Magnesium alloy avionics equipment with corrosion protection capability

Abstract

According to the magnesium alloy avionics equipment with the corrosion protection capability, on the premise that the overall structural space of a product is limited, the shell and the cover plate which are made of magnesium alloy materials and provided with micro-arc oxidation films are adopted, and the nano coating is additionally arranged on the surface of the magnesium alloy, so that the corrosion protection capability of the magnesium alloy avionics equipment is improved. A contact channel between the corrosive medium and the magnesium alloy base material is blocked; and meanwhile, by means of increasing a gap between the shell and the mounting bracket and forming an open type solution drainage groove in a supporting bottom frame of the mounting bracket so that an acid salt mist solution cannot be left in an area between the shell and the mounting bracket and the like, corrosion between dissimilar metals is avoided, the corrosion resistance is improved, and the product weight is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of avionics equipment protection technology, specifically relating to a magnesium alloy avionics equipment with corrosion protection capabilities. Background Technology

[0002] The requirement for lightweight avionics (such as inertial navigation / attitude products) is becoming increasingly mainstream, and the requirements for corrosion protection of aircraft equipment adapted to marine environments and climates are also becoming increasingly stringent. Therefore, weight reduction and corrosion protection of such products have become a key focus of structural design.

[0003] In recent years, magnesium alloys have seen rapid development as a superior choice for product weight reduction. However, they still suffer from poor corrosion resistance, especially being highly sensitive to galvanic corrosion (dissimilar metals in direct contact with air or solution will form a galvanic cell chemical reaction, causing corrosion; magnesium alloys have a galvanic corrosion rating of 2 with other metals, indicating severe corrosion). The corrosion of magnesium is essentially an electrochemical and chemical process in which magnesium is oxidized to magnesium oxide or magnesium hydroxide. Since the electrochemical potential and free energy of magnesium and its compounds in different valence states are much lower than those of elemental magnesium, the corrosion process of magnesium is spontaneous, easily occurs, and is irreversible, requiring appropriate protective measures.

[0004] Micro-arc oxidation technology, as a post-treatment protective technique, can improve the corrosion resistance of magnesium alloys and expand their application range. Typically, a coating is applied after micro-arc oxidation to further enhance the corrosion resistance. However, the commonly used composite coating consisting of H06-3 primer and F04-60 topcoat is difficult to meet the requirements of a 192-hour acidic salt spray environment, resulting in poor corrosion protection. Corrosion protection is not only related to the protective methods but also to the product structure.

[0005] Therefore, this utility model designs a product that combines lightweight and corrosion protection, and the design concept of this product is also applicable to similar inertial navigation / attitude products. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies and provide a magnesium alloy avionics device with corrosion protection capabilities.

[0007] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0008] A magnesium alloy avionics device with corrosion protection capability is characterized by comprising core electronic components (specifically, the corresponding circuit boards and core sensors can be selected according to the function of the avionics device), housing, cover plate, mounting bracket, baffle, fastening sleeve, and fastening components.

[0009] The cover plate and the housing are assembled to form a rectangular mounting shell for placing core electronic components; both the cover plate and the housing are made of magnesium alloy with a micro-arc oxide film, and the surface of the magnesium alloy is also coated with a 0.15-0.21mm nano-coating.

[0010] The mounting bracket includes fastening lugs and a rectangular support base frame; the fastening lugs are vertically arranged on the upper surface of one of the support rods on the support base frame, and fastening holes are provided on the fastening lugs; positioning holes and mounting holes are arranged side by side on the support rod opposite to the support rod where the fastening lugs are located; guide strips are provided on the upper surface of the other pair of support rods of the support base frame, the two guide strips are parallel to each other and the distance between them is greater than the width of the shell; all support rods of the support base frame are provided with open solution drainage channels;

[0011] A fastening sleeve is bonded to the outer side of one wall of the housing, and a threaded hole is provided on the opposite wall; the baffle is provided with corresponding holes at the positions of the positioning hole, the mounting hole and the threaded hole.

