A device for uniformly ion nitriding a layer without power-assisted heating
By using a non-powered auxiliary heating fixture in the ion nitriding furnace to heat the outer parts through heat conduction, the problem of uneven heating between the inner and outer sides of the parts was solved, the uniformity of part hardness and the pass rate were improved, and the modification process was simplified.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBEI HUABEI DIESEL ENGINE
- Filing Date
- 2025-05-13
- Publication Date
- 2026-06-09
AI Technical Summary
In existing ion nitriding furnaces, uneven layer depth occurs on the inner and outer sides of parts during the heating process, resulting in uneven hardness and low pass rate. Existing modification methods are cumbersome and costly.
A non-powered auxiliary heating fixture is used to heat the outer parts through heat conduction, improving the uniformity of furnace temperature. The cylindrical auxiliary heating fixture, made of solid carbon steel, is placed on the outer ring of the fixture plate at a distance of more than 10mm from the workpiece to be nitrided to ensure uniform heating.
It improves the uniformity of the ion nitriding layer on the parts, ensures a 100% pass rate for the parts, simplifies the modification process, and reduces equipment modification costs.
Smart Images
Figure CN224337685U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of heat treatment equipment for metal materials, and specifically relates to a device for heating a uniform ion nitriding layer without power assistance. Background Technology
[0002] Ion nitriding utilizes the principle of glow discharge. Ammonia gas is introduced into a vacuum furnace, with the furnace body serving as the anode and the metal workpiece to be treated as the cathode. When electricity is applied, the ammonia gas is ionized into nitrogen ions and hydrogen ions, which bombard the workpiece at high speed to heat it. The ion bombardment of the workpiece surface produces atomic sputtering. Through adsorption and diffusion, nitrogen ions penetrate into the surface of the workpiece to form a nitrided layer, thus achieving surface hardening.
[0003] The ion nitriding furnace has a double-layer furnace body with circulating water cooling in the middle. The outer layer of the furnace body has a temperature of 50±5℃, resulting in a lower temperature on the outer side near the furnace body. This reduced ion activity leads to uneven layer depth on the inner and outer sides of the part during ion nitriding. The poor uniformity of the nitriding furnace is a key reason for operational difficulties and high rework rates. Figure 1 As shown in the figure, the upper and lower layers of workpieces in the ion nitriding furnace are shown, with the lower layer... Number and upper level The workpiece at position number 1 has relatively low hardness, mainly because the layer depth is uneven on the inner and outer sides of the part during ion nitriding, resulting in localized low hardness in some finished parts, with a failure rate of approximately 66.7%.
[0004] Existing technologies report solutions such as adding heat insulation screens, raising the cooling water inlet position to reduce heat loss, and installing ammonia pressure regulating valves to prevent uneven workpiece temperature caused by direct ammonia blowing. While these modifications can improve temperature uniformity within the ion nitriding furnace, the process is overly complex and requires equipment modifications. Utility Model Content
[0005] The purpose of this invention is to design a simpler, more convenient, and more economical auxiliary heating method to assist tooling in heat conduction heating of outer parts, improve the problem of low temperature on the outer side near the furnace body, uniform furnace temperature, improve the uniformity of the ion nitriding layer of the parts, and ensure the part qualification rate.
[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:
[0007] A device for heating a uniform ion nitriding layer without power assistance includes a furnace hood, a base, a cathode disk disposed on the base, and a tooling disk disposed on the cathode disk. It also includes a plurality of auxiliary heating tools placed on the tooling disk. The height of the auxiliary heating tools is the same as the height of the workpiece to be nitrided or the same as the height of the nitriding tool on which the workpiece to be nitrided is placed.
[0008] A further improvement of this utility model is that the auxiliary heating fixture is placed on the outer ring of the fixture plate, on the outside of the nitriding fixture or the workpiece to be nitrided, and the auxiliary heating fixture is cylindrical in shape.
[0009] A further improvement of this utility model is that the auxiliary heating fixture is made of solid carbon steel with a flat bottom and a smooth top without sharp edges.
[0010] A further improvement of this utility model is that: at least four auxiliary heating fixtures are placed evenly on the outer ring of the fixture tray, and the distance between the auxiliary heating fixtures and the nitriding fixtures or the workpiece to be nitrided is more than 10mm.
