Alloy steel part and machining process thereof, folding hinge and folding type electronic equipment

Abstract

The invention relates to an alloy steel part and a machining process thereof, a folding hinge and folding type electronic equipment. The machining technology of the alloy steel part comprises the steps that alloy powder and an adhesive are mixed, feeding particles are obtained, and the alloy powder comprises carbon, chromium, nickel, molybdenum, manganese, silicon, vanadium, cobalt and iron; carrying out an injection molding process on the feeding particles to obtain a green body; the green body is subjected to an adhesive removing process, and a formed blank is obtained; and carrying out a heat treatment process on the formed blank to obtain the alloy steel part.

Description

Technical Field

[0001] The present disclosure relates to the field of terminal technology, and in particular to an alloy steel part and a processing technology thereof, a folding hinge and a folding electronic device. Background Art

[0002] Foldable models are easy to carry and can expand the screen size, making them a place in the high-end model market. However, foldable models need to be unfolded to achieve multi-screen collaborative display and folded to achieve storage, which increases the wear resistance and strength requirements of the hinge parts in foldable models. Summary of the invention

[0003] The present invention provides an alloy steel part and a processing technology thereof, a folding hinge and a folding electronic device to solve the deficiencies in the related art.

[0004] According to a first aspect of an embodiment of the present disclosure, a processing technology for an alloy steel part is provided, comprising:

[0005] Mixing alloy powder and a binder to obtain feed particles, wherein the alloy powder comprises carbon, chromium, nickel, molybdenum, manganese, silicon, vanadium, cobalt and iron;

[0006] The feed particles are subjected to an injection molding process to obtain a green body;

[0007] Performing a process of removing the binder from the green body to obtain a formed body;

[0008] The formed blank is subjected to a heat treatment process to obtain the alloy steel part.

[0009] Optionally, the mixing of the alloy powder and the binder to obtain feed particles comprises:

[0010] obtaining alloy powder and binder respectively;

[0011] Selecting spherical or nearly spherical alloy powder and the binder according to a target mass ratio, adding them into a mixer for mixing;

[0012] The mixed metal powder and binder are output from the mixer in multiple stages to obtain the feed particles.

[0013] Optionally, obtaining alloy powder includes:

[0014] Obtaining single substance powders corresponding to each chemical element contained in the alloy powder;

[0015] The alloy powder is obtained by mixing the single substance powders corresponding to the chemical elements according to the weight percentage of the chemical elements in the alloy powder.

[0016] Optionally, the mixing temperature of the alloy powder and the binder in the mixer is greater than or equal to 180° C. and less than or equal to 220° C., and the mixing time is greater than or equal to 2.5 h and less than or equal to 3.5 h.

[0017] Optionally, a target mass ratio of the alloy powder to the binder is within a range of 8.5:1-9:1.

[0018] Optionally, the weight percentage of each chemical element in the alloy powder is as follows:

[0019] The weight percentage of carbon element is greater than or equal to 1.35% and less than or equal to 1.56%;

[0020] The weight percentage of chromium is greater than or equal to 5.5% and less than or equal to 7.5%;

[0021] The weight percentage of nickel element is greater than or equal to 0.36% and less than or equal to 0.7%;

[0022] The weight percentage of molybdenum element is greater than or equal to 0.6% and less than or equal to 1.05%;

[0023] The weight percentage of manganese is greater than or equal to 0.25% and less than or equal to 0.44%;

[0024] The weight percentage of silicon is greater than or equal to 0.15% and less than or equal to 0.62%;

[0025] The weight percentage of vanadium is less than or equal to 0.1%;

[0026] The weight percentage of cobalt element is less than or equal to 0.1%;

[0027] The rest is iron and impurity elements that cannot be completely eliminated.

[0028] Optionally, the particle size of the alloy powder is greater than or equal to 10 microns and less than or equal to 30 microns.

[0029] Optionally, the binder includes a paraffin matrix, stearic acid and at least two of the following chemicals:

[0030] Polystyrene, polypropylene, high-density polyethylene and low-density polyethylene.

[0031] Optionally, the mass percentage of stearic acid in the binder is greater than or equal to 1% and less than or equal to 5%.

