Relatively speaking, most people are not unfamiliar with this. In my daily life, many electronic products have circuit boards and wiring boards inside. As we all know, the electronic products we use daily are densely covered with various electronic components. But how are these electronic components assembledPCBWhat about on the board? Circuit boards are no strangers to everyonesmtIn the surface mount technology (SMT) process, to ensure that the solder paste is coated on a specific pad, a steel plate corresponding to the position of the pad needs to be made and installed on the solder paste printer to guarantee that the mesh of the steel plate is in harmony withPCBThe pad positions on it are the same. After the positioning is completed, make the squeegee on the solder paste printer move back and forth on the steel mesh. The solder paste passes through the mesh holes on the steel plate and coversPCBIf solder paste printing is completed on a specific pad, how can we determine the standard of solder paste printing? The following solder paste manufacturer will explain it to you:

The criteria for judging the quality of solder paste printing:

1The position for solder paste printing.

2The printing quantity of solder paste.

The above two are the standards for testing the quality of solder paste printing. Poor solder paste printing often leads toPCBInsufficient tin, excessive tin, and sticky tin, when these conditions occur, often lead to short circuits and empty solders in the solder.

Factors affecting the quality of solder paste printing:

1Type of squeegee: For solder paste printing, select the appropriate squeegee based on the characteristics of the different solder paste or red glue. Currently, most mainstream squeegee are made of stainless steel.

2The Angle of the squeegee: The Angle at which the squeegee applies solder paste is generally45-60Between degrees.

3Squeegee pressure: The pressure of the squeegee affects the amount of solder paste. The greater the squeegee pressure, the less solder paste will be produced. This is because high pressure compresses the gap between the steel plate and the circuit board.

4The speed of the scraper: The speed of the scraper affects the shape and amount of solder paste printed, and also directly influences the quality of the solder. Generally, the speed of the scraper is set at20-80mm/sIn principle, the speed of the squeegee must be matched with the viscosity of the solder paste. The better the fluidity of the solder paste, the faster the squeegee speed should be; otherwise, it is prone to seepage.

5The demolding speed of the steel plate: If the demolding speed is too fast, it is easy to cause the solder paste to be stretched or pointed. Whether to use a vacuum seat: The vacuum seat can help the circuit board be smoothly and flat in the fixed position, and strengthen the steel platepcbThe tightness of the circuit board.

6Whether the circuit board is deformed: A deformed circuit board will cause the solder paste to be printed unevenly, and in most cases, it will cause a short circuit.

7Steel plate perforation: The perforation of steel plates directly affects the quality of solder paste printing.

8Steel plate cleaning: Whether the steel plate is clean or not is related to the quality of solder paste printing, especially the steel plate andpcbAvoid residual solder paste from underground on the circuit board contact surface to prevent it from getting onpcbThere should be no place for solder paste on it. GenerallysmtAfter a few boards are produced, the surface mount technology (SMT) factory uses test paper to clean the bottom of the steel plate. Some printers are designed with an automatic wiping function, and it is also specified how often the steel plate should be taken off and cleaned with a solvent. The purpose is to remove the solder paste remaining in the holes of the steel plate.

Generally, to solve a problem, one should first analyze where the source of the problem lies, and then think of ways to solve it. In this way, the quality of the product will not be delayed. Learn moreSolder pasteIn this regard, inquiries from others are welcome.