Metal part and processing technology thereof

Abstract

The present invention provides a metal part and a processing technology thereof, relating to the technical field of titanium alloy frame processing. The metal part comprises a titanium alloy frame and an aluminum alloy internal component. The titanium alloy frame is provided with a plurality of grooves on its inner side for pouring molten aluminum alloy; the molten aluminum alloy contains a flow aid. The present invention provides a groove structure on the inner side of the titanium alloy frame. These grooves allow the molten aluminum alloy to be poured into the grooves and, after cooling, form a tight mechanical interlocking structure with the titanium alloy frame. This structure significantly improves the adhesion between the two materials and better balances the stress generated by differences in thermal expansion coefficients.

Description

Technical Field

[0001] The present invention relates to the technical field of titanium alloy frame processing, in particular to a metal part and a processing technology thereof. Background Art

[0002] With the rapid advancement of global technology, smartphones with titanium alloy frames are a breath of fresh air, leading the way in the current smartphone market. This innovative design not only showcases the perfect fusion of technology and aesthetics, but also demonstrates a profound understanding of materials science and manufacturing processes. Simultaneously, titanium, a material that shares the lightweight and high-strength characteristics of titanium alloys, is also emerging as a revolutionary material choice for mobile phones. While titanium and titanium alloys share similarities in basic composition and certain physical properties, titanium alloys, through sophisticated alloying processes, often exhibit superior hardness, superior corrosion resistance, and improved overall mechanical properties. These exceptional performance advantages pave the way for the widespread adoption of titanium alloys in future smartphones. Not only is it a preferred material for mobile phone frames, providing both strong and lightweight support, it can also be cleverly incorporated into other key components of mobile phones, such as delicate buttons and elegant bezels, enhancing overall durability while also lending the product a unique aesthetic appeal.

[0003] On the other hand, the importance of aluminum alloy, a traditional material for mobile phone internal components, cannot be ignored. Due to its many advantages, including low density, high strength, excellent processability, and cost-effectiveness, aluminum alloy has long been an ideal material for mobile phone internal support structures, precision cooling systems, and other key components. The widespread use of aluminum alloy not only effectively reduces the overall weight of mobile phones, allowing users to enjoy a lighter and more portable experience, but also ensures that mobile phones maintain sufficient structural strength and stability while maintaining a thin and light design, providing a solid guarantee for the durability and reliability of mobile phones.

[0004] However, it's worth noting that titanium alloys and aluminum alloys exhibit significant differences in a key physical property, namely their coefficient of thermal expansion. The coefficient of thermal expansion is a key physical property that measures the degree to which a material changes in size when exposed to temperature. This difference in property presents a significant challenge for mobile phone design and manufacturing. When a phone is exposed to different temperatures, the titanium alloy frame and aluminum alloy internal components will expand or contract to varying degrees due to their differing coefficients of thermal expansion. This dimensional difference can compromise the bond between the two and, in extreme cases, even lead to tiny gaps or looseness. These issues not only pose a potential threat to the overall structural stability of the phone but also negatively impact its waterproof and dustproof performance. These seemingly insignificant gaps can potentially become "backdoors" for moisture and dust intrusion, impacting the phone's proper functionality and lifespan. Therefore, effectively addressing the challenges posed by the difference in coefficients of thermal expansion between titanium and aluminum alloys during design and manufacturing has become a critical and pressing issue. Summary of the Invention

[0005] In order to solve the above-mentioned problems, the present invention aims to provide a metal part and its processing technology. The present invention sets a groove structure on the inner side of the titanium alloy frame. These grooves allow aluminum alloy liquid to be poured into them, and after cooling, form a tight mechanical locking structure with the titanium alloy frame. This structure can significantly improve the adhesion between the two materials and can also better balance the stress caused by the difference in thermal expansion coefficients.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a metal part, which includes a titanium alloy frame and an aluminum alloy internal component;

[0008] A plurality of grooves are provided on the inner side of the titanium alloy frame, and the grooves are used for pouring aluminum alloy liquid;

[0009] Wherein, the aluminum alloy liquid contains a flow aid.

[0010] Further, based on the above technical solution, the groove includes at least one of a dovetail groove or a T-slot;

[0011] And / or, the edge of the groove is a smooth curve.

[0012] Furthermore, based on the above technical solution, the size of the notch connecting the groove and the inner side of the titanium alloy frame is 100-500 μm;

[0013] The size ratio of the groove bottom to the groove mouth is (2.5-3.5):1.

