Processing technology of aluminum alloy workpiece

Abstract

The invention relates to a processing technology of an aluminum alloy workpiece, which comprises the following steps: acquiring a blank: preheating: heating the blank in an environment of 520-600 DEG C for 400-460 minutes, and heating an upper die and a lower die to 400 DEG C or above; primary forging, wherein lubricating oil is smeared on the upper die and the lower die at the same time; the heated blank is placed in a lower die and centered, the blank is stamped to a first position at a first speed through first stamping force of an upper die, and a first-stage aluminum alloy workpiece is obtained; finish forging is conducted, specifically, lubricating oil is evenly smeared on the upper die and the lower die at the same time, the second stamping force of the upper die stamps the blank to the second position at the second speed, and a second-stage aluminum alloy workpiece is obtained; and the connected skin at the bottom of the secondary aluminum alloy workpiece is cut off, and the target aluminum alloy workpiece is obtained. According to the technical scheme, the technical problems that a traditional aluminum alloy workpiece is poor in grain size and quality stability, the number of finished products obtained in a single batch is small, and the production efficiency is low are effectively solved.

Description

Technical Field

[0001] The present application relates to the technical field of metal processing, and in particular to a processing technology for an aluminum alloy workpiece. Background Art

[0002] Aluminum alloy is the most widely used type of non-ferrous metal structural material in industry. Due to its low density, high plasticity, good corrosion resistance, light weight and high strength, it is widely used in aerospace, automobile, machinery manufacturing, shipbuilding and chemical industries.

[0003] In the related art, aluminum alloy workpieces are generally obtained by traditional free forging. However, the grain size of aluminum alloy parts obtained by free forging is poor, the product quality is unstable, and the number of aluminum alloy parts processed in a single batch is small, and the production efficiency is low. Summary of the invention

[0004] The present application provides a processing technology for aluminum alloy workpieces to solve the technical problems of poor grain size and poor quality stability of traditional aluminum alloy workpieces, small number of finished products obtained in a single batch, and low production efficiency.

[0005] To this end, the present application provides a processing technology for an aluminum alloy workpiece, including:

[0006] Obtaining the blank: the mass fractions of the components in the blank are: silicon is 0.06% to 0.76%, iron is 0.3% to 0.6%, copper is 0.28% to 0.4%, manganese is 0.02% to 0.08%, chromium is 0.02% to 0.09%, titanium is 0.03% to 0.08%, bismuth is 0 to 0.003%, lead is 0 to 0.003%, and the rest is aluminum;

[0007] Preheating treatment: Heat the blank at 520℃~600℃ for 400min~460min, and at the same time, heat the upper mold and the lower mold to 400℃ or above;

[0008] Initial forging: clean the debris in the lower die, and apply lubricating oil to the upper and lower dies at the same time; place the heated blank in the lower die and align it, move the upper die to the top of the lower die, and use the first punching force of the upper die to punch the blank to the first position at the first speed, unload the force, and withdraw from the upper die to obtain a first-grade aluminum alloy workpiece;

[0009] Final forging: Lubricating oil is evenly applied to the upper die and the lower die at the same time, the upper die is moved above the lower die, and the second punching force of the upper die is used to punch the blank to the second position at the second speed, and the force is released, and the upper die is withdrawn to obtain a secondary aluminum alloy workpiece;

[0010] The skin at the bottom of the secondary aluminum alloy workpiece is cut off to obtain the target aluminum alloy workpiece.

[0011] In a possible implementation manner, the first speed is 2 mm / s to 4 mm / s; and / or,

[0012] The second speed is 8 mm / s to 10 mm / s.

[0013] In a possible implementation manner, the first position is a distance from the top surface of the blank pressed by the upper mold to the top surface of the blank being recessed by 10 mm to 12 mm; and / or,

[0014] The second position is where the upper mold presses the top surface of the blank to a distance of 10 mm to 12 mm between the top surface of the blank and the bottom surface of the blank.

[0015] In a possible implementation manner, the first punching force is 4500T to 5500T; and / or,

[0016] The second punching force is 7500T~8500T.

[0017] In a possible implementation, the upper die includes a punch rod and a punch, the punch is connected to the movable crossbeam of the press through the punch rod, the lower die includes a lower die connecting seat and a forming cylinder, the forming cylinder is connected to the lower die support of the press through the lower die connecting seat, and the forming cylinder is arranged toward the punch, and the specific steps of the initial forging include:

[0018] Clean the debris in the forming cylinder and apply lubricating oil on the inner wall of the forming cylinder and the pressure head;

[0019] Place the heated blank into the forming cylinder and align it;

[0020] Move the movable crossbeam until the punch is located above the forming tube, and ensure that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°;

[0021] The first punching force of the punch is used to punch the blank to a first position at a first speed, and the force is released and the punch is withdrawn to obtain a first-grade aluminum alloy workpiece.

[0022] In a possible embodiment, the molding cylinder includes a cylinder portion and a gasket, the cylinder portion includes a draft zone and a molding zone that are connected, the draft zone is located above the molding zone, and the radial dimension of the draft zone is larger than the radial dimension of the molding zone, and the gasket is arranged in the molding zone and located on the side of the molding zone away from the draft zone.

[0023] In a possible implementation, the press further includes a first drive assembly, which is disposed on the lower die support and is used to eject the gasket in a first direction.

