Aluminum alloy cargo compartment plate, preparation method thereof, aluminum alloy cargo compartment and truck

Abstract

The application discloses an aluminum alloy truck compartment plate and a preparation method thereof, an aluminum alloy truck compartment and a truck. The aluminum alloy truck compartment plate is used for surrounding formation of a truck compartment. In the up-down direction of the truck compartment, the thickness of the aluminum alloy truck compartment plate is gradually changed. The aluminum alloy truck compartment plate is gradually changed in the up-down direction, so that when the aluminum alloy truck compartment plate is used for surrounding formation of a truck compartment, the thickness of each position of the aluminum alloy truck compartment plate can be correspondingly set according to the stress condition of the truck compartment in actual use. On the premise of not affecting the use performance, the weight of the aluminum truck compartment is reduced as a whole, the lightweight of the aluminum truck compartment is realized, the price gap between the aluminum truck compartment and the iron truck compartment is narrowed, the market share of the aluminum truck compartment can be improved, and the process of replacing steel with aluminum is promoted.

Description

[0001] This invention has priority to the invention patent filed on March 11, 2022, with application number 202210242897.3 and title "Lightweight Variable Cross Section Carriage and Vehicle". Technical Field

[0002] This invention relates to the field of truck technology, and particularly to the field of truck cargo box side panel technology, specifically to an aluminum alloy cargo box panel and its preparation method, an aluminum alloy cargo box, and a truck. Background Technology

[0003] Aluminum alloys possess advantages such as low density, high specific strength, good corrosion resistance, and high recycling value, making them an important material carrier for achieving lightweighting in automobiles. However, the high cost and relatively low hardness of aluminum alloys are hindering the automotive industry's progress in replacing steel with aluminum. Currently, steel cargo boxes have a large market share, while aluminum cargo boxes have a small market share. Further reducing the weight of aluminum cargo boxes without compromising performance, thereby narrowing the price gap between aluminum and steel cargo boxes, is key to increasing the market share of aluminum cargo boxes and promoting the replacement of steel with aluminum. Summary of the Invention

[0004] The main objective of this invention is to provide an aluminum alloy cargo box panel and its preparation method, an aluminum alloy cargo box, and a truck, with the aim of achieving lightweighting of aluminum cargo boxes.

[0005] To achieve the above objectives, the present invention proposes an aluminum alloy cargo box panel, which is used to enclose and form a cargo box, wherein the thickness of the aluminum alloy cargo box panel gradually changes in the vertical direction of the cargo box.

[0006] Optionally, the aluminum alloy cargo box sheet is made from aluminum alloy plates of equal thickness, and is rolled into aluminum alloy plates of varying thickness in one pass using round rollers with varying gaps.

[0007] Optionally, the aluminum alloy cargo box panels are pressed into a corrugated structure.

[0008] Optionally, individual corrugations in the corrugated structure extend in the vertical direction.

[0009] Optionally, the thickness of the aluminum alloy cargo box panels gradually decreases from bottom to top.

[0010] Optionally, the aluminum alloy cargo box panel has at least one transition zone extending in the vertical direction, and the thickness of the aluminum alloy cargo box panel in the transition zone changes continuously.

[0011] Optionally, the transition zone includes a linear transition zone with linearly varying thickness and / or a curved transition zone with non-linearly varying thickness.

[0012] Optionally, the aluminum alloy cargo box plate is further provided with at least one equal thickness zone extending in the vertical direction, the equal thickness zone being adjacent to the transition zone, and the thickness being the same at the connection between the equal thickness zone and the transition zone.

[0013] Optionally, the aluminum alloy cargo box plate is provided with multiple transition zones and multiple equal thickness zones, and the multiple transition zones and multiple equal thickness zones are arranged alternately.

[0014] Optionally, the maximum thickness of the aluminum alloy cargo box sheet is A1, and the minimum thickness of the aluminum alloy truck sheet is A2, where A1 / A2≤3.

[0015] Furthermore, the present invention also proposes an aluminum alloy cargo box, the aluminum alloy cargo box including cargo box side panels, the cargo box side panels including aluminum alloy cargo box plates as described above.

[0016] Optionally, the aluminum alloy cargo box further includes a plurality of uprights extending in the vertical direction, the uprights being fixedly connected to the inner side of the side panel of the aluminum alloy cargo box.

[0017] Optionally, the aluminum alloy cargo box also includes a protective panel, which is detachably mounted on the uprights.

[0018] Furthermore, the present invention also proposes a truck that includes an aluminum alloy cargo box as described above.

[0019] Furthermore, this invention also proposes a method for preparing aluminum alloy cargo box panels, wherein the aluminum alloy cargo box panels are used to enclose and form a cargo box, and the thickness of the aluminum alloy cargo box panels gradually changes in the vertical direction of the cargo box. The method for preparing the aluminum alloy cargo box panels includes the following steps:

[0020] Aluminum alloy plate of equal thickness is selected as raw material, and aluminum alloy plate of equal thickness is rolled into shape in one pass by a circular roller variable gap rolling method to obtain aluminum alloy plate of variable thickness.

