New technology of abrasive deburring for PCB
When it comes to deburring, many people immediately associate it with washing and grinding. Washing and grinding is now the most common deburring method. It is a way of deburring by using the friction between the abrasives (nylon sand, plastic sand, resin sand and plastic sand) and the workpiece. Compared with many deburring methods, the initial investment cost is low, and the operation is simple. However, with the continuous improvement of industrial requirements, the situation of its dominance begins to decompose, and more and more new methods are applied to deburring field, such as electrochemical method, electrical thermal method, sandblasting, ultrasonic, etc.
The following is a new deburring method: chemical deburring method.
In fact, chemical deburring method has existed as early as the middle of the 20th century, but it has not been widely used in the industrial field. This is because at that time, all kinds of methods were not perfect, and there were more or less limitations in repeatability, reliability, stability, cleaning and environmental protection. Until the end of the last century, a breakthrough was made in this field It was the result of that period. The process is a kind of soaking process, and the chemical product is a kind of solution. The product can selectively achieve the effect of deburring by using the difference of substrate structure and burr through the principle of vertical reaction. Compared with the traditional chemical deburring, the process has made great progress in all aspects, especially in reliability, repeatability, stability, environmental protection and other aspects is far superior to the traditional process, the following is a brief introduction to the process performance.
First, efficient and time-saving.
Compared with the traditional process, the treatment time of this process has been greatly improved. The deburring process usually takes only a few minutes, and the shortest product only takes dozens of seconds. More specifically, it depends on the material of the product, the size of the burr and the customer's processing requirements. Another performance of high efficiency and time saving is that the process can be widely used in mass production. Due to its high reproducibility and reliability, the processed products are highly consistent in terms of precision, color and size. Especially in the dimension control, the precision can meet the micron requirements. All of these provide guarantee for its wide application in industry.
Second, improve the surface finish of products.
Using this technology to deal with burr can also improve the surface finish of the workpiece, so as to achieve the polishing effect. When the workpiece is processed in various ways, its plane has a roughness in varying degrees. When treated by this process, the index can be well reduced, because the process can selectively conduct vertical reaction on the product, so that the concave convex surface gradually approaches the flat surface.
Third, it is widely used.
Whether a product can adopt this process mainly depends on the material and processing requirements of the product, and is not affected by the processing mode and geometry. Its main materials are iron, copper, aluminum and its alloy materials. Up to now, more than 200 kinds of materials have been successfully applied, and their application fields are more extensive, especially in various machining and mechanical and electronic manufacturing fields.
Fourth, safe and reliable, environmental protection, economic, simple operation.
The technology is safe, reliable and environmental protection. The main surface of safety lies in two aspects: first, product safety, which means that the processed products have high quality assurance and will not change the mechanical properties and physical and chemical properties of products due to the process. In addition, it also includes the safety performance of the product itself, which has MSDS safety certification. Second, operation and personnel safety. The process does not require special technical personnel to operate, the operators only need to undergo simple training, and only pay attention to the general chemical reagent operation safety. When it comes to environmental protection, the product conforms to ROHS certification, which is also an important guarantee for its long-term application in Bosch.
Fifthly, it can improve the electroplating effect and phosphating amount of the product and prevent hydrogen embrittlement.
Because the product can generally improve the surface finish of the product, it is conducive to enhance the electroplating adhesion of the product, so as to improve the electroplating effect. In addition, hydrogen embrittlement can be prevented by using this process, because the closed space will not be formed by using this process, which is conducive to preventing the acid substance from staying in the interior of the workpiece during electroplating, thus preventing hydrogen element from entering into the internal material of the workpiece and causing hydrogen embrittlement.
Sixth, corrosion resistance of the product can be enhanced.
The anti rust layer can better protect the workpiece. In view of this process, some customers have done salt spray test, and the results show that the salt spray test time can be greatly prolonged if there are products treated by this process.
When is the chemical deburring process most effective
1. When the complex parts with inner hole or multi hole, multi edge and acute angle cannot be treated by conventional process
2. When small and delicate workpieces can be treated as bulk materials by chemical process, and there is no risk of surface damage
3. When the workpiece not only needs deburring, but also changes the macro geometry
4. When it is necessary to obtain a pure metal surface
5. When continuous batch production must be guaranteed
6. When the required dimensional tolerance range is very small and the accuracy must be accurately reproduced
Advantages of chemical deburring process
1. The process is reliable (simply equipped with barrel, basket, tray or hanger) for soaking
2. After chemical treatment, the quality and service life of the workpiece have been significantly improved
3. The burr removal amount of each batch of goods can be accurately controlled, and the treatment effect is uniform, so the standard parts can be processed
4. The burr of easy bending and delicate workpiece does not need mechanical treatment, and the chemical treatment method is not limited by its structure and size. It is superior to traditional deburring processes such as scraping, roller polishing or grinding, and will not damage the parts with extremely sensitive surface. It is extremely difficult to remove the burr in the inner hole (such as the inner corner Burr) which can not be removed by conventional process. Even if it can, it will cost a lot of manpower and material resources, or it will take a lot of manpower and material resources to deburr the burr piece by piece with explosion method. However, chemical process can deburring in large quantities and at one time without deformation. After treatment, the surface cleanliness of the workpiece is very high. The subsequent plating can be carried out smoothly. The surface is smooth and smooth, and the residual roughness can reach 0.1 μ M. The holes formed under the surface due to mechanical treatment and corrosion after electroplating or coating treatment do not exist in chemical deburring process. The salt spray corrosion test of the parts treated by chemical process is 85 hours longer than that of other processes
5. Hydrogen embrittlement will not occur during treatment. The solution can be stored indefinitely. Just replenish and increase the concentration
6. The treatment of the produced wastewater is simple and easy, and does not pollute the environment. About 16% can be obtained by burning
7. Chemical burr immersion process will not form crystallization or sediment, and it does not need expensive cleaning of containers and pumps, or waste treatment of crystallization precipitation
9. Compared with conventional deburring process, it can save personnel and production costs
10. Never stop production equipment.