[0024] In a possible embodiment, the press also includes a workbench and a second drive assembly, and the lower mold support is movably arranged on the workbench through the second drive assembly. The second drive assembly drives the lower mold support to reciprocate along a second direction, and the plane where the second direction is located is perpendicular to the plane where the first direction is located.

[0025] In a possible implementation manner, the specific steps of final forging include:

[0026] At the same time, evenly apply lubricating oil on the inner wall of the forming cylinder and the pressure head;

[0027] Move the movable crossbeam until the punch is located above the forming tube, and ensure that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°;

[0028] The second punching force of the punch is used to punch the blank to a second position at a second speed, and the force is released and the punch is withdrawn to obtain a secondary aluminum alloy workpiece.

[0029] In a possible implementation manner, the specific steps of removing the skin at the bottom of the secondary aluminum alloy workpiece to obtain the target aluminum alloy workpiece include:

[0030] The secondary aluminum alloy workpiece is brought out from the forming cylinder by the punch;

[0031] Continue to move the lower mold support forward until the upper mold completely clears the lower mold;

[0032] The secondary aluminum alloy workpiece is placed on the cut hole washer, and the connection between the movable crossbeam and the punching rod is released; at the same time, the movable crossbeam acts on the punching rod with a third punching force to cut off the skin at the bottom of the secondary aluminum alloy workpiece;

[0033] Take out the punching rod to obtain the desired aluminum alloy workpiece.

[0034] According to the processing technology of the aluminum alloy workpiece provided in the embodiment of the present application, it includes: obtaining a blank: the mass fraction of each component in the blank is: silicon is 0.06% to 0.76%, iron is 0.3% to 0.6%, copper is 0.28% to 0.4%, manganese is 0.02% to 0.08%, chromium is 0.02% to 0.09%, titanium is 0.03% to 0.08%, bismuth is 0 to 0.003%, lead is 0 to 0.003%, and the rest is aluminum; preheating treatment: heating the blank at 520°C to 600°C for 400min to 460min, and at the same time, heating the upper mold and the lower mold to 400°C and above Upper; initial forging: clean the debris in the lower die, and apply lubricating oil on the upper die and the lower die at the same time; put the heated blank in the lower die and align it, move the upper die to the top of the lower die, and make the first punching force of the upper die punch the blank to the first position at a first speed, unload the force, exit the upper die, and obtain a first-level aluminum alloy workpiece; final forging: evenly apply lubricating oil on the upper die and the lower die at the same time, move the upper die to the top of the lower die, and make the second punching force of the upper die punch the blank to the second position at a second speed, unload the force, exit the upper die, and obtain a second-level aluminum alloy workpiece; cut off the skin at the bottom of the second-level aluminum alloy workpiece to obtain the target aluminum alloy workpiece. The technical solution of this application improves the grain refinement of the formed aluminum alloy workpiece and the quality stability of the product by optimizing the chemical composition of the blank and the mass fraction of each component; at the same time, the blank and the upper and lower molds are preheated, which can not only make the blank in the forging process be in the optimal deformation temperature of the material for a long time, improve the deformation and forming effect and after forming, but also make the final forging blank temperature greater than or equal to 400°C, and refine the grain size of the secondary aluminum alloy workpiece formed by the final forging; and, through multiple different forging processes, the blank is reversely extruded forged to avoid problems such as local folding, top distortion, and cracks in the formed aluminum alloy workpiece, thereby improving the quality of the aluminum alloy workpiece. In addition, this processing technology can preheat multiple blanks in batches to improve the production efficiency of aluminum alloy workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments that conform to the present application, and are used together with the specification to explain the principles of the present application. In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can also be obtained based on these drawings without paying creative labor. One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute a proportional limitation.

[0036] Figure 1 A processing flow chart of an aluminum alloy workpiece provided in an embodiment of the present application;

[0037] Figure 2 Low-power micrograph of an aluminum alloy workpiece produced by conventional aluminum alloy processing technology;

[0038] Figure 3 Comparison diagram of the cross-section of aluminum alloy workpieces obtained by traditional aluminum alloy processing technology and standard grain size mapping;

[0039] Figure 4 A low-power micrograph of an aluminum alloy workpiece obtained by the processing technology of the aluminum alloy workpiece provided in the present application;

[0040] Figure 5 A high-magnification grain size index grade test result diagram of an aluminum alloy workpiece obtained by the processing technology of the aluminum alloy workpiece provided by the present application;

[0041] Figure 6 A high-power micrograph of an aluminum alloy workpiece obtained by the processing technology of the aluminum alloy workpiece provided in the present application;

[0042] Figure 7 It is a three-dimensional rendering of an aluminum alloy workpiece obtained by the aluminum alloy workpiece processing technology provided in the present application. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0044] The disclosure below provides many different embodiments or examples to realize the different structures of the present application. In order to simplify the disclosure of the present application, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present application. In addition, the present application can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed in itself. In addition, the various specific processes and examples of materials provided by the present application, but those of ordinary skill in the art can appreciate the applicability of other processes and / or the use of other materials.

[0045] For ease of description, spatial relative terms may be used herein to describe the relative positional relationship or movement of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", "front", "back", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure undergoes a position flip or a posture change or a motion state change, then these directional indications also change accordingly, for example: an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative descriptors used herein are interpreted accordingly.