[0032] Optionally, the step of subjecting the feed particles to an injection molding process to obtain a green body comprises:

[0033] Adding the feed particles into an injection machine;

[0034] Injecting the feed particles into a target mold for molding at an injection temperature within a range of 95° C. to 115° C. and an injection pressure within a range of 110 MPa to 130 MPa;

[0035] The target mold is separated to obtain the green body.

[0036] Optionally, the process of removing the binder from the green body to obtain a formed body comprises:

[0037] The green body is put into a degreasing furnace for degreasing to obtain a brown body;

[0038] The brown blank is added into a sintering machine for sintering and solidification to obtain the molded blank.

[0039] Optionally, the step of adding the green body into a degreasing furnace for degreasing to obtain a brown body comprises:

[0040] The degreasing temperature in the degreasing furnace is controlled within the range of 105°C-112°C, and nitric acid at a flow rate of 30g / h-45g / h and nitrogen at a flow rate of 400L / h-450L / h are introduced simultaneously to perform degreasing under the conditions of the degreasing furnace to obtain the brown blank.

[0041] Optionally, adding the brown blank into a sintering machine for sintering and curing to obtain the molded blank comprises:

[0042] Under the condition that the sintering temperature is controlled within the range of 1235° C.-1250° C., the sintering time is 180 min-200 min to obtain the molded blank.

[0043] Optionally, the heat treatment process is performed on the formed blank to obtain the alloy steel part, including:

[0044] Performing quenching treatment on the formed blank;

[0045] The formed blank after quenching is subjected to tempering treatment to obtain the alloy steel part.

[0046] Optionally, the temperature of the quenching treatment is in the range of 510° C.-570° C., and the holding time of the tempering treatment is in the range of 11 h-13 h.

[0047] According to a second aspect of the embodiments of the present disclosure, there is provided an alloy steel part formed by the processing technology described in any one of the above embodiments.

[0048] According to a third aspect of the embodiments of the present disclosure, there is provided a folding hinge, comprising at least one alloy steel part as described in any one of the embodiments above, wherein when the folding hinge comprises a plurality of the alloy steel parts, the plurality of alloy steel parts are arranged in the same shape or in a plurality of shapes.

[0049] Optionally, at least the alloy steel part is used to achieve suspension of the folding hinge.

[0050] According to a fourth aspect of the embodiments of the present disclosure, there is provided a foldable electronic device, comprising a folding hinge as described in any one of the above embodiments.

[0051] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0052] It can be seen from the above embodiments that the addition of nickel, vanadium and cobalt elements to the alloy steel parts disclosed in the present invention, combined with the subsequent heat treatment process of the formed skin, can improve the strength and wear resistance of the alloy steel parts. When the alloy steel parts are subsequently used in electronic equipment, it is beneficial to extend the service life of the alloy steel parts and the electronic equipment.

[0053] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0055] Figure 1 The present invention is a process flow chart of a processing of an alloy steel part according to an exemplary embodiment.

[0056] Figure 2 is a process flow chart of another type of alloy steel part according to an exemplary embodiment.

[0057] Figure 3 It is a comparison chart of strength parameters of alloy steel parts disclosed in the present invention and existing materials.

[0058] Figure 4 It is a comparison chart of wear resistance parameters of alloy steel parts disclosed in the present invention and existing materials. DETAILED DESCRIPTION

[0059] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0060] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0061] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0062] In order to meet consumers' demands for screen ratios and diversified functions of electronic devices, foldable electronic devices are gradually appearing in the public eye. Since foldable electronic devices need to be opened and closed many times and frequently in actual application scenarios, higher wear resistance requirements are put forward for the hinges that realize the folding of electronic devices, and in order to ensure the reliability and stability of folding, certain requirements are also placed on the strength of the hinges.

[0063] Figure 1 The present invention is a processing technology of an alloy steel part according to an exemplary embodiment. The alloy steel part formed by the processing technology can be used to prepare electronic devices, especially the processing and forming of related parts in foldable electronic devices. Figure 1 As shown, the processing technology may include the following steps:

[0064] In step 101, alloy powder and a binder are mixed to obtain feed particles.