[0021] The aluminum alloy variable thickness plate is subjected to annealing, mechanical pretreatment, chemical pretreatment and anodizing in sequence to obtain aluminum alloy cargo box plate with variable thickness.

[0022] Optionally, the aluminum alloy plate of equal thickness is made of 3XXX series aluminum alloy or 5XXX series aluminum alloy.

[0023] Optionally, the aluminum alloy plate of equal thickness is made of AA5754-O state aluminum alloy.

[0024] Optionally, in the step of rolling the aluminum alloy plate of uniform thickness using variable gap rolling:

[0025] The roll gap of the circular roller is B, and the target thickness of the rolling area of ​​the aluminum alloy plate of equal thickness is C, where B = (85-95%) * C.

[0026] Optionally, in the step of forming the aluminum alloy plate of uniform thickness in one pass using a variable gap rolling mill:

[0027] Both sides of the roller are equipped with coiling machines, which simultaneously roll the aluminum alloy plate of equal thickness in reverse.

[0028] Optionally, in the step of rolling the aluminum alloy plate of uniform thickness using variable gap rolling:

[0029] Lubricant is sprayed at the contact point between the roller and the aluminum alloy plate of equal thickness.

[0030] Optionally, the lubricant includes kerosene and vegetable oil, wherein the volume ratio of kerosene to vegetable oil is 1:0 to 1:5.

[0031] Optionally, the step of annealing the aluminum alloy variable thickness plate includes:

[0032] The aluminum alloy thickened plate is placed in a bell-type annealing furnace, heated to 250-450°C within 2 hours, held at that temperature for 2-6 hours, and then the heating is stopped to allow the aluminum alloy thickened plate to cool naturally in the furnace.

[0033] Optionally, after the step of sequentially annealing, mechanical pretreatment, chemical pretreatment, and anodizing the aluminum alloy variable thickness plate to obtain the aluminum alloy cargo box plate with variable thickness, the method further includes:

[0034] The aluminum alloy cargo box sheet is pressed to give it a corrugated structure, wherein each corrugation in the corrugated structure extends in the vertical direction.

[0035] In the technical solution of this invention, by designing the aluminum alloy cargo box panels to be gradually varied in the vertical direction, when the cargo box is formed by enclosing the aluminum alloy cargo box panels, the thickness of the aluminum alloy cargo box side panels at various positions can be set according to the stress conditions of the cargo box during actual use. The side panels are appropriately thickened where the impact pressure of the cargo is greater, thereby improving the puncture and impact resistance of the aluminum alloy cargo box side panels. At the positions where the impact pressure of the cargo is relatively less, the side panels are appropriately thinned while ensuring that the panels have sufficient strength, thereby reducing the overall weight of the aluminum cargo box. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0037] Figure 1 A top view of the plug-in side panels of the aluminum alloy cargo box;

[0038] Figure 2 A schematic cross-sectional view of an embodiment of the aluminum alloy cargo box panel provided by the present invention;

[0039] Figure 3 for Figure 2 Side view;

[0040] Figure 4 A schematic diagram of the structure of the uprights and protective plates in one embodiment of the aluminum alloy cargo box provided by the present invention;

[0041] Figure 5 This is a schematic flowchart of an embodiment of the method for preparing aluminum alloy cargo box panels provided by the present invention;

[0042] Figure 6 This is a schematic flowchart of another embodiment of the method for preparing aluminum alloy cargo box panels provided by the present invention.

[0043] Explanation of icon numbers:

[0044] label name label name 10 Aluminum alloy cargo box panels 105 Third equal-thickness zone 101 First transition zone 12 Corrugated structure 102 Second transition zone 20 Column 103 First equal thickness zone 30 Protective board 104 Second equal-thickness zone

[0045] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0047] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0048] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0049] This invention proposes an aluminum alloy cargo box panel, which is used to enclose and form a cargo box. The aluminum alloy cargo box panel is a single-layer panel. Figures 2 to 3 The illustration shows an embodiment of the aluminum alloy cargo box sheet provided by the present invention. The thickness of the aluminum alloy cargo box sheet 10 gradually changes along the vertical direction of the cargo box (hereinafter, "vertical direction" refers to the vertical direction of the cargo box or truck). That is, the thickness of the aluminum alloy cargo box sheet 10 is not uniform in the vertical direction.

[0050] To reduce the weight of aluminum cargo boxes, prior to the improvements of this invention, a plug-in side panel solution was typically used, such as... Figure 1 As shown, the side panel is composed of several interlocking plate units. These interlocking plate units are manufactured through extrusion molding and consist of inner and outer layers with a reinforcing rib in between. The inner and outer layers are 0.8 mm thick, the reinforcing rib is 1.0 mm thick, and the distance between the inner and outer layers is approximately 25 mm. This hollow extruded profile structure helps improve the rigidity of the side panel, but the double-layered structure also results in a relatively large side panel weight (the total weight of the 4.2m*2.1m*2.1m cargo box side panel is approximately 0 kg). In addition, the thickness of each interlocking plate unit is only 0.8 mm, making it easily punctured and scratched during cargo impact. Furthermore, for stability reasons, cargo is usually located in the lower middle part of the side panel during loading, while the upper part of the side panel bears relatively less impact pressure. Therefore, there is room for structural optimization and weight reduction, but the interlocking side panel design makes it difficult to achieve effective structural optimization and weight reduction.