[0046] See also Figure 1 The present application embodiment provides a processing technology for an aluminum alloy workpiece, comprising:

[0047] Step S1, obtaining a blank: the mass fractions of the components in the blank are: silicon is 0.06% to 0.76%, iron is 0.3% to 0.6%, copper is 0.28% to 0.4%, manganese is 0.02% to 0.08%, chromium is 0.02% to 0.09%, titanium is 0.03% to 0.08%, bismuth is 0 to 0.003%, lead is 0 to 0.003%, and the rest is aluminum;

[0048] Step S2, preheating treatment: heating the blank at 520°C to 600°C for 400min to 460min, and at the same time, heating the upper mold and the lower mold to 400°C or above;

[0049] Step S3, initial forging: clean the debris in the lower die, and apply lubricating oil to the upper die and the lower die at the same time; place the heated blank in the lower die and align it, move the upper die to above the lower die, and use the first punching force of the upper die to punch the blank to the first position at a first speed, unload the force, and withdraw from the upper die to obtain a first-grade aluminum alloy workpiece;

[0050] Step S4, final forging: lubricating oil is evenly applied to the upper die and the lower die at the same time, the upper die is moved to above the lower die, and the second punching force of the upper die is used to punch the blank to the second position at a second speed, and the force is unloaded and the upper die is withdrawn to obtain a secondary aluminum alloy workpiece;

[0051] Step S5, cutting off the skin at the bottom of the secondary aluminum alloy workpiece to obtain the target aluminum alloy workpiece.

[0052] In this embodiment, the chemical composition of the blank and the mass fraction of each component are optimized to improve the grain refinement of the formed aluminum alloy workpiece and improve the quality stability of the product; at the same time, the blank and the upper and lower molds are preheated, which can not only make the blank in the forging process be in the optimal deformation temperature of the material for a long time, improve the deformation and forming effect and after forming, but also make the final forging blank temperature greater than or equal to 400°C, and refine the grain size of the secondary aluminum alloy workpiece formed by the final forging; and, through multiple different forging processes, the blank is reversely extruded forged to avoid problems such as local folding, top distortion, and cracks in the formed aluminum alloy workpiece, thereby improving the quality of the aluminum alloy workpiece. In addition, this processing technology can preheat multiple blanks in batches to improve the production efficiency of aluminum alloy workpieces.

[0053] Specifically, this embodiment selects aluminum billets containing bismuth and lead for processing, and configures the mass fraction of iron in the billet to 0.3% to 0.6%, and the mass fraction of chromium in the billet to 0.02% to 0.09%, so as to refine the grain size in the forged aluminum alloy workpiece and improve the quality stability and reliability of the aluminum alloy workpiece. Then, the billet and the upper and lower molds are preheated at the same time, so that the initial forging temperature of the billet is greater than or equal to 520°C, and the temperature of the upper and lower molds is at least 400°C, so that the billet during the forging process is always at the optimal deformation temperature, which is convenient for billet processing and molding, improves the aesthetics of product molding, and avoids material waste; it can also avoid the problem of excessive grain size in the product due to the rapid drop in billet temperature during the forging process, and refine the grain size in the formed aluminum alloy workpiece. After that, the blank is forged initially. During the initial forging, it is necessary to ensure that there is no debris in the lower die to avoid interfering with the reverse extrusion process of the blank. At the same time, lubricating oil is applied to the upper and lower dies to reduce the adhesion between the upper and lower dies and the blank during the reverse extrusion process, reduce the friction between the blank and the upper and lower dies, and facilitate subsequent extrusion and material removal. After that, the first-level aluminum alloy workpiece is forged. During the final forging, the upper and lower dies need to be lubricated for a second time. During the second lubricating operation, it is necessary to ensure that the lubricating oil applied in the upper and lower dies is evenly distributed to avoid problems such as local folding, top distortion, and cracks in the processed aluminum alloy workpiece, and improve the yield rate of the aluminum alloy workpiece. Finally, the skin at the bottom of the secondary aluminum alloy workpiece can be punched out by punching the washer. The processing technology of the entire aluminum alloy workpiece is simple to operate and highly controllable, which is conducive to industrial-scale production.

[0054] In one example, the lubricating oil includes cylinder oil, engine oil and graphite powder, and the mass fractions of the above components are: cylinder oil is 70% to 80%, engine oil is 20% to 25%, and graphite powder is 5% to 10%. It should be explained that the lubricating oil under this ratio is suitable for lubrication and forging of the blank provided in this application.

[0055] In a possible implementation, the first speed is 2mm / s to 4mm / s; and / or, the second speed is 8mm / s to 10mm / s. Such an arrangement can avoid the problem of too small stamping deformation caused by too small stamping speed of the upper die on the blank during initial forging, and can also avoid the problem of too large blank deformation and too large grain size of the formed blank caused by too large stamping speed of the upper die on the blank during initial forging, so that the stamping and compacting speed of the initial forging is within a suitable range, ensuring the stamping deformation while not affecting the grain size of the subsequent formed aluminum alloy workpiece.