[0012] Guided by two guide bars, the housing is fixed to the mounting bracket from both ends through the cooperation of fastening ears, fastening sleeves, baffles, supporting bottom frame and fastening components, and there is at least a 2mm gap between its bottom surface and the supporting bottom frame.

[0013] Furthermore, the nano-coating on the magnesium alloy surface is a nano-coating applied using a cross-hatching method. It comprises three layers from bottom to top, with thicknesses of 30-50 μm, 60-80 μm, and 60-80 μm respectively. The first nano-coating layer is thinner, facilitating good adhesion. The cross-hatching method, also known as the horizontal-vertical cross-hatching method, requires that each subsequent coat of paint be applied only after the previous coat has reached a surface-dry state (approximately 2 hours at room temperature).

[0014] Furthermore, for a more secure installation, there are two fastening lugs, which are respectively located at both ends of the support rod.

[0015] Furthermore, two fastening sleeves are bonded to the outer wall of the housing near the fastening ear, corresponding to the position of the fastening ear (because the fastening sleeves are bonded to the housing with adhesive, there is physical isolation, so no matter what metal the fastening sleeves are made of, there will be no dissimilar metal corrosion between the housing and the fastening sleeves), and three threaded holes are provided on the wall away from the fastening ear.

[0016] Multiple strip-shaped heat dissipation grooves are provided on the outer sides of the four walls of the shell to increase the surface area of ​​the shell and facilitate heat dissipation.

[0017] Furthermore, the baffle is generally in the shape of an inverted trapezoid, with a hole (also a threaded hole) near the top that mates with the threaded hole in the housing, and a through hole near the bottom that mates with the positioning hole and the mounting hole. In other words, during installation, the upper end of the baffle connects to the housing, and the lower end connects to the supporting base frame. Because the housing is coated with a nano-coating, no dissimilar metal corrosion will occur between the two, regardless of the baffle's material, and the baffle also provides some protection.

[0018] Furthermore, the housing and the cover plate are fastened together by screws, and an insulating washer is provided between the screws and the housing and the cover plate to prevent frequent tightening and loosening of the screws from causing contact between dissimilar metals and resulting in corrosion.

[0019] Furthermore, the fastening assembly includes a first fastener, a second fastener, and a third fastener;

[0020] The first fastener is used to connect the fastening lug and the fastening sleeve;

[0021] The second fastener is used to connect the baffle to the supporting base frame;

[0022] The third fastener is used to connect the baffle to the housing.

[0023] Furthermore, the first and second fasteners are both cylindrical pins, and the third fastener is a screw.

[0024] Furthermore, for a more secure connection, the fastening sleeve is made of stainless steel.

[0025] Advantages of this utility model:

[0026] 1. Under the premise of limited overall product space, this utility model adopts a shell and cover plate made of magnesium alloy with micro-arc oxidation film, and adds a nano-coating to the surface of magnesium alloy to block the contact channel between corrosive media and magnesium alloy substrate; at the same time, by increasing the gap between shell and mounting bracket, and setting an open solution drainage channel in the support bottom frame to prevent acidic salt spray solution from stagnating in the area between shell and mounting bracket, corrosion between dissimilar metals is avoided, corrosion resistance is improved, and product weight is reduced.

[0027] 2. This utility model adds an insulating washer between the screw and the housing and cover plate, which can prevent corrosion caused by direct contact between dissimilar metals.

[0028] 3. This utility model can not only improve the corrosion protection capability of products under development, but also provide more design ideas for lightweight design and corrosion protection design of similar inertial navigation / attitude and bearing products, thereby reducing product weight and improving product protection performance. Attached Figure Description

[0029] Figure 1This is a schematic diagram of the overall structure of the avionics equipment of this utility model;

[0030] Figure 2 This is a schematic diagram of the installation structure of the housing and mounting bracket in the avionics equipment of this utility model;

[0031] Figure 3 This is a schematic diagram of the housing structure in the avionics equipment of this utility model;

[0032] Figure 4 This is a schematic diagram of the mounting bracket structure in the avionics equipment of this utility model.