[0014] Further, based on the above technical solution, the flow aid includes one or more of silane, silicone, vapor deposited silicon, aluminum chloride, sodium silicate or magnesium oxide;

[0015] The amount of the flow aid added is 0.001-0.01% of the total mass of the aluminum alloy liquid;

[0016] The temperature of the aluminum alloy liquid is 740-780°C.

[0017] Furthermore, based on the above technical solution, the groove is formed by 3D printing.

[0018] Furthermore, based on the above technical solution, a plurality of bosses are further provided on the inner side of the titanium alloy frame;

[0019] The boss includes at least one of a dovetail boss and a T-shaped boss.

[0020] Further, on the basis of the above technical solution, the titanium alloy includes one of Ti-6Al-4V titanium alloy, Ti-8Al-1Mo-1V titanium alloy, TC4 titanium alloy or TA18 titanium alloy;

[0021] And / or, the aluminum alloy includes one of 6013 aluminum alloy, 7R03 aluminum alloy, 6061 aluminum alloy, 6063 aluminum alloy, 7005 aluminum alloy, 7075 aluminum alloy or 2117 aluminum alloy.

[0022] The present invention also provides a processing technology for the above-mentioned metal part, comprising the following steps:

[0023] S1: 3D printing is used to prepare the titanium alloy frame and the grooves and bosses inside the titanium alloy frame;

[0024] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid, and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0025] S3: The rough metal parts are polished, anodized and subjected to aging heat treatment to obtain finished metal parts.

[0026] Furthermore, on the basis of the above technical solution, in step S3, the anodic oxidation is to place the polished metal part in an electrolytic cell, the electrolyte in the electrolytic cell includes a mixture of 0.5-2 mol / L sulfuric acid solution, 0.5-1.0 mol / L oleic acid hydroxyethyl imidazoline and 0.5-1.0 mol / L sodium sulfate, with a titanium alloy frame as the anode and graphite as the cathode, DC electrolysis for 20-40 s, and the current density is controlled at 0.10-0.30 A / cm 2 , the bath temperature is controlled at 30-50°C, and after completion, it is rinsed with deionized water and dried;

[0027] And / or, in step S3, the polishing treatment includes chemical treatment and / or mechanical treatment.

[0028] Furthermore, based on the above technical solution, in step S3, the aging heat treatment includes: hot pressing and curing the anodized metal part at a curing temperature of 800-950° C. for 30-60 minutes, and cooling;

[0029] Then heat to 500-600℃, keep it for 6-10h, and obtain the finished metal part after cooling.

[0030] The present invention provides a metal part and a processing technology thereof, which has the following beneficial effects:

[0031] 1. The present invention provides a groove structure on the inner side of the titanium alloy frame. These grooves allow aluminum alloy liquid to be poured into them and form a tight mechanical locking structure with the titanium alloy frame after cooling. This structure can significantly improve the adhesion between the two materials.

[0032] 2. In the present invention, the addition of a flow aid to the aluminum alloy liquid can significantly reduce the surface tension of the aluminum alloy liquid, thereby greatly improving its flow properties, so that the aluminum alloy liquid can flow more smoothly into the designed smaller groove during the pouring process. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 This is a schematic diagram of the groove structure inside the titanium alloy frame provided by the present invention;

[0035] icon:

[0036] 1. Titanium alloy frame; 2. Dovetail groove; 21. Dovetail groove opening; 22. Dovetail groove bottom; 3. T-slot; 31. T-slot opening; 32. T-slot bottom; 4. Dovetail boss; 5. T-boss. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. The process parameters for which specific conditions are not specified in the following examples are generally in accordance with conventional conditions.

[0038] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to form one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed in the present invention.

[0039] According to a first aspect of the present invention, there is provided a metal part, comprising a titanium alloy frame 1 and an aluminum alloy internal component;

[0040] The inner side of the titanium alloy frame 1 is provided with a plurality of grooves, and the grooves are used for pouring aluminum alloy liquid;

[0041] Wherein, the aluminum alloy liquid contains a flow aid.

[0042] Specifically, due to the significant difference in thermal expansion coefficients between titanium alloys and aluminum alloys, this difference can cause significant stress between the two materials when the temperature changes, thereby affecting the adhesion between them. To avoid the poor adhesion caused by this stress, the present invention cleverly provides grooves on the inner side of the titanium alloy frame. The original design of these grooves is to allow the aluminum alloy liquid to be poured into them, and after cooling, it forms a tight mechanical locking structure with the titanium alloy frame, which can significantly improve the adhesion between the two materials.

[0043] As an optional embodiment of the present invention, the groove includes at least one of a dovetail groove 2 or a T-slot 3 .

