During the use of metal workpieces in casting, forging, welding and cutting, due to the action of heat and cold, mechanical deformation, residual stress is generated inside the workpiece, resulting in the workpiece being in an unstable state, reducing the dimensional stability and mechanical physical properties of the workpiece. The workpiece undergoes stress deformation and failure during service, and the dimensional accuracy is not guaranteed. In order to eliminate residual stress, thermal aging and natural aging have been used in the past. However, these two methods have many drawbacks: the natural aging cycle is too long, the floor space is large, and it is not suitable for mass production; the heat aging has high usage fee, and the floor space is large, the auxiliary equipment is high, the energy consumption is high, and the furnace temperature is high. The control is difficult, the workpiece is easy to oxidize, the cleaning workload is increased, and it is easy to be cracked due to uneven heating, and new stress is generated during the cooling process. In addition, the thermal aging treatment has poor working conditions, polluting the environment, and the level of mechanization automation is not high. . Vibration aging significantly saves energy, reduces costs, and shortens cycle times. Compared with thermal aging, vibration aging saves more than 90% of aging cost, saves more than 95%, saves more than 90% of investment, natural aging cycle takes half a year or two, heat aging takes 1-2 days, and vibration aging usually takes only half an hour. The maximum length is no more than 1 hour. The device is light and easy to carry, simple in process, adaptable, and highly automated, and is not limited by the size, weight and location of the workpiece.
Vibration aging adapts to the requirements of energy and environmental protection in modern industrial society. In some respects, it has replaced the trend of traditional heat aging and has become a revolutionary high-tech. Has caused great concern and interest in the machinery manufacturing industry. In the past two or three decades, it has been widely used in the world.
First, vibration aging overview
1, the principle of vibration aging
The vibration elimination stress is abbreviated as VSR (Vibratory Stress Relief), which uses a controlled vibration energy to treat a metal workpiece to eliminate the residual stress of the workpiece.
A large number of application examples at home and abroad have proved that vibration aging has a good effect on the dimensional accuracy of stable parts. However, there has been no systematic and satisfactory explanation for the mechanism of vibration aging to stabilize dimensional accuracy.
From a macroscopic point of view, vibration aging causes the plastic deformation of the part, reduces and homogenizes the residual stress and improves the resistance of the material to deformation. This is undoubtedly the basic reason for the dimensional accuracy of the part. From the analysis of residual stress relaxation and part deformation, the existence and instability of residual stress cause stress relaxation and redistribution, resulting in plastic deformation of the part. Thermal aging is often used to eliminate and reduce residual stresses, especially dangerous peak stresses. Vibration aging can also reduce residual stress. The residual stress of the part after vibration treatment can be reduced by 20-30%, sometimes 50-60%, and the peak stress can be reduced to equalize the stress distribution.
In addition to residual stress values, another important factor in determining the dimensional stability of a part is the relaxed stiffness or the ability of the part to resist deformation. Sometimes, although the part has a large residual stress, it is not resistant to deformation and does not cause large deformation. In this respect, vibration aging also shows a significant effect. It can be seen from the results of the vibration aging loading test that the anti-deformation ability of the vibration aging member is not only higher than that of the unaged parts, but also higher than the parts subjected to the heat aging treatment. The material is strengthened by vibration to stabilize the dimensional accuracy of the part.
From a microscopic point of view, vibration aging can be considered as an additional stress applied to the part in the form of a cyclic load. It is well known that the materials used in engineering are not ideal elastomers, and there are different types of microscopic defects in the interior. In the cast iron, there are a large number of graphites of various shapes and shapes for cutting metal bodies. Therefore, whether it is steel, cast iron or other metals, there are different levels of stress concentration near the microscopic defects. When subjected to vibration, the alternating stress applied to the part is superimposed on the residual stress in the part. When the result of the stress superposition reaches a certain value, the most severe part of the stress concentration will exceed the yield limit of the material and plastically deform. This plastic deformation reduces the residual stress peaks at this point and strengthens the metal matrix. Then, the vibration will have the same effect on other parts with more severe stress concentration until the algebra of the additional stress and residual stress of the vibration and the plastic deformation of any part cannot be caused. At this time, the vibration will no longer be eliminated and homogenized. Residual stress and the role of strengthening metals.
Vibration aging process treatment site map
Controller: A device that controls the exciter to generate the required vibration energy and frequency.
Exciter: A device that is rigidly connected to a workpiece to generate an exciting force that causes the workpiece to vibrate. It consists of a motor and an eccentric wheel.
Sensor: A device that acquires information about the vibration energy of a workpiece.
2. Effect of vibration aging on material properties
In the production practice, it is found that the vibration aging can not only eliminate the residual stress of the workpiece, but also the strength index of the workpiece after vibration aging. This inspires us to vibrate the workpiece to strengthen the material.
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LED wash wall lamp, as the name implies, let the light like water wash the wall, mainly used for building decoration lighting, and also used to outline the large buildings.Since LED has the characteristics of energy saving, high luminous efficiency, rich color and long life, the washing wall lamp of other light sources is gradually replaced by LED washing wall lamp in 2013.
Product size
Technical parameters
1. Main material:High - pressure cast aluminum, high - light ultra - white tempered glass, back flame retardant ABS;
2. Surface treatment:UV Polyester powder coating;
3. The light body color:Dark grey;
4. Safeguard procedures:Silica gel ring compacted waterproof;
5. Average lifetime:350mA20000hours,500mA15000hours;
6. Control mode:CC/DMX512;
7. Operating ambient temperature:-25℃~50℃
8. The light colored temperature: Red/Green/Yellow/Amber/Vermilion/Acid blue/3000K/4000K/5000K/6000K
9. Light distribution device:Optical lens series:8°/15°/25°/45°/10×30°/10×60°/20×40°
10. Working voltage:DC24V
11. Way to install:Single U/Double U Adjustable Angle bracket
12. Level of protection:IP65
13. Working environment humidity:10%~90%
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