3. Mechanical processing problems
Significance of the present meaning: the processing quality of punching, shearing and drilling is not different, the separation force of the coating is poor or the coating is uneven in the metallized holes. Inspection method: check the incoming materials, experiment with various key machining operations, and stop the routine analysis after passing the incoming materials of the laminate through the hole metallization process.Possible reasons:
1. Data curing, resin content, or plasticizer modification will affect the drilling, punching and shearing quality of the data.
2. Poor drilling, punching or shearing processes make the consumption quality poor or inconsistent.
3. The preheating cycle time before punching or drilling is too long, which sometimes affects the processing of the laminate.
4. The aging of the data is mainly phenolic data, sometimes causing the plasticizer in the data to run away, making the data more brittle than usual.Treatment methods:
1. Contact the manufacturer of the laminate to establish an experiment that resembles the key mechanical processing performance request. Consumer molds should not be used for experiments, otherwise the wear and changes of consumer molds will affect the experimental results. In any problem of changes in machining performance, as long as the problem occurs at the same time as the batch change of the data, it is suspected that there is a problem with the quality of the laminate.
2. Please refer to the introduction and clarification on the manufacture of various types of laminates. Contact the laminate manufacturer to find out the specific drilling speed, feed, bit and punch temperature for each grade of laminate. Remember: each manufacturer uses a mixture of different resins and substrates, and its recommendation will vary.3. Preheat the laminate carefully, be sure to find any overheating areas, such as under the heating lamp. When heating data, the first-in first-out criterion should be strictly observed.
4. Check with the laminate manufacturer to obtain the aging characteristic data of the data. Turnover inventory, so that inventory is usually heavy production of plates. Be sure to detect possible overheating during warehouse storage.4. Warpage and distortion
Present meaning sign: Whether before, after or during processing, the substrate is warped or twisted. Hole tilt after soldering is also a sign of substrate warpage and distortion.Inspection method: With floating welding experiment, it is possible to stop incoming inspection. The 45-degree tilt soldering experiment is particularly effective.
Possible reasons:1. During receipt or after sawing and cutting, the material is warped or twisted, which is usually caused by improper lamination, improper cutting or unbalanced laminate structure.
2. Warpage can also be caused by improper storage of data, especially paper-based laminates, which can bow or deform when placed upright.3. Warpage is caused by the unequal coverage of the copper wall and iron wall foil. If it is 1 ounce on one side and 2 ounces on the other: the plating layer is not equal, or the special printed board design causes copper stress or thermal stress.
4 The fixture may be improperly fixed during soldering, and heavy components may cause warpage during soldering operations.5. During the process or soldering process, the hole displacement or tilt on the data is caused by improper curing of the laminate or the stress of the glass cloth structure of the substrate.
Treatment methods:1. Straighten the data or release the stress in the oven, and stop the cutting operation according to the tilt angle recommended by the laminate manufacturer and the heating temperature of the plate. Contact the laminate manufacturer to ensure that unbalanced substrates are not used.
2. Store the information flat in the loading cardboard box or lay it down on the shelf. Generally, the data should be placed at an angle of 60 degrees or less from the air.
3. Contact the laminate manufacturer to prevent unequal copper foils on both sides. Analyze the plating layer and stress, or the partial stress caused by heavy components or a large copper foil area. Redesign the printed board to make the area of components and copper balanced. Sometimes, most of the wires on one side of the printed board and the wires on the other side are laid vertically, so that the heat shrinkage of the two sides is unequal and causes distortion. It is only necessary to prevent such wiring.
4. In the soldering operation, the printed board, especially the paper-based printed board must be clamped with a clamp. In some cases, heavy components must be balanced with special fixtures or fixtures.
5. Liaise with the laminate manufacturer and use any recommended post-curing measures. In some cases, laminate manufacturers will recommend another laminate for more severe or special uses.