[0044] Specifically, the design of the groove shape can significantly affect the thermal expansion and stress distribution between the titanium alloy frame and the aluminum alloy liquid. For example, patent CN105525336B provides a carbon fiber metal composite electronic product body structure, which includes an aluminum alloy frame and a carbon fiber middle frame plate located inside the aluminum alloy frame and integrally composited with the aluminum alloy frame. The aluminum alloy frame has a microporous structure formed by surface corrosion treatment. The carbon fiber middle frame plate is combined with the surface of the aluminum alloy frame having the microporous structure and is formed into a single piece through hot pressing and curing.

[0045] However, the micropores formed by chemical corrosion treatment in this patent cannot be effectively controlled, and may form micropores of various shapes and sizes. When faced with stress caused by differences in thermal expansion coefficients, these micropores cannot effectively manage and control stress, causing the frame structure to deform, crack or produce gaps, thereby affecting the overall airtightness and structural integrity.

[0046] The present application sets a dovetail groove or T-slot structure in the titanium alloy frame, or cleverly combines the two to form a hybrid structure, which shows excellent mechanical properties when facing the stress challenge caused by the difference in shrinkage between aluminum and titanium. Figure 1 As shown, these groove structures can effectively resist shrinkage forces in the Y direction, ensuring the stability of the structure in this direction; in the X direction, the dovetail groove and T-slot structure, with its unique mortise and tenon design, achieve a firm connection in the X direction, effectively preventing shrinkage and displacement of the aluminum alloy. In addition, the T-slot structure, with its stable support, provides additional resistance in the Y direction, further enhancing the overall stability of the structure. When the two are used in combination, they can play a synergistic role, allowing the structure to maintain its integrity and airtightness under bidirectional tension. This innovative structural design not only solves the problems caused by the difference in shrinkage rates when combining aluminum and titanium, but also improves the airtightness and stability of the structure, providing strong support for technological progress and application expansion in related fields.

[0047] As an optional embodiment of the present invention, the edge of the groove is a smooth curve.

[0048] Specifically, when the aluminum alloy liquid is poured into the groove, stress concentration is often inevitable, especially at the sharp corners of the dovetail groove with complex structure or the T-slot with extremely high stability requirements. This stress concentration will pose a severe challenge to the subsequent tight connection between the titanium alloy frame and the aluminum alloy structure. Specifically, it may cause a significant decrease in the airtightness between the two, causing tiny gaps to appear in the interface that should have been tightly fitted, thereby affecting the sealing performance and protection level of the overall structure. At the same time, stress concentration may also weaken the stability of the connection part, increase the risk of deformation of the structure under long-term stress conditions, and may even cause connection failure, seriously affecting the service life and safety performance of the product. Therefore, in order to avoid the adverse effects of this stress concentration on the airtightness and stability between the titanium alloy frame and the aluminum alloy structure, the present invention optimizes the design of the groove shape, and makes the edge of the groove a smooth curve by increasing the transition radius to effectively disperse and relieve stress concentration, thereby ensuring the reliability and durability of the final product.

[0049] As an optional embodiment of the present invention, the groove is connected to the notch on the inner side of the titanium alloy frame (such as Figure 1The dovetail notch 21 and T-slot notch 31 shown are 100-500 μm in size;

[0050] The bottom of the groove in the titanium alloy frame (such as Figure 1 The size ratio of the dovetail groove bottom 22 and the T-slot bottom 32 to the groove opening is (2.5-3.5):1.

[0051] Specifically, this application limits the size ratio of the groove bottom to the groove mouth to (2.5-3.5):1 because, when the aluminum alloy liquid is poured into the groove, the groove designed within this ratio range can better disperse the stress generated by the thermal expansion coefficient of aluminum and titanium.

[0052] As an optional embodiment of the present invention, the flow aid includes one or more of silane, silicone, vapor-deposited silicon, aluminum chloride, sodium silicate or magnesium oxide, preferably aluminum chloride.

[0053] Specifically, when faced with the relatively small groove structures specifically designed in the present invention, the inherent surface tension of the molten aluminum alloy causes considerable resistance when pouring into these delicate grooves, making the pouring process extremely difficult. This resistance not only prevents the molten aluminum alloy from evenly and fully penetrating every corner of the groove, but also significantly increases the risk of incomplete filling of the entire groove structure, thereby affecting the quality and performance of the final product. Therefore, the present invention adds a small amount of flow aid to the molten aluminum alloy to improve its fluidity, making it smoother and easier to flow. This improvement allows the molten aluminum alloy to better conform to the complex shape of the groove structure during pouring, achieving more uniform filling even in the most subtle and hard-to-reach areas. Furthermore, the addition of the flow aid effectively reduces the surface tension of the molten aluminum alloy during pouring, further weakening the physical barrier that originally prevented the molten aluminum alloy from completely filling the groove.