[0065] In this embodiment, the component materials of the alloy powder may include elements, chromium elements, nickel elements, molybdenum elements, manganese elements, silicon elements, vanadium elements, cobalt elements and iron elements. For obtaining the alloy powder, the corresponding single element powder can be first obtained according to the chemical element composition of the alloy powder, and then a plurality of single element powders are mixed to obtain the alloy powder. For each single element powder, it can be prepared by atomization or mixed alloy centrifugation. The binder can be a conventional organic binder. The addition of the binder can improve the bonding degree between the alloy powders, ensure that the feed particles obtained later will not be loose and not formed, and facilitate the smooth progress of the subsequent injection molding process.

[0066] Among them, carbon can play a role in solid solution strengthening, which can improve the strength and hardness of alloy steel parts. Chromium is conducive to uniform action inside the alloy steel parts in the subsequent heat treatment process to uniformly produce the corresponding chemical structure. Manganese can improve the strength and hardness of alloy steel parts, but the addition of manganese can easily cause the plasticity and toughness of alloy steel parts to decrease. Therefore, in order to improve the strength and hardness while reducing the impact on the plasticity and toughness of alloy steel parts, molybdenum is also added to the alloy steel parts so that the chemical structure of the alloy steel parts can maintain good plasticity and toughness.

[0067] In step 102, the feed particles are subjected to an injection molding process to obtain a green body.

[0068] In this embodiment, the feed particles can be added to the injection molding machine, and the feed particles can be injected into the target mold by the injection molding machine. After the green body after subsequent molding is separated from the target mold, a green body can be obtained. The target mold can be a single-cavity design, or the target mold can also be a multi-cavity setting to form multiple alloy steel parts by a single injection. The cavity size design of the target mold needs to take into account the shrinkage of the green body in the subsequent process.

[0069] In step 103, a process of removing the binder from the green body is performed to obtain a molded body.

[0070] In this embodiment, the binder added in step 101 is removed in this step to maintain the purity of the subsequent finished alloy steel part.

[0071] In step 104, the formed blank is subjected to a heat treatment process to obtain the alloy steel part.

[0072] In this embodiment, through the heat treatment process, the vanadium element in the alloy powder plays a role in refining the grains and improving the strength of the alloy steel parts. At the same time, the vanadium element and the carbon element can form a high melting point and stable dispersed carbide, which can effectively improve the wear resistance of the alloy steel parts. The cobalt element does not form a compound with the carbon element, and can be left in the alloy steel parts after the heat treatment is completed, thereby improving the strength and wear resistance of the alloy steel parts at high temperatures, so as to improve the stability of the alloy steel parts to maintain high strength and high wear resistance in various temperature scenarios. During the heat treatment process, the nickel element can expand the temperature range of austenite transformation, and can promote the stable formation of the final organization during the heat treatment process, thereby improving the strength of the alloy steel parts.

[0073] It can be seen from the above embodiments that the addition of nickel, vanadium and cobalt elements to the alloy steel parts of the present disclosure, combined with the subsequent heat treatment process of the formed skin, can improve the strength and wear resistance of the alloy steel parts. When the alloy steel parts are subsequently used in electronic equipment, it is beneficial to extend the service life of the alloy steel parts and the electronic equipment. In one embodiment of the present disclosure, the alloy steel of the present disclosure can also be called carbon ceramic steel.

[0074] In order to elaborate on the technical solution of the present disclosure, Figure 2 As shown, the processing technology of the alloy steel parts may include:

[0075] In step 201, single substance powders of each chemical element are obtained.

[0076] In this embodiment, an atomization method or a mixed alloy separation method can be used to obtain single substance powders of various chemical elements. Specifically, single substance powders of carbon, chromium, nickel, molybdenum, manganese, silicon, vanadium, cobalt and iron can be obtained.

[0077] In step 202, a plurality of single substance powders are mixed according to weight percentage to obtain alloy powder.

[0078] In this embodiment, the individual element powders may be mixed in proportion according to the weight percentage of each chemical element required in the pre-design to obtain the alloy powder.