[0051] In the technical solution of this invention, by designing the aluminum alloy cargo box panels to be gradually varied in the vertical direction, when the cargo box is formed by enclosing the aluminum alloy cargo box panels, the thickness of the aluminum alloy cargo box side panels at various positions can be set according to the stress conditions of the cargo box during actual use. The side panels are appropriately thickened where the impact pressure of the cargo is greater, thereby improving the puncture and impact resistance of the aluminum alloy cargo box side panels. At the positions where the impact pressure of the cargo is relatively less, the side panels are appropriately thinned while ensuring that the panels have sufficient strength, thereby reducing the overall weight of the aluminum cargo box.

[0052] Furthermore, in some embodiments of the present invention, the aluminum alloy cargo box sheet is made from aluminum alloy plates of uniform thickness, and is rolled into aluminum alloy plates of varying thickness in a single pass using variable-gap circular rollers. Thus, by employing a single-pass rolling process with variable-gap circular rollers, both the thickness and performance of the sheet material are controlled. This ensures that even thinner sections of the aluminum alloy cargo box sheet can still meet the required strength, and also avoids problems such as performance degradation at joints and increased production steps associated with laser welding, further guaranteeing the performance of the aluminum alloy cargo box sheet.

[0053] See Figure 3 As shown, in some embodiments of the present invention, the aluminum alloy cargo box panel 10 is further pressed into a corrugated structure 12, which helps to improve the rigidity of the aluminum alloy cargo box panel 10. Specifically, the individual corrugations in the corrugated structure 12 extend in the vertical direction, that is, the orientation of the individual corrugations is consistent with the thickness variation direction of the aluminum alloy cargo box panel 10. The corrugated structure 12 can be formed by a molding machine or a roll forming machine. The corrugated structure 12 can be evenly distributed on the aluminum alloy cargo box panel 10, or it can be only partially provided on the aluminum alloy cargo box panel 10, depending on factors such as actual strength requirements, processing difficulty, and aesthetics.

[0054] There are several ways to set the thickness of the aluminum alloy cargo box plate 10 in a gradually changing manner in the vertical direction. For example, the thickness of the lower part of the aluminum alloy cargo box plate 10 may be greater than the thickness of the upper part, that is, the lower part is thicker and the upper part is thinner; or the thickness of the middle part of the aluminum alloy plate 10 may be greater than the thickness of the upper and lower parts, that is, the middle part is thicker and the two ends are thinner, etc. The specific design can be made according to the stress conditions of the cargo box in actual application, and all of them are within the protection scope of this invention.

[0055] Specifically, in one embodiment of the present invention, the thickness of the aluminum alloy cargo box plate 10 gradually decreases from bottom to top. In actual use of the cargo box, it is more common for the lower part of the side panels to bear more impact from goods and experience greater force, while the upper part of the side panels bears relatively less impact and experiences less force. Therefore, designing the aluminum alloy cargo box plate 10 to be thicker at the bottom and thinner at the top effectively reduces the weight of the aluminum alloy cargo box while ensuring sufficient strength of the aluminum alloy cargo box plate 10.

[0056] There are various ways to achieve a gradual change in the thickness of the aluminum alloy cargo box panel 10, such as a continuous change, a stepped change, or a combination of continuous and stepped changes. In one embodiment of the present invention, the thickness of the aluminum alloy cargo box panel 10 is configured to change continuously. Specifically, the aluminum alloy cargo box panel 10 has at least one transition zone extending in the vertical direction, and the thickness of the aluminum alloy cargo box panel 10 in the transition zone changes continuously. By setting the transition zone, the strength of the aluminum alloy cargo box panel 10 can be better guaranteed, and the manufacturing process of the aluminum alloy cargo box panel 10 can be simplified.

[0057] Furthermore, in a specific embodiment of the present invention, the transition region includes a linear transition region with linearly varying thickness and / or a curved transition region with non-linearly varying thickness. That is, when only one transition region is provided, the transition region can be configured to have a linearly varying thickness or a non-linearly varying thickness; when multiple transition regions are provided, each transition region can be independently configured to have a linearly varying thickness or a non-linearly varying thickness.

[0058] The present invention does not limit the number of transition zones. When there is only one transition zone, the transition zone can extend from the bottom to the top of the aluminum alloy cargo box plate 10, or it can be distributed only on a portion of the aluminum alloy cargo box plate 10. That is, the aluminum alloy cargo box plate 10 can be configured such that its overall thickness changes continuously in the vertical direction, or it can be configured such that its thickness changes in a stepped manner in the vertical direction. Specifically, in Figure 2 In the illustrated embodiment, the transition zone includes a first transition zone 101 and a second transition zone 102 arranged sequentially along the vertical direction. Both the first transition zone 101 and the second transition zone 102 are configured with a linearly varying thickness, which simplifies the manufacturing process of the aluminum alloy cargo box panel 10. More specifically, the height of both the first transition zone 101 and the second transition zone 102 (height in this document refers to the dimension along the vertical direction) is set to 50 mm.