[0054] As an optional embodiment of the present invention, the added amount of the flow aid is 0.001-0.01% (such as 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, etc.) of the total mass of the aluminum alloy liquid.

[0055] Specifically, as an effective additive, flow aid can significantly reduce the surface tension of aluminum alloy liquid, thereby greatly improving its flow properties, allowing the aluminum alloy liquid to flow more smoothly during the infusion process. However, although flow aid brings many benefits, controlling its addition amount is a key link that requires careful control.

[0056] Specifically, the amount of flow aid added must be strictly controlled within a reasonable range. This is because an appropriate amount of flow aid can effectively promote the fluidity of the aluminum alloy liquid, reduce the formation of bubbles, improve filling efficiency, and ultimately improve the surface quality and overall performance of the aluminum alloy internal components. However, if it is added in excess, it may have an adverse effect on the crystal growth of the aluminum alloy internal components, causing changes in the crystal structure, and thus affecting key properties such as the mechanical properties of the aluminum alloy internal components. In addition, excessive flow aids may also cause other process problems, such as increasing the viscosity of the aluminum alloy liquid, affecting its cooling rate, and may even cause defects inside the casting.

[0057] On the contrary, if the amount of flow aid added is too small, its effect on improving the fluidity of the aluminum alloy liquid will become less obvious and it will not be able to fully play its due role. It will also lead to unstable quality of the internal components of the aluminum alloy and difficulty in meeting the design requirements.

[0058] As an optional embodiment of the present invention, the temperature of the aluminum alloy liquid is 740-780°C (such as 745°C, 750°C, 755°C, 760°C, 765°C, 770°C, 775°C, etc.).

[0059] Specifically, the conventional casting temperature of aluminum alloys is usually set in the range of 630°C to 700°C. This range ensures that the molten alloy has good fluidity and appropriate solidification characteristics, thus meeting the requirements of most casting processes. However, when faced with the relatively small groove structure specially designed in the present invention, conventional casting temperatures seem to be somewhat inadequate. In order to ensure that these fine grooves can be fully and evenly filled with the aluminum alloy liquid and achieve the ideal molding effect, it is necessary to make adjustments based on the conventional casting temperature. Specifically, the casting temperature is increased by 10°C to 50°C. The temperature of the aluminum alloy liquid is closely related to its fluidity: the higher the temperature, the more intense the molecular activity inside the alloy, which gives it better fluidity. Good fluidity means that the aluminum alloy liquid can flow more smoothly and fill every corner of the mold, including those small and complex groove parts. This not only significantly improves the molding quality of the casting and reduces defects caused by poor filling, such as pores and shrinkage, but also ensures that the final product has higher dimensional accuracy and surface finish. However, if the casting temperature is too high, the amount of air absorbed by the molten aluminum increases, causing pinholes, shrinkage cavities, and surface blistering in the thick walls of the casting. This also accelerates mold corrosion, leading to premature aging and cracking. If the casting temperature is too low, the fluidity is poor, and defects such as cold shuts, flow lines, and insufficient pouring are likely to occur. If the temperature is too low, the molten aluminum is prone to composition deviations, resulting in hard spots in the casting and affecting mechanical properties.

[0060] As an optional embodiment of the present invention, the groove is formed by 3D printing.

[0061] As an optional embodiment of the present invention, a plurality of bosses are further provided on the inner side of the titanium alloy frame;

[0062] The boss includes a dovetail boss or a T-shaped boss.

[0063] Specifically, if Figure 1 As shown, a plurality of dovetail bosses or T-shaped bosses are provided on the inner side of the titanium alloy frame. The dovetail boss 4 or T-shaped boss 5 is the same size as the dovetail groove 2 or T-shaped groove 3. The purpose of this arrangement is to balance the thermal expansion and stress distribution between the titanium alloy and the aluminum alloy, and to further strengthen the mechanical locking connection force between the titanium alloy frame and the aluminum alloy internal components and improve the bonding strength.

[0064] As an optional embodiment of the present invention, the titanium alloy includes one of Ti-6Al-4V titanium alloy, Ti-8Al-1Mo-1V titanium alloy, TC4 titanium alloy or TA18 titanium alloy.