[0079] For example, in some embodiments, the weight percentage of carbon is greater than or equal to 1.35% and less than or equal to 1.56%; the weight percentage of chromium is greater than or equal to 5.5% and less than or equal to 7.5%; the weight percentage of nickel is greater than or equal to 0.36% and less than or equal to 0.7%; the weight percentage of molybdenum is greater than or equal to 0.6% and less than or equal to 1.05%; the weight percentage of manganese is greater than or equal to 0.25% and less than or equal to 0.44%; the weight percentage of silicon is greater than or equal to 0.15% and less than or equal to 0.62%; the weight percentage of vanadium is less than or equal to 0.1%; the weight percentage of cobalt is less than or equal to 0.1%; the rest is iron and impurity elements that cannot be completely eliminated. In order to obtain 100g of alloy powder, the weight of the carbon element powder that can be added is in the range of 1.35g-1.56g. The weight of the chromium element powder is in the range of 5.5g-7.5g. The weight of the nickel powder is in the range of 0.36g-0.7g. The weight of the molybdenum powder is in the range of 0.5g-1.05g. The weight of the manganese powder is in the range of 0.25g-0.44g. The weight of the silicon powder is in the range of 0.15g-0.62g. The weight of the vanadium powder is less than or equal to 0.1g. The weight of the cobalt powder is less than or equal to 0.1g, and other iron powders and impurity elements that cannot be eliminated.

[0080] In this composition ratio, the carbon element can promote the formation of room temperature bainite structure, and at the same time, the bainite and ferrite are accumulated on the dislocation boundary, which increases the strength of the dislocation, so that wear notches are not easily generated during fatigue wear.

[0081] In step 203, spherical or approximately spherical alloy powder is selected.

[0082] After the single substance powders of each chemical element are fully mixed, a spherical or approximately spherical alloy powder can be selected through a filter, and then the spherical or approximately spherical alloy powder is mixed with a binder. The particle size of the alloy powder is greater than or equal to 10 microns and less than or equal to 30 microns. According to the particle size range, a suitable filter can be designed to select a spherical or approximately spherical alloy powder.

[0083] Spherical or nearly spherical alloy powders can ensure that the slope angle and friction contact area between the alloy powders are moderate, avoiding excessive contact area between the alloy powders that makes it difficult for the alloy powders to move, and at the same time avoiding too small a contact area that causes irregular movement of the alloy powders and localized aggregation of some components, affecting the uniformity of components in various parts of the alloy steel parts, and further affecting the strength and wear resistance of various areas of the alloy steel parts.

[0084] In step 204 , adhesive is obtained.

[0085] In this embodiment, the binder can be an organic binder, and the binder can be a mixture of multiple chemical substances. For example, the binder can include a paraffin matrix and stearic acid, and the binder can also include at least two chemical substances selected from polystyrene, polypropylene, high-density polyethylene, and low-density polyethylene. The above chemical substances can be mixed and then added to the selected alloy powder. Or the above chemical substances can be added to the alloy powder in sequence. Among them, the mass percentage of stearic acid in the binder is greater than or equal to 1% and less than or equal to 5%.

[0086] In step 205, the binder and the alloy powder are added into a mixer for mixing.

[0087] In this embodiment, the binder and the selected spherical or approximately spherical alloy powder can be added to the mixer for mixing according to the set target mass ratio between the binder and the alloy powder. For example, the target mass ratio between the binder and the alloy powder can be in the range of 8.5:1-9:1. Controlling the mass ratio of the binder to the alloy powder within this range can ensure that the binder can bond the alloy powders well, while avoiding the binder being too large, which increases the difficulty of the subsequent binder removal process.

[0088] In the process of mixing the binder and the alloy powder by the mixer, the binder and the alloy powder can be fully stirred so that the alloy powder can be bonded into a whole. The mixing temperature of the alloy powder and the binder in the mixer is greater than or equal to 180° C. and less than or equal to 220° C., and the mixing time is greater than or equal to 2.5 hours and less than or equal to 3.5 hours.

[0089] In step 206, the mixed alloy powder and binder are cut off and output from the mixer to obtain feed particles.