[0056] At the same time, it can avoid the problem that the compaction speed of the upper die on the blank during final forging is too low, resulting in poor stamping forming effect, and it can also avoid the problem that the compaction speed of the upper die on the blank during final forging is too high, resulting in excessive overflow of the blank and substandard quality of the formed aluminum alloy workpiece. The final forging stamping compaction speed is within an appropriate range, ensuring the forming deformation while refining the grain size in the formed aluminum alloy workpiece, thereby improving the stability and reliability of the aluminum alloy workpiece.

[0057] In a possible implementation, the first position is the distance from the top surface of the upper die pressing against the blank to the top surface of the blank being recessed by 10mm to 12mm; and / or, the second position is the distance from the top surface of the upper die pressing against the blank to the distance from the top surface of the blank to the bottom surface of the blank being 10mm to 12mm. Such an arrangement can cause the blank with a higher temperature to produce a smaller deformation during the initial forging and stamping process, thereby avoiding excessive deformation and causing excessive internal grain size of the primary aluminum alloy workpiece, thereby affecting the stability of the primary aluminum alloy workpiece. At the same time, the blank with a lower temperature is subjected to a larger deformation during the final forging process, so that the deformed blank fills the cavity of the lower die and the closed area formed by the compacting punch of the upper die, thereby avoiding the blank overflowing from the cavity of the lower die and causing a waste of raw materials, thereby improving the yield rate of the aluminum alloy workpiece and reducing the production cost of the aluminum alloy workpiece. In addition, the upper mold at the second position does not abut the bottom of the lower mold, which can prevent the upper mold from directly hitting the bottom of the lower mold, improve the mechanical protection of the upper and lower molds, and extend the service life of the upper and lower molds; it can also prevent the blank from overflowing from the top of the lower mold and causing waste of raw materials, and can also avoid the need to cut the material overflowing from the top, shorten the processing process of the aluminum alloy workpiece, reduce the processing time, and improve the processing efficiency.

[0058] Generally speaking, in this embodiment, it is necessary to ensure that the temperature of the billet during initial forging is greater than or equal to 520°C, and the temperature of the billet during final forging is greater than or equal to 400°C.

[0059] In a possible implementation, the first punching force is 4500T to 5500T; and / or, the second punching force is 7500T to 8500T. Such an arrangement can provide a smaller pressure to the blank during the initial forging process, avoid the problem of excessive grain size in the primary aluminum alloy workpiece caused by the large deformation of the blank during the initial forging process, and improve the yield rate of the aluminum alloy workpiece. At the same time, a larger pressure can be provided to the blank during the final forging process, so that it can be deformed to a greater extent and fill the mold cavity, realize the reverse extrusion molding of the aluminum alloy workpiece, and improve the external aesthetics of the formed aluminum alloy workpiece.

[0060] In a possible implementation, the upper die includes a punch rod and a punch, the punch is connected to the movable crossbeam of the press through the punch rod, the lower die includes a lower die connecting seat and a forming cylinder, the forming cylinder is connected to the lower die support of the press through the lower die connecting seat, and the forming cylinder is arranged toward the punch, and the specific steps of the initial forging include:

[0061] Step S31, cleaning the debris in the forming cylinder, and applying lubricating oil on the inner wall of the forming cylinder and the pressure head;

[0062] Step S32, placing the heated blank in the forming cylinder and aligning it;

[0063] Step S33, moving the movable crossbeam until the punch is located above the forming tube, and ensuring that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°;

[0064] Step S34, use the first punching force of the punch to punch the blank to a first position at a first speed, unload the force, withdraw the punch, and obtain a first-level aluminum alloy workpiece.

[0065] In this embodiment, the upper mold is configured as a combined component including at least a punch rod and a punch, wherein the punch rod is used to provide a vertical space, and the punch is used to abut and punch the blank; at the same time, the lower mold is configured as a combined component including at least a lower mold connecting seat and a forming cylinder, wherein the lower mold connecting seat is used to be connected to the lower mold support of the press and can move with the lower mold support, and the forming cylinder is used to accommodate the blank and cooperate with the punch to realize the stamping forming of the blank. Specifically, first remove the debris in the forming cylinder to prevent it from interfering with the blank forming; then, place the heated blank in the forming cylinder, and align the blank to ensure that the blank is located in the center of the forming cylinder, so as to avoid uneven wall thickness of the aluminum alloy workpiece due to uneven force during the subsequent reverse extrusion of the blank, thereby improving the yield rate of the finished aluminum alloy workpiece; then, move the movable crossbeam of the press vertically to align the punch connected to the bottom of the movable crossbeam with the forming cylinder, and ensure that the deviation angle of the axes of the two is less than 1°, and align the punch with the forming cylinder. In this way, when the stamping force is applied in the later stage, the reverse extrusion pressure can be ensured. The punch acts accurately on the center position of the blank to improve the uniformity of the force on the blank and the uniformity of the internal grain size of the blank along its axial direction; finally, the first punching pressure of 4500T to 5500T on the punch is controlled to punch the blank at a first speed of 2mm / s to 4mm / s to a first position where the upper die presses the top surface of the blank to a distance of 10mm to 12mm from the top surface of the blank, and the blank is forged. Then, the punching pressure on the punch is removed and the punch is withdrawn. Under the compaction of the first punching pressure, a step of 10mm to 12mm deep is formed on the top of the blank, and the stamping of the blank is completed to obtain a first-class aluminum alloy workpiece.