[0065] As an optional embodiment of the present invention, the aluminum alloy includes one of 6013 aluminum alloy, 7R03 aluminum alloy, 6061 aluminum alloy, 6063 aluminum alloy, 7005 aluminum alloy, 7075 aluminum alloy or 2117 aluminum alloy.

[0066] Specifically, groove or boss structures often have complex geometric shapes, and 3D printing technology manufactures objects by stacking materials layer by layer, so it can easily realize the manufacture of such complex shapes. 3D printing technology is an additive manufacturing process that only uses the required materials to manufacture objects, thereby reducing the generation of scrap and the waste of materials. For groove or boss structures, this feature is particularly significant because it can precisely control the amount of material according to actual needs. In addition, 3D printing technology also helps to achieve green manufacturing and sustainable development. Through 3D printing technology, multiple components that require multi-step processing and assembly in traditional manufacturing can be designed into an integrated structure. For groove or boss structures, this means that multiple micropores and connecting parts can be integrated into a whole, thereby improving the overall performance and reliability of the product.

[0067] According to a second aspect of the present invention, there is provided a process for processing the above-mentioned metal part, comprising the following steps:

[0068] S1: 3D printing is used to prepare the titanium alloy frame and the grooves and bosses inside the titanium alloy frame;

[0069] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid, and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0070] S3: The rough metal parts are polished, anodized and subjected to aging heat treatment to obtain finished metal parts.

[0071] As an optional embodiment of the present invention, in step S3, the polishing treatment includes chemical treatment and / or mechanical treatment.

[0072] Specifically, chemical treatment includes pickling, for example: using 30% hydrochloric acid or concentrated nitric acid to clean the crude metal parts;

[0073] Specifically, the purpose of pickling is to remove organic matter, grease, dust and other impurities on the surface of the rough metal parts, thereby providing a clean surface for subsequent anodizing.

[0074] The mechanical treatment includes surface grinding and cleaning.

[0075] Specifically, the surface grinding includes: using a grinding tool to lightly grind the rough metal product to increase the surface area, which is conducive to the anodic oxidation of the rough metal product in the electrolyte;

[0076] The cleaning process includes: cleaning the surface with alcohol to remove impurities and residues generated during the polishing process.

[0077] As an optional embodiment of the present invention, in step S3, the anodic oxidation is to place the polished metal part in an electrolytic cell, wherein the electrolyte in the electrolytic cell includes a 0.5-2 mol / L sulfuric acid solution, 0.5-1.0 mol / L oleic acid hydroxyethyl imidazoline and 0.5-1.0 mol / L sodium sulfate mixture, with a titanium alloy frame as the anode and graphite as the cathode, and DC electrolysis for 20-40 s, and the current density is controlled at 0.10-0.30 A / cm 2 The bath temperature is controlled at 30-50°C, preferably 40°C. After completion, rinse with deionized water and dry.

[0078] As an optional embodiment of the present invention, in step S3, the aging heat treatment includes: hot pressing and curing the anodized metal part at a curing temperature of 800-950° C. for 30-60 minutes, and cooling;

[0079] Then heat to 500-600℃, keep it for 6-10h, and obtain the finished metal part after cooling.

[0080] The present invention will be further described in detail below with reference to specific examples and comparative examples.

[0081] Example 1

[0082] The titanium alloy used in this embodiment is Ti-6Al-4V, and the aluminum alloy is 7005.

[0083] S1: Use 3D printing to prepare titanium alloy frame, set up multiple Figure 1 The dovetail slots, T-slots, dovetail bosses, and T-bosses shown;

[0084] Among them, the groove opening of the dovetail groove and the T-slot are both 200μm, and the groove bottom is both 500μm;

[0085] Notch: bottom of groove = 1:2.5;

[0086] The sizes of the dovetail boss and the T-shaped boss are the same as those of the dovetail slot and the T-shaped slot.

[0087] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature of 750°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0088] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.005% of the total mass of the aluminum alloy liquid.

[0089] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0090] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0091] The anodized metal rough product was hot-pressed and cured at a temperature of 850°C for 55 minutes, and then cooled;

[0092] Then heat to 550°C, maintain for 6 hours, and cool to obtain the finished metal part.

[0093] Example 2

[0094] The titanium alloy used in this embodiment is TC4 and the aluminum alloy is 6013.

[0095] S1: A titanium alloy frame is prepared by 3D printing and multiple dovetail grooves and dovetail bosses are set;

[0096] Among them, the dovetail groove has a notch of 300 μm and a bottom of 900 μm;

[0097] Notch: bottom of groove = 1:3;

[0098] The size of the dovetail boss is the same as that of the dovetail groove.