[0059] Furthermore, in this embodiment of the invention, the aluminum alloy cargo box plate 10 is also provided with at least one equal thickness region extending in the vertical direction. The equal thickness region is adjacent to the transition region, and the thickness at the connection between the equal thickness region and the transition region is consistent. In this way, the aluminum alloy cargo box plate 10 is relatively smooth overall, avoiding sudden changes in thickness that would make the aluminum alloy cargo box plate more susceptible to damage from cargo impacts, as well as reducing processing difficulties.

[0060] Similarly, the present invention does not limit the number of equal thickness zones; one or more can be provided. Preferably, in an embodiment of the present invention, the aluminum alloy cargo box plate 10 is provided with multiple transition zones and multiple equal thickness zones, which are arranged alternately. Specifically, in Figure 2 In the illustrated embodiment, the equal thickness region includes a first equal thickness region 103, a second equal thickness region 104, and a third equal thickness region 105 arranged sequentially along the vertical direction. The first equal thickness region 103 and the second equal thickness region 104 are connected by a first transition region 101, and the second equal thickness region 104 and the third equal thickness region 105 are connected by a second transition region 102. More specifically, the height of the first equal thickness region 103 is 1000 mm, the height of the second equal thickness region 104 is 700 mm, and the height of the third equal thickness region 105 is 300 mm. It should be noted that... Figure 2 The dimensions shown are only one embodiment provided by the present invention, and the dimensions marked therein do not represent the actual dimensions. In the actual design and processing of the aluminum alloy cargo box plate 10, the corresponding dimensions should be designed according to the actual needs of the aluminum alloy cargo box.

[0061] Furthermore, in an embodiment of the present invention, the maximum thickness of the aluminum alloy cargo box panel 10 is A1, the minimum thickness of the aluminum alloy cargo box panel 10 is A2, and A1 / A2 ≤ 3. This ensures that the aluminum alloy cargo box panel meets performance requirements while reducing weight. That is, regardless of whether the maximum or minimum thickness of the aluminum alloy cargo box panel 10 is located in the transition zone or the equal thickness zone, it is sufficient that the ratio of the maximum thickness A1 to the minimum thickness A2 does not exceed 3. Specifically, in Figure 2 In the embodiment shown, the aluminum alloy cargo box plate 10 has the maximum thickness at the third equal thickness zone 105, and the aluminum alloy cargo box plate 10 has the minimum thickness at the first equal thickness zone 103. The thicknesses of the first equal thickness zone 103, the second equal thickness zone 104, and the third equal thickness zone 105 are set to 0.8 mm, 1.2 mm, and 1.5 mm, respectively.

[0062] The present invention also proposes an aluminum alloy cargo box, wherein the aluminum alloy cargo box includes a cargo box side panel, and the cargo box side panel includes an aluminum alloy cargo box sheet 10. The specific structure of the aluminum alloy cargo box sheet 10 is as described in the above embodiments. It is understood that since the aluminum alloy cargo box provided by the present invention adopts all the embodiments of the aluminum alloy cargo box sheet 10 provided by the present invention, it has at least all the beneficial effects brought by the above embodiments, which will not be described in detail here.

[0063] When the aluminum alloy cargo box panels 10 are assembled to form the aluminum alloy cargo box, the side panels are thicker at the bottom and thinner at the top. The side panels are connected to each other by welding, riveting, or gluing, and are fixed to the upper and lower longitudinal frames of the cargo box by riveting or welding. Further reference... Figure 4 As shown, the aluminum alloy cargo box also includes multiple vertically extending columns 20, which are fixedly connected to the inner surfaces of the cargo box side panels. Thus, by installing the columns 20 inside the cargo box and connecting the cargo box side panels to the columns 20, the aluminum alloy cargo box panels 10 are further secured, improving structural stability and strength. It should be noted that when the aluminum alloy cargo box panels 10 have the corrugated structure 12, the number of columns 20 can be appropriately reduced. Figure 4 In the illustrated embodiment, the number of columns 20 is 9.

[0064] The uprights 20 can be made of aluminum or non-aluminum profiles, such as solid wood profiles, and are fixed to the upper and lower longitudinal frames of the cargo box by means of nailing, riveting, or bolting. After the aluminum alloy cargo box panels 10 and the uprights 20 are assembled, an overall CAE analysis of the cargo box and a CAE analysis of the side panel stiffness can be performed. Based on the simulation results, the corrugated structure 12 on the aluminum alloy cargo box panels 10 and / or the structural design of the uprights 20 can be adjusted in a timely manner until the CAE simulation analysis is passed.

