 7.12%, Ti 1.45%, W 0.5%, and the balance is Fe and unavoidable impurities.

[0036] The content of key impurity elements is: C 0.003%, Si 0.01%, Mn 0.01%, P 0.0018%, S 0.0010%, N 0.0010%, O 0.0012%.

[0037] Step 2: High temperature homogenization The maraging steel ingot after the peeling treatment is placed in a heating furnace with a furnace temperature of 1000° C. and subjected to high-temperature homogenization treatment as the furnace is heated.

[0038] The homogenization treatment conditions include: a holding temperature of 1250°C, a holding time of 48 hours, and after the holding is completed, the steel is taken out of the furnace and cooled to a forging temperature of 1200°C before forging and blanking.

[0039] Step 3: Forging The forging process adopts "three upsetting and three drawing" with a forging temperature of 1200℃, the first upsetting reduction is 55%, and the drawing rate is 250%; the second upsetting reduction is 55%, and the drawing rate is 250%; the third upsetting reduction is 50%, and the drawing rate is 200%. The blank is opened into a round bar with a diameter of φ300mm.

[0040] Step 4: Heat Deformation The round bar forging material after the above-mentioned "three upsetting and three drawing" blanking is returned to the furnace and heated to 1150℃, and kept at this temperature for 2 hours. Then it is taken out of the furnace for fine forging, with a reduction of 30% in the first pass of fine forging and 10% in the subsequent passes, and finally a round bar with a diameter of φ50mm is obtained, and the final forging temperature of fine forging is 960℃.

[0041] Step 5: Heat Treatment The heat treatment process is: keep warm at 860℃ for 1 hour, then immediately cool to room temperature with oil; keep warm at 820℃ for 1 hour, then immediately cool to room temperature with oil, repeat twice; cool in a -73℃ deep freezer for 1.5 hours within 4 hours, then take out of the deep freezer and allow to warm up naturally in the air; age the material that has stabilized to room temperature for 8 hours, with an aging temperature of 485℃ and a time of 5 hours. Example 2 This embodiment provides a tungsten-containing martensitic aging ultra-high strength steel and a preparation method thereof, and the specific steps are as follows: Step 1: Vacuum Smelting The vacuum induction and vacuum consumable dual process is adopted to smelt a martensitic aged steel ingot; and the ingot is subjected to a peeling treatment.

[0042] The alloy element composition of the maraging steel ingot is: Co 16.0%, Ni 18.0%, Mo 7.80%, Ti 1.10%, W 0.7%, and the balance is Fe and inevitable impurities.

[0043] The key impurity element contents are: C 0.002%, Si 0.02%, Mn 0.01%, P 0.0015%, S 0.0012%, N 0.0007%, O 0.0010%.

[0044] Step 2: High temperature homogenization The maraging steel ingot after the peeling treatment is placed in a heating furnace with a furnace temperature of 1000° C. and subjected to high-temperature homogenization treatment as the furnace is heated.

[0045] The homogenization treatment conditions include: a holding temperature of 1280°C, a holding time of 36 hours, and after the holding is completed, the furnace is taken out of the furnace and cooled to the forging temperature of 1200°C before forging and blanking.

[0046] Step 3: Forging The forging process adopts "three upsetting and three drawing" with a forging temperature of 1200℃, a 60% upsetting reduction and a 300% drawing rate for the first upsetting, a 55% upsetting reduction and a 250% drawing rate for the second upsetting, and a 50% upsetting reduction and a 200% drawing rate for the third upsetting. The length, width and height of the slab are 3000, 1000 and 500mm respectively.

[0047] Step 4: Heat Deformation The slab forgings after the above “three upsetting and three drawing” were returned to the furnace and heated to 1150℃, and kept at this temperature for 2 hours. Then they were rolled out of the furnace, with the first rolling pass reducing by 20%, and the subsequent passes reducing by 10%, and finally a plate with a thickness of 20mm was obtained, and the final rolling temperature was 950℃.

[0048] Step 5: Heat Treatment The heat treatment process is: keep warm at 850℃ for 2 hours, then immediately oil cool to room temperature; keep warm at 820℃ for 1 hour, then immediately oil cool to room temperature, repeat twice; place in -73℃ deep freezing device to cool for 2 hours within 4 hours, then take out of the deep freezing device and naturally warm up in the air; age the material that has stabilized to room temperature within 8 hours, with an aging temperature of 480℃ and a time of 7 hours. Comparative Example 1 This embodiment provides a tungsten-containing martensitic aging ultra-high strength steel and a preparation method thereof, and the specific steps are as follows: Step 1: Vacuum Smelting The vacuum induction and vacuum consumable dual process is adopted to smelt a martensitic aged steel ingot; and the ingot is subjected to a peeling treatment.