[0090] In this embodiment, after the binder and alloy powder are mixed and stabilized, the mixed metal powder and binder can be output from the mixer in multiple stages to obtain multiple feed particles, and each feed granulation can be used to form a single or multiple molded blanks. It can be that after the mixer mixes for a preset time, the binder and alloy powder are considered to be mixed and stabilized; or it can be determined by the production line personnel through experience or by instruments, and the specific operation can be performed as needed.

[0091] In step 207, feed pellets are added to the injection machine.

[0092] In this embodiment, the injection machine may include a vertical injection machine, and the user may manually add the feed particles into the injection machine, or add the feed particles into the injection machine through a machine. The feed particles added to the injection machine at a time may be one or more, and the specific design may be as required, and the present disclosure does not limit this.

[0093] In step 208, feed particles are injected into a target mold.

[0094] In this embodiment, the feed particles can be injected into the target mold for molding at an injection temperature within the range of 95°C-115°C and an injection pressure within the range of 110MPa-130MPa. The cavity of the target mold can be designed according to the shape requirements of the alloy steel part. For example, the alloy steel part is an alloy steel cam. The cavity of the current mold can be designed according to the various size parameters of the alloy steel cam. The same target mold can include a single or multiple cavities.

[0095] In step 209, the mold is separated to obtain a green body.

[0096] In this embodiment, demolding can be performed under appropriate conditions to obtain a green body.

[0097] In step 210, the green body is put into a degreasing furnace for degreasing to obtain a brown body.

[0098] In step 211, the brown blank is added into a sintering machine for sintering and solidification to obtain a molded blank.

[0099] In this embodiment, the green body can be added to a hot degreasing furnace for a degreasing process, and most of the binder can be removed. The remaining lower part of the binder can be used as a connecting skeleton between the alloy powders, so that the alloy powders can be added to the subsequent sintering machine as a solid whole for sintering and curing. At the same time, during the degreasing process, the green body has porosity, and channels are formed inside, which is conducive to gas flow and is conducive to the rapid discharge of the binder when it evaporates and decomposes during the subsequent sintering.

[0100] After the degreasing process is completed, in order to remove the remaining binder as the connecting skeleton, the brown blank can be added to the sintering machine for sintering and solidification. The brown blank is slowly heated under the protection of gas to remove the residual binder. After the binder is completely removed, the brown blank will be heated to a very high temperature, the gaps between the particles disappear due to the fusion of the particles, the brown blank will shrink to its designed size and turn into a dense solid, and the final product with a firm connection between the alloy powders will be obtained.

[0101] Among them, for the hot debinding process in the debinding furnace, the debinding temperature in the debinding furnace is controlled within the range of 105°C-112°C, and nitric acid with a flow rate of 30g / h-45g / h and nitrogen with a flow rate of 400L / h-450L / h are introduced at the same time to perform debinding under the conditions of the debinding furnace to obtain the brown blank. For the sintering and curing process, the brown blank is sintered for 180min-200min under the condition that the sintering temperature is controlled within the range of 1235°C-1250°C to obtain the molded blank.

[0102] In step 212, the preform is quenched.

[0103] In step 213, the formed blank is subjected to tempering after the quenching treatment.

[0104] In this embodiment, by quenching and tempering the formed blank, the vanadium element in the alloy powder plays a role in refining the grains and improving the strength of the alloy steel parts. At the same time, the vanadium element and the carbon element can form a high melting point and stable dispersed carbide, which can effectively improve the wear resistance of the alloy steel parts. The cobalt element does not form a compound with the carbon element, and can be left in the alloy steel parts after the heat treatment is completed, thereby improving the strength and wear resistance of the alloy steel parts at high temperatures, so as to improve the stability of the alloy steel parts to maintain high strength and high wear resistance in various temperature scenarios. During the heat treatment process, the nickel element can expand the temperature range of austenite transformation, and can promote the stable formation of the final organization during the heat treatment process, thereby improving the strength of the alloy steel parts. Among them, the temperature of the quenching treatment is in the range of 510℃-570℃, the holding time of the tempering treatment is in the range of 11h-13h, and the alloy steel parts are subsequently cooled in a certain way.