[0065] Further, see Figure 4As shown, in an embodiment of the present invention, the aluminum alloy cargo box further includes a protective plate 30, which is detachably installed on the upright 20. The protective plate 30 can be made of readily available, lightweight, and low-cost materials, such as wood, including but not limited to poplar wood, and preferably has a thickness of no more than 3mm. Thus, the protective plate 30 protects the cargo box side panels from direct transmission of impact forces from cargo collisions, extending the service life of the cargo box side panels and solving the problems of inconvenient installation and adjustment of the inner protective plate due to the lack of a frame structure in plug-in side panel designs. Furthermore, by detachably connecting the protective plate 30 to the upright 20, such as by nailing, the height of the protective plate 30 can be adjusted vertically according to the actual loading conditions, effectively protecting the cargo box side panels. In this embodiment of the present invention, through the corrugated structure 12, the upright 20, and the protective plate 30, the cargo box side panels can ultimately be 30-50kg lighter than plug-in side panels.

[0066] The cargo box side panel solution provided by this invention is conducive to promoting the development of aluminum alloy variable thickness plate rolling technology. Combined with subsequent stamping, rolling, molding, stretching, bending, welding and other processes, it can produce more aluminum alloy variable thickness plate products for automobiles and accelerate the process of replacing steel with aluminum in automobile parts.

[0067] The present invention also proposes a truck, which includes an aluminum alloy cargo box, the specific structure of which refers to the above embodiments. It is understood that since the truck provided by the present invention adopts all the embodiments of the aluminum alloy cargo box provided above, it possesses at least all the beneficial effects brought about by the above embodiments, which will not be elaborated further here.

[0068] This invention also proposes a method for preparing aluminum alloy cargo box sheet 10. First, the aluminum alloy cargo box sheet 10 is designed structurally and dimensionally according to the structural design concept of the aluminum alloy cargo box sheet 10 provided above. Then, it is formed by single-pass rolling using a variable gap circular roll forming method to obtain the aluminum alloy cargo box sheet 10. See details below. Figure 5 As shown, the method for preparing the aluminum alloy cargo box panel 10 includes the following steps:

[0069] Step S10: Select aluminum alloy equal thickness plate as raw material, and roll the aluminum alloy equal thickness plate in one pass using the variable gap rolling method to obtain aluminum alloy variable thickness plate.

[0070] Step S20: The aluminum alloy variable thickness plate is subjected to annealing, mechanical pretreatment, chemical pretreatment and anodizing in sequence to obtain aluminum alloy cargo box plate 10 with variable thickness.

[0071] Using aluminum alloy plates of uniform thickness as raw material, the plates are rolled using a variable-gap rolling process in a single pass. During rolling, the thickness is varied by adjusting the gap between the rollers (i.e., the distance between the roller surfaces). A thickness gauge is installed at the roller gap exit, and a barcode reader is installed behind the gauge to measure the rolled length of the plate. This variable-gap single-pass rolling method avoids the performance degradation at joints and increased production steps associated with laser welding, further ensuring the performance of the aluminum alloy cargo box plate 10. After rolling, the variable-thickness aluminum alloy plate undergoes annealing. This simple heat treatment process allows for differentiated control of both the thickness and performance of the variable-thickness plate, ensuring strength in the thinner sections. Subsequently, mechanical pretreatment, chemical pretreatment, and anodizing are performed sequentially to improve the surface quality of the variable-thickness aluminum alloy plate.

[0072] In this embodiment of the invention, the aluminum alloy plate of equal thickness is preferably made of 3XXX series aluminum alloy or 5XXX series aluminum alloy, which has the characteristics of good formability and no heat treatment strengthening, which helps to ensure the formability of the plate and reduce the heat treatment process and cost.

[0073] In a specific embodiment of the present invention, the aluminum alloy plate of equal thickness is made of AA5754-O state aluminum alloy.

[0074] When using variable gap rolls to roll the aluminum alloy car body sheet 10, it is preferable to select an aluminum alloy sheet of equal thickness that is slightly thicker than the thickest part of the target sheet as the rolling material. During the rolling process, the roll gap is adjusted in a timely manner to achieve variable thickness rolling. Specifically, the roll gap is B, and the target thickness of the rolling area of ​​the aluminum alloy sheet of equal thickness is C, where B = (85-95%) * C. That is, the roll gap is set to be 5-15% smaller than the target thickness of each part of the sheet to compensate for the thickness deviation caused by elastic deformation of the sheet and roll deflection and flattening deformation, thereby achieving high-precision forming of the sheet.

[0075] In a specific embodiment of the present invention, B = (88-90%) * C.

[0076] Furthermore, in this embodiment of the invention, coilers are provided on both sides of the circular roll, that is, coilers are provided on both the feeding side and the discharge side of the circular roll, simultaneously and in reverse, coiling the aluminum alloy sheet of equal thickness during rolling. In other words, the coilers apply tension to the aluminum alloy sheet during rolling to improve the flatness of the rolled sheet. The coiling force applied by the motor on the discharge side of the roll should not be less than the coiling force applied by the motor on the feeding side of the roll to ensure smooth feeding and rolling.