[0066] For example but not limited to, the punch is controlled to punch the blank at a first pressure of 5000 tons and a first speed of 3mm / s until the blank is pressed to a depth of 10mm to achieve stamping forging of the blank, and then the pressure on the punch is released, the punch is moved upward to withdraw from the forming cylinder, and a first-grade aluminum alloy workpiece can be obtained.

[0067] In a possible embodiment, the molding cylinder includes a cylinder portion and a gasket, the cylinder portion includes a draft zone and a molding zone that are connected, the draft zone is located above the molding zone, and the radial dimension of the draft zone is larger than the radial dimension of the molding zone, and the gasket is arranged in the molding zone and located on the side of the molding zone away from the draft zone.

[0068] In this embodiment, the forming cylinder is configured as a combined component including at least a cylinder and a gasket. The cylinder can be a cylindrical structure with openings at both ends, which can be arranged vertically. The draft area of ​​the cylinder is located above the forming area, and the draft area has a draft angle of at least 0.1° to solve the problem of difficult demoulding after the blank is formed in the forming cylinder, and to facilitate the removal of the finished aluminum alloy workpiece; and the setting of the draft angle can effectively reduce the problem of scratches and rubbings on the surface of the finished aluminum alloy workpiece when the finished aluminum alloy workpiece is taken out, which affects the appearance, and improves the aesthetics and yield rate of the finished aluminum alloy workpiece. The gasket can be a metal circle, and its external dimensions are adapted to the internal hole area dimensions of the forming area, so that the gasket can be assembled to the bottom of the forming area. In this way, the gasket can be enclosed with the inner hole, punch, etc. of the forming cylinder to form a closed forming cavity to realize the shaping of the blank; and it can also limit the blank from overflowing from the bottom of the forming cylinder to cause material waste, thereby improving the effective utilization rate of the blank. In addition, the movable gasket is also convenient for later material removal, preventing the finished aluminum alloy workpiece from sticking to the gasket, the connection between the gasket and the forming area, etc. For example, when removing the material, the gasket can be removed first, so that both ends of the forming cylinder are open, and then the finished aluminum alloy workpiece can be taken out from the forming cylinder.

[0069] In a possible implementation, the press further includes a first drive assembly, which is disposed on the lower die support and is used to eject the gasket in a first direction.

[0070] In this embodiment, the press is configured as a combined component including at least a lower die support and a first drive assembly, the first drive assembly can be configured in the mounting cavity of the lower die support, the lower die connecting seat is provided with a movable hole connected to the mounting cavity, the first drive assembly can include a first drive member and a push pin, the first drive member can be a lifting hydraulic cylinder, which is configured in the mounting cavity of the lower die support, and the push pin is movably arranged in the movable hole, so that the first drive member and the push pin can be hidden in the lower die support and the lower die connecting seat, on the one hand, the mechanical protection of the first drive member and the push pin is improved to prevent the external environment from causing mechanical damage such as scratches and friction to them, on the other hand, the occupied space of each component is reasonably planned to improve the compactness of the layout of the aluminum alloy production system. The output end of the first drive member is connected to the bottom of the push pin located above it, and the push pin can be driven to reciprocate in the vertical direction. At the same time, the washer is arranged above the push pin, so that the push pin can be driven to move upward by the first drive member to lift the washer, thereby lifting the finished aluminum alloy workpiece located above the washer, which is convenient for demoulding.

[0071] It should be explained that the first direction involved in this embodiment is the vertical direction, that is, the first drive assembly can reciprocate in the vertical direction to eject the gasket when moving upward, thereby lifting up the finished aluminum alloy workpiece located above the gasket to achieve the removal of the finished aluminum alloy workpiece; or, the first drive assembly can move downward to be accommodated in the lower mold support to avoid interfering with the lower mold.

[0072] In addition, the first driving member and the ejector pin can provide upward support force / impact resistance force to the blank through the gasket when the punch extrudes the blank in the forming cylinder. In this way, the upper and lower parts of the blank can be extruded at the same time by applying force on both sides, thereby improving the forming efficiency and forming effect.

[0073] In one example, the first driving member may include a cylinder body, a cylinder cover covering the cylinder body, and a piston rod movably disposed in the cylinder body and passing through the cylinder cover, wherein the movable end of the piston rod abuts against the bottom of the ejector pin, so that the piston rod can be driven to move up and down to drive the ejector pin to move up and down in the movable hole.

[0074] In a possible embodiment, the press also includes a workbench and a second drive assembly, and the lower mold support is movably arranged on the workbench through the second drive assembly. The second drive assembly drives the lower mold support to reciprocate along a second direction, and the plane where the second direction is located is perpendicular to the plane where the first direction is located.

[0075] In this embodiment, the press is configured as a combined component including at least a lower die support, a first drive assembly, a workbench and a second drive assembly. The workbench can be set on a metal platform on the ground, on which a slide rail is set, and the lower die support is slidably connected to the workbench through the slide rail. The second drive assembly can be set in the space below the workbench, which can be a hydraulic drive structure, and the output end is connected to the lower die support, which is used to drive the lower die support to reciprocate along the slide rail.

[0076] It should be explained that the second direction involved in this embodiment is a horizontal direction, that is, the second driving component can reciprocate in the horizontal direction to drive the lower mold to move below the upper mold.