[0099] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature 770°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0100] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.004% of the total mass of the aluminum alloy liquid;

[0101] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0102] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 1 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 0.8 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 30 seconds with a current density of 0.30 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0103] The anodized metal rough product is hot-pressed and cured at a temperature of 900°C for 50 minutes, and then cooled;

[0104] Then heat to 500°C, maintain for 7 hours, and obtain the finished metal part after cooling.

[0105] Example 3

[0106] The titanium alloy used in this embodiment is Ti-8Al-1Mo-1V, and the aluminum alloy is 6061.

[0107] S1: A titanium alloy frame is prepared by 3D printing and provided with multiple T-slots and T-shaped bosses;

[0108] Among them, the dovetail groove has a notch of 100 μm and a bottom of 350 μm;

[0109] Notch: bottom of groove = 1:3.5;

[0110] The size of the T-shaped boss is the same as that of the T-shaped slot.

[0111] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature 780°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0112] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.008% of the total mass of the aluminum alloy liquid;

[0113] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0114] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.10 A / cm 2 , the bath temperature is controlled at 30 ° C, and after completion, it is rinsed with deionized water and dried;

[0115] The anodized metal rough product is hot-pressed and cured at a temperature of 950°C for 40 minutes, and then cooled;

[0116] Then heat to 600℃, keep it for 6 hours, and obtain the finished metal part after cooling.

[0117] Example 4

[0118] The titanium alloy used in this embodiment is TA18, and the aluminum alloy used is 6063.

[0119] S1: Use 3D printing to prepare titanium alloy frame, set up multiple Figure 1 As shown Figure 1 The dovetail slots, T-slots, dovetail bosses, and T-bosses shown;

[0120] Among them, the groove opening of the dovetail groove and the T-slot are both 200μm, and the groove bottom is both 600μm;

[0121] Notch: bottom of groove = 1:3;

[0122] The sizes of the dovetail boss and the T-shaped boss are the same as those of the dovetail slot and the T-shaped slot.

[0123] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature of 750°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0124] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.005% of the total mass of the aluminum alloy liquid;

[0125] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0126] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 1 mol / L sulfuric acid solution, 0.7 mol / L oleic acid hydroxyethyl imidazoline, and 1.0 mol / L sodium sulfate. The titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 30 s with a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0127] The anodized metal rough product is hot-pressed and cured at a temperature of 850°C for 35 minutes, and then cooled;

[0128] Then heat to 550℃, keep it for 7h, and cool it to obtain the finished metal part.

[0129] Example 5

[0130] The titanium alloy used in this embodiment is Ti-6Al-4V, and the aluminum alloy is 7075.

[0131] S1: A titanium alloy frame is prepared by 3D printing and multiple dovetail grooves and dovetail bosses are set;

[0132] Among them, the dovetail groove has a notch of 500 μm and a bottom of 1250 μm;

[0133] Notch: bottom of groove = 1:2.5;

[0134] The size of the dovetail boss is the same as that of the dovetail groove.

[0135] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature 740°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0136] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.001% of the total mass of the aluminum alloy liquid;

[0137] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0138] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 1 mol / L sulfuric acid solution, 1 mol / L oleic acid hydroxyethyl imidazoline, and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 30 seconds with a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0139] The anodized metal rough product is hot-pressed and cured at a temperature of 850°C for 35 minutes, and then cooled;

[0140] Then heat to 600℃, keep it for 8 hours, and obtain the finished metal part after cooling.

[0141] Comparative Example 1

[0142] The difference between this comparative example and Example 1 is that no grooves and bosses are provided in the titanium alloy frame, specifically:

[0143] The titanium alloy used in this comparative example is Ti-6Al-4V, and the aluminum alloy is 7005.

[0144] S1: Titanium alloy frame prepared by 3D printing;

[0145] S2: Place the titanium alloy frame in a mold and pour aluminum alloy liquid (temperature is 750°C). After the aluminum alloy liquid cools, internal components are formed to obtain a rough metal part.

[0146] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0147] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0148] The anodized metal rough product was hot-pressed and cured at a temperature of 850°C for 55 minutes, and then cooled;

[0149] Then heat to 550°C, maintain for 6 hours, and cool to obtain the finished metal part.

[0150] Comparative Example 2

[0151] The difference between this comparative example and Example 1 is that the poured aluminum alloy liquid does not contain a flow aid, specifically:

[0152] The titanium alloy used in this comparative example is Ti-6Al-4V, and the aluminum alloy is 7005.

