In the entire production process of the previous electronics industry, the traditional welding process often has shortcomings such as many residual residues, high corrosion, and poor appearance. After welding, it is necessary to use plate washing water to clean, and there will be fine gaps during cleaning. , The cleaning difficulty brought about by the assembly of high-density components increases the cleaning cost and wastes man-hours! So a new type of "no-clean" tin wire
appeared for the needs of the development of the electronics industry.
Although many people are using no-clean tin wire now, there are still many people who don't know what "no-clean" means?
The so-called "no-clean" refers to the use of low-solid, non-corrosive flux in the production of electronic assemblies, and soldering in an inert gas environment. The residue on the circuit board after soldering is extremely small, non-corrosive, and has Extremely high surface insulation resistance, under normal circumstances, it can reach the standard of ion cleanliness without cleaning, and can directly enter the process technology of the next process.
It must be pointed out that "no cleaning" and "no cleaning" are absolutely different concepts. The so-called "no cleaning" refers to the use of traditional rosin flux or organic acid flux in electronic assembly production. There is a certain residue left on the surface of the solder strip, but it can meet the quality requirements of some products without cleaning, such as household electronic products, professional audio and video equipment, low-cost office equipment and other products, which are usually "not cleaned" during production. Yes, but definitely not "no clean".
1- Consider the performance and working conditions of welded components:
For weldments that need to withstand impact loads, in addition to meeting the strength requirements when selecting solder bars, we should also try our best to ensure that the metal weld has a relatively high impact toughness and plasticity. Therefore, when we choose, we should choose some low-hydrogen solder bars with relatively high toughness indicators of plastic lead-free tin wires. When we need to weld corrosive media, we should choose according to the nature of the medium and the characteristics of corrosion. We can choose stainless steel type solder bars or other corrosion-resistant solder bars; if the weldment is performed at low temperature or other special conditions If it is used, then we should choose solder bars for low temperature steel, surfacing or other purposes.
2. Consider the chemical composition and mechanical properties of the weldment:
If the ordinary structural steel is welded, then we should require the strength of the weld metal and the base metal to be at the same height; if the lead-free tin bar is welded with alloy structural steel, the solder with a similar alloy composition and base metal should be selected. strip;
3. Consideration of construction conditions and economic benefits:
When choosing solder bars, we should choose acid solder bars with better process performance as far as possible while meeting the requirements of performance. If the weldment is used in poor ventilation conditions or in a narrow space, acid-resistant or dust-proof solder bars should be selected; if the welding work is relatively large, high efficiency can be selected within the allowable range The solder bar is used to improve the production efficiency of welding.