The preparation of
flux-cored tin wire is relatively complicated, and the process control is strict, including: smelting, casting, extrusion, rough drawing, fine drawing and wire winding and other processes. How to ensure the uniformity of the flux in the tin wire and avoid broken rosin defects is the whole The most critical process in the tin wire process.
Consider the following factors when selecting flux cored wire:
1. The thickness of the flux core tin wire diameter
The thickness of the flux core tin wire should be selected according to the size of the component and the welding process. If it is drag soldering, you can't choose too thin, about 0.6mm will be more suitable, if it is too thin, it will be difficult to enter tin, and you need to push a lot. If you are soldering SMD resistors, capacitors or soldering IC feet, you can choose thinner ones, 0.3mm-0.5mm.
2. Solderability of tin wire
For leaded tin wire, the process is quite mature and the choice is relatively simple. For lead-free tin wire, it must be strictly selected according to its product size, structure and application environment characteristics. If the requirements are not strict, Sn0.7Cu can be selected; if the reliability and solderability requirements are high, Sn0. 3Ag0.7Cu.
3. Solder joint reliability
The mechanical properties of flux-cored tin wires with different compositions are quite different, which also determines that the corresponding products that can meet the use requirements of the products should be selected according to the use characteristics of the products. For example, the reliability of the solder joints after soldering with lead-free tin wire is relatively poor at high temperature, but the reliability is better below 200 °C; for general household appliances and other products, the temperature below 200 °C is enough, but for many products that need to be carried out Reworked products must withstand high temperatures above 200°C.
Flux cored tin wire is widely used in electronics, electrical appliances, refrigeration, automobiles and many other fields. It is an essential key product to ensure product quality. one.