[0077] Furthermore, during the rolling process, a lubricant is sprayed at the contact point between the roller and the aluminum alloy plate of equal thickness to reduce the thermal crown of the roller and improve the flatness of the plate surface and the uniformity of internal stress distribution. Specifically, the lubricant includes kerosene and vegetable oil, with a volume ratio of kerosene to vegetable oil of 1:0 to 1:5. That is, in some embodiments of the present invention, the lubricant may consist only of kerosene. In other embodiments of the present invention, the lubricant may also include both kerosene and vegetable oil, and the volume ratio of kerosene to vegetable oil is not less than 1:5.

[0078] To facilitate subsequent annealing of the aluminum alloy variable thickness plate, it is preferable to form the rolled aluminum alloy variable thickness plate into coils before annealing. Specifically, in this embodiment of the invention, the step of annealing the aluminum alloy variable thickness plate includes:

[0079] The aluminum alloy variable-thickness plate is placed in a bell-type annealing furnace. The aluminum alloy variable-thickness plate is in coil form, with an inner diameter greater than 100 mm and an outer diameter not greater than the inner diameter of the bell-type annealing furnace. The center of the coil is aligned along a straight line along its height. The aluminum alloy variable-thickness plate is then heated to 250–450 °C within 2 hours and held at this temperature for 2–6 hours. After holding at 250–350 °C for an appropriate time, the rolled area with a deformation exceeding 30% undergoes a high degree of static recrystallization, resulting in significantly refined grains. This leads to a simultaneous increase in the strength and elongation of the rolled plate in this area. In the area with a deformation not exceeding 30%, high-temperature annealing causes static recovery of the grains, significantly reducing the internal defect density. However, the grains retain their post-deformation fibrous structure and exhibit a preferred orientation, resulting in a dual strengthening effect of texture strengthening and fiber-like strengthening in this area. Simultaneously, the static recovery ensures that the rolled plate in this area maintains a moderate elongation. After the heat preservation is completed, heating can be stopped, the furnace door can be opened, and the aluminum alloy thickened plate coil can be allowed to cool down naturally and slowly inside the furnace. This cooling method achieves the stabilization of aluminum alloy properties and can avoid the aging softening phenomenon caused by abnormal segregation and growth of aging precipitates at grain boundaries and other locations at room temperature.

[0080] See Figure 3 As shown, in some other embodiments of the present invention, the aluminum alloy cargo box panel 10 is further designed with a corrugated structure 12, and each corrugation in the corrugated structure 12 extends in the vertical direction, that is, the orientation of each corrugation is consistent with the thickness variation direction of the aluminum alloy cargo box panel 10. Correspondingly, see [reference]. Figure 6 As shown, the method for preparing the aluminum alloy cargo box plate 10, after step S20, further includes the following steps:

[0081] Step S30: Press the aluminum alloy cargo box plate 10 to give it a corrugated structure, wherein each corrugation in the corrugated structure extends in the vertical direction.

[0082] The corrugated structure 12 can be formed by a molding machine or a roll forming machine. The corrugated structure 12 can be evenly distributed on the aluminum alloy cargo box plate 10, or the corrugated structure 12 can be set only in a local part of the aluminum alloy cargo box plate 10. The specific method can be determined by comprehensively considering factors such as actual strength requirements, processing difficulty, and aesthetics.

[0083] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0084] Example 1

[0085] (1) AA5754-O state aluminum alloy coil with a thickness of 1.8mm was selected as the rolling raw material for aluminum alloy variable thickness plates. The cross-sectional structure design of the aluminum alloy variable thickness plates is as follows: Figure 2 As shown, the aluminum alloy variable thickness plate has the following layers from bottom to top: a third equal thickness zone 105 with a height of 300 mm and a thickness of 1.5 mm; a second transition zone 102 with a height of 50 mm and a non-linear thickness change; a second equal thickness zone 104 with a height of 700 mm and a thickness of 1.2 mm; a first transition zone 101 with a height of 50 mm and a non-linear thickness change; and a first equal thickness zone 103 with a height of 1000 mm and a thickness of 0.8 mm.

[0086] (2) Aluminum alloy coils are rolled using a variable gap rolling method. The target thickness of the area to be rolled is defined as C. During the rolling process, the gap between the round rolls B is adjusted in a timely manner to ensure that B = (88-90%) * C. At the same time, a coiling machine is installed on the feed side and the discharge side of the rolls to roll the sheet in the opposite direction. The coiling force of the motors on both sides of the rolls is the same. In addition, during the rolling process, a mixed lubricant of kerosene and vegetable oil (the volume ratio of kerosene to vegetable oil is 1:1) is sprayed at the contact point between the rolls and the sheet. The sheet is rolled in one pass. A thickness gauge is installed at the roll gap exit. A code reader is installed behind the thickness gauge to measure the rolling length of the sheet and control the sheet thickness tolerance to ±0.1mm.