[0077] In a possible implementation manner, the specific steps of final forging include:

[0078] Step S41, simultaneously applying lubricating oil evenly on the inner wall of the forming cylinder and the pressure head;

[0079] Step S42, moving the movable crossbeam until the punch is located above the forming tube, and ensuring that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°;

[0080] Step S43, using the second punching force of the punch to punch the blank to a second position at a second speed, unloading the force, withdrawing the punch, and obtaining a secondary aluminum alloy workpiece.

[0081] In this embodiment, since the lubricating oil applied during the initial forging has been burned or evaporated, when the blank in the forming cylinder is subjected to secondary forging or final forging, the lubricating oil must be evenly applied to the inner wall of the forming cylinder and the abutting surface of the pressure head again to avoid problems such as local folding and top distortion of the finished aluminum alloy workpiece, thereby improving the yield rate of the finished aluminum alloy workpiece; then, the movable crossbeam of the press is moved vertically to align the punch connected to the bottom of the movable crossbeam with the forming cylinder, and ensure that the deviation angle of the axes of the two is less than 1°, and align the punch with the forming cylinder. In this way, when the stamping force is applied in the later stage, it can be ensured that the reverse extrusion pressure acts accurately on the center of the blank. The blank is forged by the punch and the second punching pressure of 7500T to 8500T is controlled to press the blank at a second speed of 8mm / s to 10mm / s until the top surface of the blank is pressed against the top surface of the blank by the upper die and the distance between the top surface of the blank and the bottom surface of the blank is 10mm to 12mm. Then, the punching pressure on the punch is removed and the punch is withdrawn. Under the compaction of the second punching pressure, a 10mm to 12mm thick skin is formed at the bottom of the blank, thus completing the basic shaping of the blank and obtaining a secondary aluminum alloy workpiece.

[0082] For example, but not limited to, controlling the second punching pressure of 8000T on the punch to punch the blank at a second speed of 8mm / s to the second position where the upper die presses the top surface of the blank to a distance of 10mm between the top surface of the blank and the bottom surface of the blank, forging the blank, and then removing the punching pressure on the punch, moving the punch upward so that the punch exits the forming cylinder, and the blank is compacted by the second punching pressure to form a 10mm to 12mm thick skin at its bottom, completing the basic shaping of the blank to obtain a secondary aluminum alloy workpiece.

[0083] In a possible implementation manner, the specific steps of removing the skin at the bottom of the secondary aluminum alloy workpiece to obtain the target aluminum alloy workpiece include:

[0084] Step S51, taking out the secondary aluminum alloy workpiece from the forming cylinder by a punch;

[0085] Step S52, continue to move the lower mold support forward until the upper mold completely avoids the lower mold;

[0086] Step S53, placing the secondary aluminum alloy workpiece on the hole-cutting washer, and releasing the connection between the movable crossbeam and the punching rod; at the same time, causing the movable crossbeam to act on the punching rod with a third punching force to cut off the skin at the bottom of the secondary aluminum alloy workpiece;

[0087] Step S54: Take out the punching rod to obtain the target aluminum alloy workpiece.

[0088] In this embodiment, the upper die is used to directly punch out the skin at the bottom of the secondary aluminum alloy workpiece, which reduces the configuration of the skin cutting device and reduces the cost of use. Specifically, the friction between the punch and the secondary aluminum alloy workpiece is first used to bring the secondary aluminum alloy workpiece out of the forming cylinder. At this time, the secondary aluminum alloy workpiece moves upward with the movable crossbeam until the lower end of the secondary aluminum alloy workpiece is brought to 100mm above the top of the forming cylinder; then, the lower die support is moved away from under the upper die using the slide rail, and the flat anvil behind the lower die support is located below the secondary aluminum alloy workpiece; then, the center of the secondary aluminum alloy workpiece and the hole cutting washer are aligned, and the secondary aluminum alloy workpiece is slowly placed into the tapered end of the inner hole of the hole cutting washer, and the pin between the movable crossbeam and the punching rod is removed. At this time, the punching rod follows the secondary aluminum The alloy workpiece is placed above the cutting gasket; at the same time, the movable crossbeam is driven to act on the top of the punching rod with a third punching force of 5000T, and the punching rod and the punch are used as a skin cutting device to cut off the skin at the bottom of the secondary aluminum alloy workpiece, and then the movable crossbeam is moved upward until it is completely separated from the upper end surface of the punching rod by 50mm; then, the lower die support is continued to move forward until the punching rod and the aluminum alloy workpiece sleeved on the punching rod are moved to the forklift operating area, the aluminum alloy workpiece sleeved on the punching rod is clamped out by driving the forklift's clamp, and the finished aluminum alloy workpiece is transferred to a ventilated position for ventilation and cooling by a forklift to obtain the target aluminum alloy workpiece.

[0089] In order to further illustrate the performance of the aluminum alloy workpiece produced by the processing technology of the aluminum alloy workpiece provided by the present disclosure, the following is described in conjunction with a specific embodiment group. It should be understood that the specific embodiment group is a further detailed description of the present disclosure and does not limit the protection scope of the present disclosure. At the same time, the raw materials and equipment used in the embodiment group can be purchased on the market.