[0105] In step 214, after the tempering treatment is completed, an alloy steel part is obtained.

[0106] See also Figure 3 The table shown in the figure compares the tensile strength, yield strength, elongation and tensile modulus of alloy steel parts No. 1, alloy steel parts No. 2, alloy steel parts No. 3, existing materials No. 1 and existing materials No. 2. It can be seen from the comparison that although existing materials No. 1 and No. 2 can maintain good tensile strength and yield strength, the elongation of the materials is poor, and the tensile modulus is not very high. However, alloy steel parts No. 1 and alloy steel parts No. 3 in the present disclosure can maintain good tensile strength and yield strength on the one hand, while elongation and tensile modulus are better. It can be seen that the comprehensive strength conditions of alloy steel parts in the present disclosure are better than those of existing materials, showing good strength parameters.

[0107] See also Figure 4The table shown compares the weight loss and wear scar depth of the alloy steel part in the present disclosure, the existing material No. 1 and the existing material No. 2 at different fatigue friction times. First, comparing the alloy steel part with the existing material No. 1, under the conditions of 60 minutes of fatigue friction time, 90 minutes of fatigue friction time and 120 minutes of fatigue friction time, the weight loss value and wear scar depth value of the alloy steel part in the present disclosure are smaller than those of the existing material No. 1. Similarly, comparing the alloy steel part with the existing material No. 2, under the conditions of 60 minutes of fatigue friction time, 90 minutes of fatigue friction time and 120 minutes of fatigue friction time, the weight loss value and wear scar depth value of the alloy steel part in the present disclosure are smaller than those of the existing material No. 2. It can be seen that the alloy steel part in the present disclosure exhibits good wear resistance.

[0108] Based on the technical solution disclosed in the present invention, an alloy steel part is also provided, which can be formed by any of the above processing techniques. The cavity shape of the target mold can be designed according to the shape of the alloy steel part, and the shrinkage size of the formed blank during the sintering process needs to be considered.

[0109] The present disclosure also provides a folding hinge, which may include the alloy steel parts described in any of the above embodiments. When the folding hinge includes multiple alloy steel parts, the multiple alloy steel parts may be arranged in the same shape or in multiple shapes, and the design is mainly based on the size requirements of the alloy steel parts in the folding hinge. Among them, at least one alloy steel part is used to achieve the hovering of the folding hinge. Since the hovering of the folding hinge can usually achieve infinite hovering by damping, the degree of wear on the related parts is relatively high. Therefore, the alloy steel parts formed by the processing technology in the present disclosure can improve the wear resistance, reduce the amount of wear, and help maintain the movement accuracy of the folding hinge.

[0110] The present disclosure also provides a foldable electronic device, which may include the foldable hinge described in any one of the above embodiments. The foldable electronic device may be a dual-screen foldable device, such as a foldable mobile phone.

[0111] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the disclosure disclosed herein. The present disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are to be considered exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0112] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A processing technology for alloy steel parts, characterized in that: include: Mixing alloy powder and a binder to obtain feed particles, wherein the alloy powder comprises carbon, chromium, nickel, molybdenum, manganese, silicon, vanadium, cobalt and iron; The feed particles are subjected to an injection molding process to obtain a green body; Performing a process of removing the binder from the green body to obtain a formed body; The formed blank is subjected to a heat treatment process to obtain the alloy steel part.

2. The processing technology according to claim 1, characterized in that: The mixing of the alloy powder and the binder to obtain feed particles comprises: obtaining alloy powder and binder respectively; Selecting spherical or nearly spherical alloy powder and the binder according to a target mass ratio, adding them into a mixer for mixing; The mixed metal powder and binder are output from the mixer in multiple stages to obtain the feed particles.

3. The processing technology according to claim 2, characterized in that: The obtaining of alloy powder comprises: Obtaining single substance powders corresponding to each chemical element contained in the alloy powder; The alloy powder is obtained by mixing the single substance powders corresponding to the chemical elements according to the weight percentage of the chemical elements in the alloy powder.