[0087] (3) The rolled aluminum alloy sheet of equal thickness is rolled into a coil with an inner diameter of 250 mm and an outer diameter of 600 mm. The coil is stacked in a bell-type annealing furnace with the center of the coil aligned along the height direction. The temperature is raised to 350°C within 1 hour and held for 2 hours. Then the heating is stopped and the furnace hood is opened to allow the coil to cool slowly to room temperature. The annealed aluminum alloy sheet of equal thickness is then subjected to mechanical pretreatment, chemical pretreatment and anodizing to obtain aluminum alloy cargo box sheet.

[0088] Example 2

[0089] (1) AA5754-O state aluminum alloy coil with a thickness of 1.8mm was selected as the rolling raw material for aluminum alloy variable thickness plates. The cross-sectional structure design of the aluminum alloy variable thickness plates is as follows: Figure 2 As shown, the aluminum alloy variable thickness plate has the following layers from bottom to top: a third equal thickness zone 105 with a height of 300 mm and a thickness of 1.5 mm; a second transition zone 102 with a height of 50 mm and a non-linear thickness change; a second equal thickness zone 104 with a height of 700 mm and a thickness of 1.2 mm; a first transition zone 101 with a height of 50 mm and a non-linear thickness change; and a first equal thickness zone 103 with a height of 1000 mm and a thickness of 0.8 mm.

[0090] (2) Aluminum alloy coils are rolled using a variable gap rolling method. The target thickness of the area to be rolled is defined as C. During the rolling process, the gap between the round rolls B is adjusted in a timely manner to ensure that B = (88-90%) * C. At the same time, a coiling machine is installed on the feed side and the discharge side of the rolls to roll the sheet in the opposite direction. The coiling force of the motors on both sides of the rolls is the same. In addition, during the rolling process, a mixed lubricant of kerosene and vegetable oil (the volume ratio of kerosene to vegetable oil is 1:1) is sprayed at the contact point between the rolls and the sheet. The sheet is rolled in one pass. A thickness gauge is installed at the roll gap exit. A code reader is installed behind the thickness gauge to measure the rolling length of the sheet and control the sheet thickness tolerance to ±0.1mm.

[0091] (3) The rolled aluminum alloy sheet of equal thickness is rolled into a coil with an inner diameter of 250 mm and an outer diameter of 600 mm. The coil is stacked in a bell-type annealing furnace with the center of the coil aligned along the height direction. The temperature is raised to 350°C within 1 hour and held for 2 hours. Then the heating is stopped and the furnace hood is opened to allow the coil to cool slowly to room temperature. The annealed aluminum alloy sheet of equal thickness is then subjected to mechanical pretreatment, chemical pretreatment and anodizing to obtain aluminum alloy cargo box sheet.

[0092] (4) The aluminum alloy cargo box panels are pressed using a molding machine to give them the properties of... Figure 3 The corrugated structure shown has individual corrugations extending vertically.

[0093] Example 3

[0094] The steps are the same as in Example 1, except that 3003-O state aluminum alloy coils are used as rolling raw materials in step (1).

[0095] Example 4

[0096] The steps are the same as in Example 1, except that in step (2), B = (85-87%) * C.

[0097] Example 5

[0098] The steps are the same as in Example 1, except that in step (2), B = (90-92%) * C.

[0099] Example 6

[0100] The steps are the same as in Example 1, except that in step (2), B = (93-95%) * C.

[0101] Example 7

[0102] The steps are the same as in Example 1, except that the volume ratio of kerosene to vegetable oil in step (2) is 1:2.

[0103] Example 8

[0104] The steps are the same as in Example 1, except that the volume ratio of kerosene to vegetable oil in step (2) is 1:3.

[0105] Example 9

[0106] The steps are the same as in Example 1, except that the volume ratio of kerosene to vegetable oil in step (2) is 1:4.

[0107] Example 10

[0108] The steps are the same as in Example 1, except that the volume ratio of kerosene to vegetable oil in step (2) is 1:5.

[0109] Example 11

[0110] The steps are the same as in Example 1, except that in step (2), kerosene is sprayed at the contact point between the roll and the plate as a lubricant.

[0111] Example 12

[0112] The steps are the same as in Example 1, except that in step (3), the aluminum alloy plate of equal thickness is heated to 250°C within 2 hours in a bell-type annealing furnace and kept at that temperature for 6 hours.

[0113] Example 13

[0114] The steps are the same as in Example 1, except that in step (3), the aluminum alloy plate of equal thickness is heated to 300°C within 2 hours in a bell-type annealing furnace and kept at that temperature for 5 hours.

[0115] Example 14

[0116] The steps are the same as in Example 1, except that in step (3), the aluminum alloy plate of equal thickness is heated to 350°C within 1.5 hours in a bell-type annealing furnace and held for 4 hours.

[0117] Example 15

[0118] The steps are the same as in Example 1, except that in step (3), the aluminum alloy plate of equal thickness is heated to 400°C within 1 hour and held for 3 hours in a bell-type annealing furnace.