[0090] 1. Selection of the components of the blank and the mass percentage of each component

[0091] 1) Experimental procedures:

[0092] ① Control group: The previous blank components and the mass fractions of each component are selected as follows: 0.70% silicon, 0.29% iron, 0.32% copper, 0.04% manganese, 0.23% chromium, 0.05% zinc, 0.04% titanium, 0.003% lead, 0.001% bismuth, and the rest is aluminum. Then, the blank is heated at 470°C for 400 minutes, and the upper and lower molds are heated to 400°C or above; then, the debris in the lower mold is cleaned, and lubricating oil is applied to the upper and lower molds at the same time; the heated blank is placed in the lower mold and centered, the upper mold is moved above the lower mold, and the upper mold is punched with 5000T punching force for multiple times to obtain an aluminum alloy workpiece with a continuous skin at the bottom; finally, the continuous skin is cut off by a skin cutting device to obtain a finished aluminum alloy workpiece.

[0093] The finished aluminum alloy workpieces were sampled and observed under a low power microscope to obtain the following Figure 2 The finished aluminum alloy workpiece is cut and sampled, and compared with the standard grain size drawing, the following is obtained: Figure 3 The comparison result is shown in the figure.

[0094] ② Experimental group: The selected billet components and the mass fraction of each component are: silicon 0.06%~0.76%, iron 0.3%~0.6%, copper 0.28%~0.4%, manganese 0.02%~0.08%, chromium 0.02%~0.09%, titanium 0.03%~0.08%, bismuth 0~0.003%, lead 0~0.003%, and the rest is aluminum. Then, the blank is heated at 520°C for 400min, and at the same time, the upper die and the lower die are heated to 400°C; then, the debris in the lower die is cleaned, and lubricating oil is applied to the punch of the upper die and the inner wall of the forming tube of the lower die at the same time; the heated blank is placed in the lower die and centered, the upper die is moved above the lower die, and the punch on the upper die is used to punch the blank with a punching force of 5000T and a speed of 4mm / s until a 10mm deep boss is formed on the top of the blank, the first forging is stopped, the pressure on the punch is released, and the punch is moved out of the forming tube to obtain a first-class aluminum alloy workpiece; then, the inner wall of the forming tube and the bottom of the punch are simultaneously pressed. Apply lubricating oil evenly on the end, move the punch to the top of the forming cylinder, and make the punch punch the blank with a punching force of 8000T and a speed of 8mm / s until the top of the blank and its bottom are 10mm apart, stop the final forging, release the pressure on the punch, and move the punch out of the forming cylinder; at this time, since the length of the punch extending into the blank is too large, under the action of the friction between the outer wall of the punch and the blank, the formed blank will move out of the forming cylinder together with the punch, so that the formed blank is taken out; finally, the cutting gasket and the movable crossbeam of the press, the punching rod and the pressure head are used to cooperate with each other to cut off the skin at the bottom of the secondary aluminum alloy workpiece to obtain the target aluminum alloy workpiece.

[0095] The finished aluminum alloy workpieces were sampled and observed under a low power microscope to obtain the following Figure 4 The aluminum alloy workpiece is shown in the low-power microscope micrograph; the finished aluminum alloy workpiece is sampled, and after anodic coating, it is observed under a high-power microscope, and the following is obtained: Figure 5 The finished aluminum alloy workpiece is sampled, ground, polished and etched according to the method of GB / T3246.1, and then observed under a 200x high magnification microscope to obtain the following Figure 6 The partial micrograph shown; and Figure 7 The finished aluminum alloy workpiece renderings.

[0096] 2) Result analysis:

[0097] like Figure 2and Figure 3 As shown, it can be seen that the grain size of the aluminum alloy workpiece produced by the traditional method is unstable, with half of the grains being very fine and the other half being very coarse, which does not meet standard production.

[0098] like Figure 4 As shown, the macrostructure of the aluminum alloy workpiece provided by this application has no shrinkage tail, cracks, pores, foreign inclusions, etc., no stratification, and no coarse grain ring. According to the GB / T3246.2-2012 macrostructure grain size rating chart, the macrostructure grain size meets the second level and above, meeting the production standards. Figure 5 As shown, the high-magnification microstructure of the aluminum alloy workpiece provided by the present application has fine grain structure, and the grain structure is approximately equiaxed. According to GB / T3246.1, the average grain size measured by the intercept method is about 53.8 μm, and the grain grade index G is 5.2. Figure 6 As shown, the microstructure of the aluminum alloy workpiece provided by the present application has no burning characteristics, no coarse compound aggregation, no bright grain segregation, no oxide film, and no coarse grain structure; and the forging deformation of the aluminum alloy workpiece is sufficient, the grain boundary is fine and evenly distributed, the compound is finely broken and evenly distributed, and the grain level index G of the aluminum alloy workpiece is 3.2, which meets the production standards. It can be seen that the internal grain size of the aluminum alloy workpiece prepared by the processing technology of the aluminum alloy workpiece of the present application is refined and uniform, meeting the production standards.

[0099] 2. Performance test of aluminum alloy workpiece

[0100] 1) Experimental operation: Two groups of samples were taken from the aluminum alloy workpieces prepared by the processing technology of the aluminum alloy workpiece provided by the present application to conduct a tensile property test of the material, and the data result diagram shown in Table 1 was obtained;

[0101] Table 1 Performance test results of aluminum alloy workpieces provided in this application

[0102]

[0103] 2) Result analysis: The tensile properties of the aluminum alloy workpiece provided in this application meet the production standards.