[0049] The alloy element composition of the maraging steel ingot is: Co 12.0%, Ni 18.2%, Mo 4.53%, Ti 1.43%, Al 0.12%, and the balance is Fe and unavoidable impurities.

[0050] The key impurity element contents are: C 0.0011%, Si 0.009%, Mn 0.01%, P 0.0013%, S 0.0016%, N 0.0011%, and O 0.0008%.

[0051] Step 2: High temperature homogenization The maraging steel ingot after the peeling treatment is placed in a heating furnace with a furnace temperature of 1000° C. and subjected to high-temperature homogenization treatment as the furnace is heated.

[0052] The homogenization treatment conditions include: a holding temperature of 1250°C, a holding time of 48 hours, and after the holding is completed, the steel is taken out of the furnace and cooled to a forging temperature of 1200°C before forging and blanking.

[0053] Step 3: Forging The forging process adopts "three upsetting and three drawing" with a forging temperature of 1200℃, the first upsetting reduction is 55%, and the drawing rate is 250%; the second upsetting reduction is 55%, and the drawing rate is 250%; the third upsetting reduction is 50%, and the drawing rate is 200%. The blank is opened into a round bar with a diameter of φ300mm.

[0054] Step 4: Heat Deformation The round bar forging material after the above-mentioned "three upsetting and three drawing" blanking is returned to the furnace and heated to 1150℃, and kept at this temperature for 2 hours. Then it is taken out of the furnace for fine forging, with a reduction of 30% in the first pass of fine forging and 10% in the subsequent passes, and finally a round bar with a diameter of φ50mm is obtained, and the final forging temperature of fine forging is 960℃.

[0055] Step 5: Heat Treatment The heat treatment process is: keep warm at 860℃ for 1 hour, then immediately cool to room temperature with oil; keep warm at 820℃ for 1 hour, then immediately cool to room temperature with oil, repeat twice; cool in a -73℃ deep freezer for 1.5 hours within 4 hours, then take out of the deep freezer and allow to warm up naturally in the air; age the material that has stabilized to room temperature for 8 hours, with an aging temperature of 485℃ and a time of 5 hours. Comparative Example 2 This embodiment provides a tungsten-containing martensitic aging ultra-high strength steel and a preparation method thereof, and the specific steps are as follows: Step 1: Vacuum Smelting The vacuum induction and vacuum consumable dual process is adopted to smelt a martensitic aged steel ingot; and the ingot is subjected to a peeling treatment.

[0056] The alloy element composition of the maraging steel ingot is: Co 11.96%, Ni 18.18%, Mo 4.46%, Ti 1.39%, Al 0.14%, and the balance is Fe and unavoidable impurities.

[0057] The content of key impurity elements is: C 0.0027%, Si 0.014%, Mn 0.012%, P 0.0013%, S 0.0016%, N 0.0005%, O 0.0006%.

[0058] Step 2: High temperature homogenization The maraging steel ingot after the peeling treatment is placed in a heating furnace with a furnace temperature of 1000° C. and subjected to high-temperature homogenization treatment as the furnace is heated.

[0059] The homogenization treatment conditions include: a holding temperature of 1280°C, a holding time of 36 hours, and after the holding is completed, the furnace is taken out of the furnace and cooled to the forging temperature of 1200°C before forging and blanking.

[0060] Step 3: Forging The forging process adopts "three upsetting and three drawing" with a forging temperature of 1200℃, a 60% upsetting reduction and a 300% drawing rate for the first upsetting, a 55% upsetting reduction and a 250% drawing rate for the second upsetting, and a 50% upsetting reduction and a 200% drawing rate for the third upsetting. The length, width and height of the slab are 3000, 1000 and 500mm respectively.

[0061] Step 4: Heat Deformation The slab forgings after the above “three upsetting and three drawing” were returned to the furnace and heated to 1150℃, and kept at this temperature for 2 hours. Then they were rolled out of the furnace, with the first rolling pass reducing by 20%, and the subsequent passes reducing by 10%, and finally a plate with a thickness of 20mm was obtained, and the final rolling temperature was 950℃.