4. The processing technology according to claim 2, characterized in that: The mixing temperature of the alloy powder and the binder in the mixer is greater than or equal to 180° C. and less than or equal to 220° C., and the mixing time is greater than or equal to 2.5 h and less than or equal to 3.5 h.

5. The processing technology according to claim 2, characterized in that: The target mass ratio of the alloy powder to the binder is in the range of 8.5:1-9:

1.

6. The processing technology according to claim 2, characterized in that: The weight percentages of the chemical elements in the alloy powder are as follows: The weight percentage of carbon element is greater than or equal to 1.35% and less than or equal to 1.56%; The weight percentage of chromium is greater than or equal to 5.5% and less than or equal to 7.5%; The weight percentage of nickel element is greater than or equal to 0.36% and less than or equal to 0.7%; The weight percentage of molybdenum element is greater than or equal to 0.6% and less than or equal to 1.05%; The weight percentage of manganese is greater than or equal to 0.25% and less than or equal to 0.44%; The weight percentage of silicon is greater than or equal to 0.15% and less than or equal to 0.62%; The weight percentage of vanadium is less than or equal to 0.1%; The weight percentage of cobalt element is less than or equal to 0.1%; The rest is iron and impurity elements that cannot be completely eliminated.

7. The processing technology according to claim 2, characterized in that: The particle size of the alloy powder is greater than or equal to 10 microns and less than or equal to 30 microns.

8. The processing technology according to claim 1, characterized in that: The binder comprises a paraffin matrix, stearic acid and at least two of the following chemical substances: Polystyrene, polypropylene, high-density polyethylene and low-density polyethylene.

9. The processing technology according to claim 8, characterized in that: The mass percentage of stearic acid in the binder is greater than or equal to 1% and less than or equal to 5%.

10. The processing technology according to claim 1, characterized in that: The step of subjecting the feed particles to an injection molding process to obtain a green body comprises: Adding the feed particles into an injection machine; Injecting the feed particles into a target mold for molding at an injection temperature within a range of 95° C. to 115° C. and an injection pressure within a range of 110 MPa to 130 MPa; The target mold is separated to obtain the green body.

11. The processing technology according to claim 1, characterized in that: The process of removing the binder from the green body to obtain a formed body comprises: The green body is put into a degreasing furnace for degreasing to obtain a brown body; The brown blank is added into a sintering machine for sintering and solidification to obtain the molded blank.

12. The processing technology according to claim 11, characterized in that: The step of adding the green body into a degreasing furnace for degreasing to obtain a brown body comprises: The degreasing temperature in the degreasing furnace is controlled within the range of 105°C-112°C, and nitric acid at a flow rate of 30g / h-45g / h and nitrogen at a flow rate of 400L / h-450L / h are introduced simultaneously to perform degreasing under the conditions of the degreasing furnace to obtain the brown blank.

13. The processing technology according to claim 11, characterized in that: The brown blank is added into a sintering machine for sintering and solidification to obtain the molded blank, comprising: Under the condition that the sintering temperature is controlled within the range of 1235° C.-1250° C., the sintering time is 180 min-200 min to obtain the molded blank.

14. The processing technology according to claim 1, characterized in that: The step of subjecting the formed blank to a heat treatment process to obtain the alloy steel part comprises: Performing quenching treatment on the formed blank; The formed blank after quenching is subjected to tempering treatment to obtain the alloy steel part.

15. The processing technology according to claim 14, characterized in that: The temperature of the quenching treatment is in the range of 510° C.-570° C., and the holding time of the tempering treatment is in the range of 11 h-13 h.

16. An alloy steel part, characterized in that: The method is formed by using a processing technology as described in any one of claims 1 to 15.

17. A folding hinge, characterized in that: Comprising at least one alloy steel part as claimed in claim 16, when the folding hinge comprises a plurality of the alloy steel parts, the plurality of alloy steel parts are arranged in the same shape or in a plurality of shapes.

18. The folding hinge according to claim 17, characterized in that: At least the alloy steel part is used to achieve the suspension of the folding hinge.

19. A foldable electronic device, characterized in that: Comprising a folding hinge as claimed in claim 17 or 18.

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