[0119] Example 16

[0120] The steps are the same as in Example 1, except that in step (3), the aluminum alloy plate of equal thickness is heated to 450°C within 1 hour and held for 2 hours in a bell-type annealing furnace.

[0121] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An aluminum alloy cargo box panel, characterized in that, The aluminum alloy cargo box panels are used to enclose and form the cargo box; The aluminum alloy cargo box panel has multiple transition zones extending in the vertical direction, and the thickness of the aluminum alloy cargo box panel in the transition zone gradually decreases from bottom to top in the cargo box. The aluminum alloy cargo box plate is also provided with multiple equal thickness zones extending in the vertical direction. The equal thickness zones are adjacent to the transition zone, and the thickness is the same at the connection between the equal thickness zones and the transition zone. Multiple transition zones and multiple equal-thickness zones are alternately arranged; The aluminum alloy cargo box panels are pressed into a corrugated structure, and the individual corrugations in the corrugated structure extend in the vertical direction.

2. The aluminum alloy cargo box panel as described in claim 1, characterized in that, The aluminum alloy cargo box panels are made from aluminum alloy plates of equal thickness, and are rolled into aluminum alloy plates of varying thickness in one pass using round rollers with varying gaps.

3. The aluminum alloy cargo box panel as described in claim 1, characterized in that, The transition zone includes a linear transition zone with linearly varying thickness and / or a curved transition zone with non-linearly varying thickness.

4. The aluminum alloy cargo box panel as described in claim 1, characterized in that, The maximum thickness of the aluminum alloy cargo box sheet is A1, and the minimum thickness of the aluminum alloy truck sheet is A2, where A1 / A2≤3.

5. An aluminum alloy cargo box, characterized in that, The aluminum alloy cargo box includes cargo box side panels, which are aluminum alloy cargo box sheet materials as described in any one of claims 1 to 4.

6. The aluminum alloy cargo box as described in claim 5, characterized in that, The aluminum alloy cargo box also includes multiple uprights extending in the vertical direction, and the uprights are fixedly connected to the inner side of the side panel of the aluminum alloy cargo box.

7. The aluminum alloy cargo box as described in claim 6, characterized in that, The aluminum alloy cargo box also includes a protective panel, which is detachably installed on the uprights.

8. A truck, characterized in that, The truck includes an aluminum alloy cargo box as described in any one of claims 5 to 7.

9. A method for preparing aluminum alloy cargo box panels, characterized in that, The aluminum alloy cargo box panels are used to enclose and form the cargo box. The method for preparing the aluminum alloy cargo box panels includes the following steps: Aluminum alloy plate of equal thickness is selected as raw material, and aluminum alloy plate of equal thickness is rolled into shape in one pass by a circular roller variable gap rolling method to obtain aluminum alloy plate of variable thickness. The aluminum alloy variable thickness plate is subjected to annealing, mechanical pretreatment, chemical pretreatment, and anodizing in sequence to obtain an aluminum alloy cargo box plate with variable thickness. The aluminum alloy cargo box plate has multiple transition zones extending in the vertical direction, and the thickness of the aluminum alloy cargo box plate in the transition zones gradually decreases from bottom to top of the cargo box. The aluminum alloy cargo box plate also has multiple equal thickness zones extending in the vertical direction, adjacent to the transition zones, and the thickness is consistent at the connection between the equal thickness zones and the transition zones. The multiple transition zones and the multiple equal thickness zones are arranged alternately. The aluminum alloy cargo box sheet is pressed to give it a corrugated structure, wherein each corrugation in the corrugated structure extends in the vertical direction.

10. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, The aluminum alloy plate of equal thickness is made of 3XXX series aluminum alloy or 5XXX series aluminum alloy.

11. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, The aluminum alloy plate of equal thickness is made of AA5754-O state aluminum alloy.

12. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, In the step of forming the aluminum alloy plate of equal thickness in one pass using a variable gap rolling mill: The roll gap of the circular roller is B, and the target thickness of the rolling area of ​​the aluminum alloy plate of equal thickness is C, where B = (85-95%) * C.

13. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, In the step of forming the aluminum alloy plate of equal thickness in one pass using a variable gap rolling mill: Both sides of the roller are equipped with coiling machines, which simultaneously roll the aluminum alloy plate of equal thickness in reverse.

14. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, In the step of rolling the aluminum alloy plate of equal thickness using variable gap rolling mill: Lubricant is sprayed at the contact point between the roller and the aluminum alloy plate of equal thickness.

15. The method for preparing aluminum alloy cargo box panels as described in claim 14, characterized in that, The lubricant includes kerosene and vegetable oil, and the volume ratio of kerosene to vegetable oil is 1:0 to 1:

5.

16. The method for preparing aluminum alloy cargo box panels as described in claim 9, characterized in that, The annealing step for the aluminum alloy variable thickness plate includes: The aluminum alloy thickened plate is placed in a bell-type annealing furnace, heated to 250-450°C within 2 hours, held at that temperature for 2-6 hours, and then the heating is stopped to allow the aluminum alloy thickened plate to cool naturally in the furnace.

Images