[0011] A further improvement of this utility model's technical solution lies in that: the minimum diameter of the auxiliary heating fixture is... 100mm.
[0012] A further improvement of this utility model is that the auxiliary heating fixture is made of 45# steel and has a rounded top.
[0013] A further improvement of this utility model is that it also includes a base for holding the auxiliary heating fixture, the base including a circular base plate and a cylindrical tube disposed on the base plate, the inner diameter of the cylindrical tube being larger than the diameter of the auxiliary heating fixture.
[0014] The technological advancements achieved by this utility model due to the adoption of the above technical solution are as follows:
[0015] This application presents a device for non-powered auxiliary heating to uniformly ion-nitrided layers. It offers a simpler, more convenient, and economical auxiliary heating method. The auxiliary heating fixture uses heat conduction to heat the outer parts, improving the problem of lower temperatures near the furnace body on the outer side. This results in a more uniform furnace temperature, increasing the uniformity of the ion-nitrided layer and ensuring a higher yield rate. This application requires no further modifications to the nitriding furnace, and the method is simpler and more effective. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the workpiece arrangement in an existing ion nitriding furnace;
[0017] Figure 2 This is a schematic diagram of the ion nitriding furnace of this utility model;
[0018] Figure 3 This is a schematic diagram of the arrangement of the ion nitrogen chemical processing equipment and auxiliary heating equipment of this utility model;
[0019] Figure 4 This is a schematic diagram of the base;
[0020] The components include: 1. Furnace hood; 2. Base; 3. Cathode plate; 4. Tooling plate; 5. Nitrogenation tooling; and 6. Auxiliary heating tooling. Detailed Implementation
[0021] The present invention will be further described in detail below with reference to embodiments:
[0022] Example 1
[0023] like Figure 2 , 3 As shown, an apparatus for generating a uniform ion nitriding layer without power assistance includes a furnace hood 1, a base 2, a cathode disk 3 mounted on the base, and a tooling disk 4 mounted on the cathode disk. It also includes several auxiliary heating fixtures 6 placed on the tooling disk 4. The height of the auxiliary heating fixtures 6 is the same as the height of the workpiece to be nitrided or the same as the height of the nitriding fixture 5 on which the workpiece is placed. That is, the height of the auxiliary heating fixtures 6 is the same as the height of the workpiece to be nitrided placed on the tooling disk 4. If the workpiece is placed inside the nitriding fixture 5 on the tooling disk 4, then the height of the auxiliary heating fixtures 6 is the same as the height of the nitriding fixture 5. The auxiliary heating fixtures 6 are placed around the perimeter of the tooling disk, are cylindrical in shape, made of solid carbon steel, have a flat bottom, and no sharp edges at the top.
[0024] When in use, place the tooling tray 4 on the cathode tray 3, then place several nitriding fixtures 5 on the tooling tray 4 in sequence, and then place the auxiliary heating fixtures 6 on the outer ring of the nitriding fixtures 5 on the tooling tray 4. Depending on the actual production situation, if the tooling tray 4 is large enough or there is enough space on the tooling tray 4, the number of auxiliary heating fixtures 6 can be increased appropriately, and the auxiliary heating fixtures 6 should be evenly placed on the outer ring of the tooling tray 4.
[0025] When the tooling tray 4 is small or has a large number of workpieces, at least four auxiliary heating fixtures 6 should be provided, evenly distributed around the outer ring of the tooling tray 4. The distance between the auxiliary heating fixtures 6 and the nitriding fixture 5 or the workpiece to be nitrided should be at least 10mm. The minimum diameter of the auxiliary heating fixtures 6 is [missing information]. 100mm.
[0026] If the inner hole of the workpiece needs to be nitrided, a nitriding fixture 5 is required, and the workpiece to be nitrided is placed inside the nitriding fixture 5. If the workpiece to be processed is a gear or other component, the workpiece is placed directly on the fixture tray 4, and the auxiliary heating fixture 6 is placed around the workpiece, with the height of the auxiliary heating fixture 6 being the same as the height of the workpiece.