[0033] The attached figures are labeled as follows:

[0034] 1-Cylindrical pin, 2-Fasting sleeve, 3-Mounting bracket, 4-Housing shell, 5-Screw I, 6-Cover plate, 7-Baffle, 8-Gap, 9-Drainage groove, 10-Supporting base frame, 11-Fasting ear, 12-Fasting hole, 13-Positioning hole, 14-Through hole, 15-Fasting sleeve bonding position, 16-Guide strip, 17-Heat dissipation groove, 18-Screw II, 19-Mounting hole. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0036] like Figure 1-4 As shown, a magnesium alloy avionics device with corrosion protection capability includes a core electronic component (not shown in the figure), a housing, a cover plate, a mounting bracket, a baffle, a fastening sleeve, and a fastening assembly.

[0037] The cover plate and housing are assembled and fastened together by screw I (an insulating washer is provided between screw I and the housing and cover plate), forming a rectangular mounting shell for housing the core electronic components. Both the cover plate and housing are made of magnesium alloy with a micro-arc oxide film, and the magnesium alloy surface is coated with a 0.15-0.21 mm nano-coating (0.21 mm in this embodiment). This nano-coating is applied using a cross-hatching method and consists of three layers from bottom to top, with thicknesses of 30-50 μm, 60-80 μm, and 60-80 μm respectively (in this embodiment, the thicknesses of the three layers from bottom to top are 50 μm, 80 μm, and 80 μm). The first nano-coating layer is thinner, facilitating good adhesion. The cross-hatching method, also known as the horizontal-vertical cross-hatching method, requires that the previous coat of paint be surface dry before applying the next coat (the surface drying time for each coat at room temperature is approximately 2 hours). Because of their small size, nanoparticles can easily penetrate into irregular pores when coated on titanium alloy surfaces, making the titanium alloy surface flatter and more uniform, and preventing other media from penetrating.

[0038] The mounting bracket includes two fastening lugs and a rectangular support base frame. The two fastening lugs are vertically positioned at both ends of the upper surface of one of the support rods on the support base frame, and each lug has a fastening hole. On the support rod opposite the fastening lugs, a positioning hole and a mounting hole are located at the same horizontal plane in the middle, and the axes of the fastening hole, positioning hole, and mounting hole are parallel to the other pair of support rods. Guide strips are located near the edge of the middle of the upper surface of the other pair of support rods on the support base frame. The two guide strips are parallel to each other and the distance between them is greater than the width of the housing, preventing direct contact between the two metals after installation and thus avoiding corrosion between dissimilar metals. All support rods on the support base frame are equipped with open solution drainage channels. Specifically, the number of channels can be adjusted according to the length of the support rod. Longer support rods can have multiple open solution drainage channels spaced apart while ensuring support strength, while shorter support rods can have only one open solution drainage channel spaced apart. This prevents acidic salt spray solution from accumulating in the area between the housing and the mounting bracket, and avoids the presence of solution between dissimilar metals, effectively preventing direct contact and galvanic cell reactions that could cause corrosion.

[0039] Two fastening sleeve bonding positions are provided on the outer side of one wall of the housing, where two fastening sleeves are bonded. Three threaded holes are provided on the opposite wall surface. Furthermore, multiple strip-shaped heat dissipation grooves are provided on the outer sides of all four walls of the housing to increase the surface area and facilitate heat dissipation. The distance between the two fastening sleeves is the same as the distance between the fastening holes on the two fastening lugs. The height of the two fastening sleeves on the housing ensures that the distance between the bottom of the housing and the supporting base frame is not less than 2mm after installation.

[0040] The baffle is shaped like an inverted trapezoid. Near the top, there is a threaded hole that mates with the threaded hole in the housing, and near the bottom, there is a through hole that mates with the positioning hole and the mounting hole. In other words, during installation, the upper end of the baffle connects to the housing, and the lower end connects to the supporting base frame. Because the housing is coated with a nano-coating, no dissimilar metal corrosion will occur between the two, regardless of the baffle's material, and the baffle also provides a certain degree of protection.

[0041] The fastening assembly includes a first fastener, a second fastener, and a third fastener; wherein, the first fastener is used to connect the fastening lug and the fastening sleeve, and is a cylindrical pin; the second fastener is used to connect the baffle and the supporting base frame, and is a cylindrical pin; the third fastener is used to connect the baffle and the housing, and is a screw II.