[0062] Step 5: Heat Treatment The heat treatment process is: keep warm at 850℃ for 2 hours, then immediately oil cool to room temperature; keep warm at 820℃ for 1 hour, then immediately oil cool to room temperature, repeat twice; place in -73℃ deep freezing device to cool for 2 hours within 4 hours, then take out of the deep freezing device and naturally warm up in the air; age the material that has stabilized to room temperature within 8 hours, with an aging temperature of 510℃ and a time of 3 hours.

[0063] The mechanical properties of the maraging steel obtained in the examples and comparative examples after aging are as follows: Table 1 Mechanical properties of maraging steel obtained in Examples and Comparative Examples after aging

[0064] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

[0065] By means of the tungsten-containing maraging ultra-high strength steel and the preparation method thereof provided by the present invention, ultra-high strength steel with a strength Rm≥2800MPa and an elongation A≥5.0% or more can be obtained; and the preparation process is relatively simple, and the cold rolling process required by the prior art is not required, which can greatly improve the stability of industrial preparation and the product yield rate; at the same time, the present invention has no strict restrictions on the final external dimensions of the maraging steel product, and the material described in the present invention can be used in a variety of fields and service scenarios, which has important practical significance.

[0066] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope disclosed in the embodiments of the present invention as defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0067] It should be understood that, as used herein, the singular forms "a", "an" are intended to include the plural forms as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations including one or more of the associated listed items.

[0068] The serial numbers of the embodiments disclosed in the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0069] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A tungsten-containing martensitic aging ultra-high strength steel, characterized in that: Calculated by mass percentage, it includes Co 14.5-16.0%, Ni 17.0-18.0%, Mo 6.0-8.0%, Ti 1.0-1.5%, W 0.5-1.0%, and the balance is Fe and unavoidable impurities. The impurity elements are controlled as follows: C≤0.008%, Si≤0.1%, Mn≤0.1%, P≤0.005%, S≤0.005%, N≤0.0015%, and O≤0.0015%.

2. A method for preparing the tungsten-containing martensitic aging ultra-high strength steel according to claim 1, characterized in that: include: S1 prepares materials according to the composition of tungsten-containing maraging ultra-high strength steel, adopts vacuum induction and vacuum consumable dual process, and smelts maraging steel ingots; S2 performs high temperature homogenization treatment on the steel ingot; S3 adopts a three-upsetting and three-drawing process to forge the steel ingot to obtain a forged material; S4: reheating the forged material and then performing precision forging or rolling to a target size; S5 heat treats and ages the rolled forging material to obtain martensitic aged ultra-high strength steel.

3. The method for preparing tungsten-containing martensitic aged ultra-high strength steel according to claim 2, characterized in that: In S2, the high temperature homogenization treatment includes: a temperature range of 1250°C to 1260°C, a holding time of 36h to 48h, and after the holding is completed, the steel is taken out of the furnace and cooled to the forging temperature before forging and blanking.

4. The method for preparing tungsten-containing martensitic aging ultra-high strength steel according to claim 2, characterized in that: In S3, the three-upsetting and three-drawing process includes: each upsetting reduction is ≥50%, and each drawing ratio is ≥200%.

5. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 4, characterized in that: During forging, the starting forging temperature is 1180~1200℃. When the temperature is lower than 1050℃, return to the furnace and heat at 1150℃ for 2h before continuing upsetting; the final forging temperature is ≥1000℃. When the temperature is lower than 1000℃, return to the furnace and heat at 1100℃ for 2h before continuing upsetting.

6. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 2, characterized in that: In S4, the forging material is reheated to 1150°C and kept at this temperature for 2 hours. The single pass reduction of the fine forging or rolling is ≤35%, and the final forging or final rolling temperature is ≥950°C.

7. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 2, characterized in that: In S5, the heat treatment process includes: Keep at 850~860℃ for 1~2 hours, then immediately cool to room temperature; Keep at 820-830℃ for 1-1.5 hours, then immediately cool to room temperature, repeat twice; Deep freezing treatment within 4 hours and then natural warming in the air; The material that has stabilized to room temperature within 8 hours is subjected to aging treatment.

8. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 7, characterized in that: The cryogenic treatment comprises: controlling the temperature to -70--80°C, placing the forging material in a cryogenic device and cooling it for 1-2 hours.

9. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 7, characterized in that: The aging treatment includes: a treatment temperature of 480-500° C. and a treatment time of 5-8 hours.

10. The method for preparing tungsten-containing maraging ultra-high strength steel according to claim 2, characterized in that: S1 also includes: peeling the maraging steel ingot obtained by smelting.

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