[0153] S1: Use 3D printing to prepare titanium alloy frame, set up multiple Figure 1 The dovetail slots, T-slots, dovetail bosses, and T-bosses shown;

[0154] Among them, the groove opening of the dovetail groove and the T-slot are both 200μm, and the groove bottom is both 500μm;

[0155] Notch: bottom of groove = 1:2.5;

[0156] The sizes of the dovetail boss and the T-shaped boss are the same as those of the dovetail slot and the T-shaped slot.

[0157] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature of 750°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0158] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0159] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0160] The anodized metal rough product was hot-pressed and cured at a temperature of 850°C for 55 minutes, and then cooled;

[0161] Then heat to 550°C, maintain for 6 hours, and cool to obtain the finished metal part.

[0162] Comparative Example 3

[0163] The difference between this comparative example and Example 1 is that the temperature of the poured aluminum alloy liquid is 700°C. Specifically:

[0164] The titanium alloy used in this comparative example is Ti-6Al-4V, and the aluminum alloy is 7005.

[0165] S1: Use 3D printing to prepare titanium alloy frame, set up multiple Figure 1 The dovetail slots, T-slots, dovetail bosses, and T-bosses shown;

[0166] Among them, the groove opening of the dovetail groove and the T-slot are both 200μm, and the groove bottom is both 500μm;

[0167] Notch: bottom of groove = 1:2.5;

[0168] The sizes of the dovetail boss and the T-shaped boss are the same as those of the dovetail slot and the T-shaped slot.

[0169] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature of 700°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0170] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.005% of the total mass of the aluminum alloy liquid;

[0171] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0172] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0173] The anodized metal rough product was hot-pressed and cured at a temperature of 850°C for 55 minutes, and then cooled;

[0174] Then heat to 550°C, maintain for 6 hours, and cool to obtain the finished metal part.

[0175] Comparative Example 4

[0176] The difference between this comparative example and Example 1 is that the amount of the flow aid added is 0.015%, specifically:

[0177] The titanium alloy used in this comparative example is Ti-6Al-4V, and the aluminum alloy is 7005.

[0178] S1: Use 3D printing to prepare titanium alloy frame, set up multiple Figure 1 The dovetail slots, T-slots, dovetail bosses, and T-bosses shown;

[0179] Among them, the groove opening of the dovetail groove and the T-slot are both 200μm, and the groove bottom is both 500μm;

[0180] Notch: bottom of groove = 1:2.5;

[0181] The sizes of the dovetail boss and the T-shaped boss are the same as those of the dovetail slot and the T-shaped slot.

[0182] S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid (temperature of 750°C), and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part;

[0183] The flow aid in the aluminum alloy liquid is aluminum chloride, and its addition amount accounts for 0.015% of the total mass of the aluminum alloy liquid;

[0184] S3: The rough metal parts are first pickled (with 30% hydrochloric acid) to remove oxides and contaminants on the metal surface, and then polished in a grinder to obtain a smoother and brighter surface;

[0185] The polished metal parts were placed in an electrolytic cell. The electrolyte in the electrolytic cell included a mixture of 2 mol / L sulfuric acid solution, 1.0 mol / L oleic acid hydroxyethyl imidazoline and 1.0 mol / L sodium sulfate. A titanium alloy frame was used as the anode and graphite was used as the cathode. DC electrolysis was performed for 40 s at a current density of 0.20 A / cm 2 , the bath temperature is controlled at 40 ° C, and after completion, it is rinsed with deionized water and dried;

[0186] The anodized metal rough product was hot-pressed and cured at a temperature of 850°C for 55 minutes, and then cooled;

[0187] Then heat to 550°C, maintain for 6 hours, and cool to obtain the finished metal part.

[0188] Performance testing:

[0189] 90-degree peel test: In a peel tester, one end of the sample is fixed and the other end is peeled off at a 90-degree angle. The maximum peel force during the peeling process is measured.

[0190] Impact test: refer to the hammer test in GB / T 2423.55-2006;

[0191] Shear test: Refer to ASTM B769.

[0192] Table 1 Components and their corresponding mass percentages in Examples 1-4 and Comparative Examples 1-4

[0193]

[0194] As shown in Table 1, compared with Example 1, in Comparative Example 1, since grooves and bosses are not provided in the titanium alloy frame, there is a significant difference in the thermal expansion coefficients of the titanium alloy and the aluminum alloy, which causes significant stress to be generated between the two materials when the temperature changes, thereby affecting the adhesion between them, resulting in a significant decrease in the peel strength and shear strength of the metal parts, and even cracks after the impact test.