[0027] Example 2
[0028] The difference between this embodiment and Embodiment 1 is that it also includes a base, such as... Figure 4As shown, the base is used to hold the auxiliary heating fixture 6. The base includes a circular base plate and a cylindrical tube set on the base plate. The inner diameter of the cylindrical tube is larger than the diameter of the auxiliary heating fixture 6. In use, the base is placed on the outer ring of the fixture tray 4, and the auxiliary heating fixture 6 is placed inside the base. The base is made of carbon steel, and whether the base is needed depends on the actual production situation.
[0029] Example 3
[0030] This embodiment is the same as Embodiment 1, and is an experimental example. The device for producing a uniform ion nitride layer without power assistance, as described in this application, is used for trial production. The auxiliary heating fixture 6 has the following dimensions: The material is made of Twelve steel components are placed on fixture 4. The workpieces to be nitrided are placed inside nitriding fixture 5, which is positioned in the center of the fixture tray. Auxiliary heating fixtures 6 are placed around its outer ring, evenly distributed. (Reference) Figure 1 For example, in the lower level arrive Auxiliary heating fixtures 6 are set around the outer ring of the workpiece or nitriding fixture 5. The auxiliary heating fixtures 6 are evenly distributed. To make full use of space, the auxiliary heating fixtures 6 can be set in the outer ring between two workpieces, that is, the line connecting the outer ring auxiliary heating fixtures 6 and... arrive The circles formed by the workpieces are concentric circles, but the diameter of the circle connecting the auxiliary heating fixture 6 is greater than... arrive The diameter of the circle formed by the workpieces.
[0031] After one year of production verification, more than 2,000 water-cooled parts were processed. By comparison, the ion nitriding layer depth of the workpieces using the device of this application was 0.55-0.65mm, which meets the requirement of 0.52-0.75mm. After grinding, the hardness of the products met the process requirements. The nitriding of the workpieces was uniform, with a pass rate of 100% and good results.
[0032] The non-powered auxiliary heating device for ion nitriding of this invention overcomes the limitations of resistance-assisted heating in ion nitriding furnaces. It is not limited by product type and effectively utilizes the heat generated by ion bombardment tooling. The tooling heats surrounding parts through heat conduction, reducing heat loss near the furnace body. By heating outer parts through heat conduction from the non-powered auxiliary tooling, the problem of lower temperatures near the furnace body on the outer side is addressed, resulting in a more uniform furnace temperature and improved uniformity of the ion nitriding layer on the gas-filled parts.
Claims
1. A device for heating a uniform ion nitrided layer without power assistance, comprising a furnace hood (1), a base (2), a cathode disk (3) disposed on the base, and a tooling disk (4) disposed on the cathode disk, characterized in that: It also includes several auxiliary heating fixtures (6) placed on the fixture tray (4), the height of which is the same as the height of the workpiece to be nitrided or the height of the nitriding fixture (5) on which the workpiece to be nitrided is placed.
2. The device for heating a uniform ion nitriding layer without power assistance according to claim 1, characterized in that: The auxiliary heating fixture (6) is placed on the outer ring of the fixture plate (4), the outside of the nitriding fixture (5) or the workpiece to be nitrided, and the auxiliary heating fixture (6) is cylindrical in shape.
3. The device for heating a uniform ion nitriding layer without power assistance according to claim 2, characterized in that: The auxiliary heating fixture (6) is made of solid carbon steel with a flat bottom and a smooth top without sharp edges.
4. The device for heating a uniform ion nitriding layer without power assistance according to claim 1, characterized in that: At least four auxiliary heating fixtures (6) are placed evenly on the outer ring of the fixture plate (4), and the distance between the auxiliary heating fixtures (6) and the nitriding fixtures (5) or the workpiece to be nitrided is more than 10 mm.
5. The device for heating a uniform ion nitriding layer without power assistance according to claim 1, characterized in that: The minimum diameter of the auxiliary heating fixture (6) is Φ100mm.
6. The apparatus for heating a uniform ion nitriding layer without power assistance according to claim 5, characterized in that: The auxiliary heating fixture (6) is made of 45# steel and has a rounded top.
7. The device for heating a uniform ion nitriding layer without power assistance according to claim 1, characterized in that: It also includes a base for holding the auxiliary heating fixture (6), the base including a circular base plate and a cylindrical tube disposed on the base plate, the inner diameter of the cylindrical tube being larger than the diameter of the auxiliary heating fixture (6).