[0042] Guided by two guide bars, the housing is pushed into the mounting bracket. The first fastener connects the fastening lug to the fastening sleeve, the second fastener connects the baffle to the supporting base frame, and the third fastener connects the baffle to the housing. In this way, the entire housing is mounted on the mounting bracket and suspended above the supporting base frame. It is isolated from the fastening sleeve by adhesive, from the baffle by a nano-coating, and there is a gap of at least 2mm between it and the supporting base frame. There is also no direct contact between it and the guide bars, which can effectively avoid corrosion between dissimilar metals and improve corrosion resistance.

[0043] The above description is only a specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present utility model, and these modifications or substitutions should all be covered within the protection scope of the present utility model.

Claims

1. A magnesium alloy avionics device with corrosion protection capability, characterized in that: This includes core electronic components, housing, cover, mounting brackets, baffles, fastening sleeves, and fastening components; The cover plate and the housing are assembled to form a rectangular mounting shell for placing core electronic components; both the cover plate and the housing are made of magnesium alloy with a micro-arc oxide film, and the surface of the magnesium alloy is also coated with a 0.15-0.21mm nano-coating. The mounting bracket includes fastening lugs and a rectangular support base frame; the fastening lugs are vertically arranged on the upper surface of one of the support rods on the support base frame, and fastening holes are provided on the fastening lugs; positioning holes and mounting holes are arranged side by side on the support rod opposite to the support rod where the fastening lugs are located; guide strips are provided on the upper surface of the other pair of support rods of the support base frame, the two guide strips are parallel to each other and the distance between them is greater than the width of the shell; all support rods of the support base frame are provided with open solution drainage channels; A fastening sleeve is bonded to the outer side of one wall of the housing, and a threaded hole is provided on the opposite wall; the baffle is provided with corresponding holes at the positions of the positioning hole, the mounting hole and the threaded hole. Guided by two guide bars, the housing is fixed to the mounting bracket from both ends through the cooperation of fastening ears, fastening sleeves, baffles, supporting bottom frame and fastening components, and there is at least a 2mm gap between its bottom surface and the supporting bottom frame.

2. The magnesium alloy avionics device with corrosion protection capability according to claim 1, characterized in that: The nano-coating on the magnesium alloy surface is a nano-coating applied by a cross-spraying method, which consists of three layers from bottom to top, with thicknesses of 30-50μm, 60-80μm, and 60-80μm, respectively.

3. The magnesium alloy avionics device with corrosion protection capability according to claim 1 or 2, characterized in that: There are two fastening lugs, which are respectively located at both ends of the support rod.

4. The magnesium alloy avionics device with corrosion protection capability according to claim 3, characterized in that: Two fastening sleeves are bonded to the outer side of the wall near the fastening ear, corresponding to the position of the fastening ear, and three threaded holes are provided on the wall away from the fastening ear; Multiple strip-shaped heat dissipation grooves are provided on the outer sides of the four walls of the housing.

5. The magnesium alloy avionics device with corrosion protection capability according to claim 4, characterized in that: The baffle is generally in the shape of an inverted trapezoid, with a hole near the top that mates with the threaded hole in the housing, and a through hole near the bottom that mates with the positioning hole and the mounting hole.

6. The magnesium alloy avionics device with corrosion protection capability according to claim 5, characterized in that: The housing and the cover plate are fastened together by screws; an insulating washer is provided between the screws and the housing and the cover plate.

7. The magnesium alloy avionics device with corrosion protection capability according to claim 6, characterized in that: The fastening assembly includes a first fastener, a second fastener, and a third fastener; The first fastener is used to connect the fastening lug and the fastening sleeve; The second fastener is used to connect the baffle to the supporting base frame; The third fastener is used to connect the baffle to the housing.

8. The magnesium alloy avionics device with corrosion protection capability according to claim 7, characterized in that: The first and second fasteners are both cylindrical pins, and the third fastener is a screw.

9. The magnesium alloy avionics device with corrosion protection capability according to claim 8, characterized in that: The fastening sleeve is made of stainless steel.

Images