[0195] As shown in Table 1, compared with Example 1, Comparative Example 2 has poor fluidity and high surface tension due to the fact that no flow aid is added to the poured aluminum alloy liquid in Comparative Example 2. Therefore, during the pouring process, due to the small size of the notch, the aluminum alloy liquid cannot be fully poured into some grooves, resulting in a decrease in the adhesion between the aluminum alloy and the titanium alloy frame, which affects the mechanical properties of the metal part.

[0196] As shown in Table 1, compared with Example 1, in Comparative Example 3, the temperature of the poured aluminum alloy liquid is lower, which makes the fluidity of the aluminum alloy liquid worse. Therefore, during the pouring process, due to the small size of the notch, the aluminum alloy liquid cannot be fully poured into some grooves, resulting in a decrease in the adhesion between the aluminum alloy and the titanium alloy frame, affecting the mechanical properties of the metal part.

[0197] As shown in Table 1, compared with Example 1, in Comparative Example 4, due to the excessive addition of flow aid in Comparative Example 4, the crystal structure of the aluminum alloy internal component changes, thereby affecting the adhesion between the aluminum alloy internal component and the titanium alloy frame, and further affecting the mechanical properties of the metal parts.

[0198] To sum up, the present invention provides grooves and boss structures on the inner side of the titanium alloy frame. These grooves allow the aluminum alloy liquid to be poured into them, and form a tight mechanical locking structure with the titanium alloy frame after cooling. This structure can significantly improve the adhesion between the two materials, and adding a flow aid to the aluminum alloy liquid can significantly reduce the surface tension of the aluminum alloy liquid, thereby greatly improving its flow properties, so that the aluminum alloy liquid can flow more smoothly into the designed smaller grooves during the pouring process.

[0199] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A metal part, characterized in that: The metal parts include a titanium alloy frame and an aluminum alloy internal component; A plurality of grooves are provided on the inner side of the titanium alloy frame, and the grooves are used for pouring aluminum alloy liquid; Wherein, the aluminum alloy liquid contains a flow aid; The groove includes at least one of a dovetail groove or a T-slot; The edge of the groove is a smooth curve; The flow aid includes one or more of silane, silicone, vapor-deposited silicon, aluminum chloride, sodium silicate or magnesium oxide; The amount of the flow aid added is 0.001-0.01% of the total mass of the aluminum alloy liquid; The temperature of the aluminum alloy liquid is 740-780°C; The inner side of the titanium alloy frame is also provided with a plurality of bosses; The boss includes at least one of a dovetail boss and a T-shaped boss.

2. The metal part according to claim 1, characterized in that The size of the notch connecting the groove and the inner side of the titanium alloy frame is 100-500 μm; The size ratio of the groove bottom to the groove mouth is (2.5-3.5):

1.

3. The metal member according to claim 1, wherein: The groove is formed by 3D printing.

4. The metal member according to claim 1, wherein: The titanium alloy includes one of Ti-6Al-4V titanium alloy, Ti-8Al-1Mo-1V titanium alloy, TC4 titanium alloy or TA18 titanium alloy; And / or, the aluminum alloy includes one of 6013 aluminum alloy, 7R03 aluminum alloy, 6061 aluminum alloy, 6063 aluminum alloy, 7005 aluminum alloy, 7075 aluminum alloy or 2117 aluminum alloy.

5. A process for processing a metal part according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: 3D printing is used to prepare the titanium alloy frame and the grooves and bosses inside the titanium alloy frame; S2: placing the titanium alloy frame in a mold, pouring aluminum alloy liquid, and forming internal components after the aluminum alloy liquid cools to obtain a rough metal part; S3: The rough metal parts are polished, anodized and subjected to aging heat treatment to obtain finished metal parts.

6. The metal parts processing technology according to claim 5, characterized in that: In step S3, the anodic oxidation is to place the polished metal part in an electrolytic cell, wherein the electrolyte in the electrolytic cell includes a mixture of 0.5-2 mol / L sulfuric acid solution, 0.5-1.0 mol / L oleic acid hydroxyethyl imidazoline and 0.5-1.0 mol / L sodium sulfate, with a titanium alloy frame as the anode and graphite as the cathode, and DC electrolysis for 20-40 s, with a current density controlled at 0.10-0.30 A / cm 2 , the bath temperature is controlled at 30-50°C, and after completion, it is rinsed with deionized water and dried; And / or, in step S3, the polishing treatment includes chemical treatment and / or mechanical treatment.

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