[0104] In summary, the aluminum alloy workpiece produced by the processing technology of the aluminum alloy workpiece provided in the present application has good mechanical strength, fine and uniform grain size, and meets the production standards.

[0105] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0106] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0107] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A processing technology for an aluminum alloy workpiece, characterized in that: include: Obtaining a blank: the mass fractions of the components in the blank are: silicon is 0.06% to 0.76%, iron is 0.3% to 0.6%, copper is 0.28% to 0.4%, manganese is 0.02% to 0.08%, chromium is 0.02% to 0.09%, titanium is 0.03% to 0.08%, bismuth is 0 to 0.003%, lead is 0 to 0.003%, and the rest is aluminum; Preheating treatment: heating the blank at 520°C to 600°C for 400min to 460min, and at the same time, heating the upper mold and the lower mold to 400°C or above; Initial forging: clean the debris in the lower die, and apply lubricating oil to the upper die and the lower die at the same time; place the heated blank in the lower die and align it, move the upper die to above the lower die, and use the first punching force of the upper die to punch the blank to the first position at a first speed, unload the force, and withdraw from the upper die to obtain a first-grade aluminum alloy workpiece; Final forging: Lubricating oil is evenly applied to the upper die and the lower die at the same time, the upper die is moved to above the lower die, and the second punching force of the upper die is used to punch the blank to a second position at a second speed, and the force is unloaded and the upper die is withdrawn to obtain a secondary aluminum alloy workpiece; The skin at the bottom of the secondary aluminum alloy workpiece is cut off to obtain the target aluminum alloy workpiece.

2. The processing technology of the aluminum alloy workpiece according to claim 1, characterized in that: The first speed is 2 mm / s to 4 mm / s; and / or, The second speed is 8 mm / s to 10 mm / s.

3. The processing technology of the aluminum alloy workpiece according to claim 1, characterized in that: The first position is a distance from the top surface of the blank pressed by the upper mold to the top surface of the blank being recessed by 10 mm to 12 mm; and / or, The second position is where the upper mold presses against the top surface of the blank to a distance of 10 mm to 12 mm between the top surface of the blank and the bottom surface of the blank.

4. The processing technology of the aluminum alloy workpiece according to claim 1, characterized in that: The first punching force is 4500T to 5500T; and / or, The second punching force is 7500T to 8500T.

5. The processing technology of the aluminum alloy workpiece according to claim 1, characterized in that: The upper die includes a punch rod and a punch, the punch is connected to the movable crossbeam of the press through the punch rod, the lower die includes a lower die connecting seat and a forming cylinder, the forming cylinder is connected to the lower die support of the press through the lower die connecting seat, and the forming cylinder is arranged toward the punch, and the specific steps of the initial forging include: Cleaning the debris in the forming cylinder and applying lubricating oil to the inner wall of the forming cylinder and the pressure head; Placing the heated blank into the forming cylinder and aligning it; Move the movable crossbeam until the punch is located above the forming tube, and ensure that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°; The first punching force of the punch is used to punch the blank to a first position at a first speed, and the force is released and the punch is withdrawn to obtain a first-level aluminum alloy workpiece.

6. The processing technology of the aluminum alloy workpiece according to claim 5, characterized in that: The molding cylinder includes a cylinder portion and a gasket, the cylinder portion includes a draft zone and a molding zone that are connected, the draft zone is located above the molding zone, and the radial dimension of the draft zone is greater than the radial dimension of the molding zone, and the gasket is arranged in the molding zone and located on a side of the molding zone away from the draft zone.

7. The processing technology of the aluminum alloy workpiece according to claim 6, characterized in that: The press also includes a first driving assembly, which is disposed on the lower die support and is used to eject the gasket in a first direction.

8. The processing technology of the aluminum alloy workpiece according to claim 7, characterized in that: The press also includes a workbench and a second driving assembly, the lower die support is movably arranged on the workbench through the second driving assembly, and the second driving assembly drives the lower die support to reciprocate along a second direction, and the plane where the second direction is located is perpendicular to the plane where the first direction is located.

9. The processing technology of the aluminum alloy workpiece according to claim 5, characterized in that: The specific steps of the final forging include: At the same time, lubricating oil is evenly applied on the inner wall of the forming cylinder and the pressure head; Move the movable crossbeam until the punch is located above the forming tube, and ensure that the angle deviation between the axis of the punch and the axis of the forming tube is less than 1°; The second punching force of the punch is used to punch the blank to a second position at a second speed, and the force is released and the punch is withdrawn to obtain a secondary aluminum alloy workpiece.

10. The processing technology of the aluminum alloy workpiece according to claim 9, characterized in that: The specific steps of removing the skin at the bottom of the secondary aluminum alloy workpiece to obtain the target aluminum alloy workpiece include: Taking out the secondary aluminum alloy workpiece from the forming cylinder by the punch; Continue to move the lower mold support forward until the upper mold completely avoids the lower mold; The secondary aluminum alloy workpiece is placed on the hole cutting washer, and the connection between the movable crossbeam and the punching rod is released; at the same time, the movable crossbeam acts on the punching rod with a third punching force to cut off the skin at the bottom of the secondary aluminum alloy workpiece; The punching rod is taken out to obtain the target aluminum alloy workpiece.

Images