Comparison of advantages and disadvantages of SMT steel mesh processing methods
Initially, the manufacturing process of SMT steel mesh was mainly to make plates by photography, and then through the use of chemical corrosion processing methods. Of course, there is also the use of laser cutting processing method or electroforming processing method to process the plate making of SMT steel mesh.In the process of continuous production and processing of SMT steel mesh, it is found that the three processing methods outlined above have their own advantages and disadvantages. The advantages and disadvantages of these three SMT steel mesh processing methods are compared below：
1. Chemical etching is the earliest processing method used in SMT steel mesh processing.
Advantages of the chemical corrosion method: chemical corrosion is used to perform leak processing on the SMT steel mesh without expensive equipment investment, and the processing cost is relatively low.
Disadvantages of the chemical corrosion method: the corrosion time is too short, the hole wall of the SMT steel mesh may have sharp corners, if the time is too long, the hole wall size may be enlarged, and the side corrosion also makes the smoothness of the hole wall not high. The accuracy that cannot be mastered is very accurate.
2. The laser processing method is currently the most commonly used SMT steel mesh processing method. It relies on laser energy to melt the metal, and then cuts an opening in the stainless steel plate.
Advantages of laser processing method: the processing speed is much faster than the chemical corrosion method, and the opening size of the steel mesh is also easy to control, especially the added hole wall is tapered (taper about 2 degrees), which is easier to remove mold.
Disadvantages of the laser processing method: When the openings of the SMT steel mesh are dense, the local high temperature generated by the laser sometimes deforms the adjacent hole walls, and the roughness of the metal exchange hole walls formed by melting is not high, so if necessary The hole wall needs to be trimmed. In addition, laser processing methods increase processing costs due to the need for dedicated equipment.
The current SMT steel mesh processing methods are all done by laser cutting, and laser cutting is made using file data, with high precision and small tolerances.
3. The electroforming method is a process that relies on the continuous accumulation and accumulation of metal materials (mainly nickel) to form a metal SMT steel mesh.
The advantages of the electroforming method: The SMT steel mesh produced by the method not only has high opening size accuracy and smooth hole walls, which is beneficial to the quantitative distribution of printed solder paste, but also the opening is not easily blocked by the solder paste, thereby reducing the number of times of cleaning the SMT steel mesh.
Disadvantages of electroforming: the cost of manufacturing SMT steel mesh by electroforming is high and the production cycle is long.
Through continuous research and practice, it has been discovered that no matter whether it is a chemical corrosion method or a laser cutting method, the SMT stencil will be blocked in different degrees during printing. The SMT stencil needs to be cleaned frequently, so the electroforming method has become a fine pin. The main processing method of SMT stencil for solder paste printing of pitch components.
