The result of solder paste printing has a decisive influence on the quality of SMT production line. There are many factors affecting the quality of solder paste printing, such as the production process of the stencil, the design of the stencil opening, the flatness of the printed circuit board, the setting of the printing parameters, and the characteristics of the solder paste itself.
I. What are the conditions for high-quality solder paste?
1. Tin powder and flux are not separated.
2. Solder residue should have good solubility and cleanliness.
3. During the quality assurance period, the viscosity does not change much with time. Powdered tin and flux do not separate at room temperature, they should always be homogeneous.
4. the flux should be of good standard specification and non-toxic to corrosion resistance and air insulation.
5. integrated circuit parts and loop conductors should have good solderability, good adhesion and no excessive slippage when heated up.
6. it should have good spreading properties better printing results and better penetration of the screen printing plate without overflowing and sticking around the plate opening. After mixing, it should maintain a certain viscosity for a long time at room temperature, that is to say, it should have good positional stability when placing IC devices.
II. How to choose a suitable solder paste?
1. Determine the needs
Enterprises should be based on the characteristics of their own products (such as type, size, temperature, manufacturing process, application scenarios, etc.) to determine as much as possible the need for solder paste to meet the requirements of what, such as the melting point of the paste, the reflow temperature and time, is the process of printing or dispensing, whether the need for cleaning, as well as on the electrical conductivity, thermal conductivity, push and pull, thermal cycling, etc., to determine the demand is the basis for choosing a suitable solder paste products.
2. Communication
When the enterprise according to the characteristics of their products roughly determine the requirements of the solder paste products, you can contact the solder paste manufacturer or supplier. Select the most suitable product among the solder paste products that can meet the requirements.
3. Judgment
Before starting the production test, should be combined with the supplier’s information, the general judgment of the supplier to provide products can meet their own requirements, to avoid wasting unnecessary time and energy.
Features of NeoDen ND2 SMT solder paste printer
1. Advanced up/down visual system, independent controllable and adjusted lighting, high speed mobile camera lens, precisely alignment for the PCB and template and make sure that the printing accuracy is ±0.025mm.
2. High accurate servo motor and PC control which can insure the stability and precision of the printing. Unlimited image pattern recognition technology has the repeated positioning accuracy for ±0.01mm.
3. Suspended printing head which is designed specially in high rigid structure. The computer controls the pressure, speed and movement of the scraper, which can maintain the even and stability of the printing. The structure of scraper beam has been optimized designed. The scraper beam is light and well-formed.
4. The bottom of the board can be cleaned by manual or automatically. The clean function for the bottom of board is automatic and without assists. It can be programmed to control the dry, wet or vacuum cleaning. The cleaning time interval can be free to choose. It can clean all the solder paste inside the boar holes and insure the printing quality.
Post time: Nov-04-2024