Laser reflow welding

The perfect spot welding paste system, it can according to the heating demand of different products, use of various techniques to complete the solder joint welding.And other similar heating method, the misuse of laser energy is easy to burn out parts.Laser heater take full advantage of the characteristics of transmission and absorption of laser energy, according to the properties of reflow solder paste to create an environment of reflux, this can make a very difficult task of welding can be done with extremely high rty.

Backflow test has to do with the samples is a mature method to determine the laser reflow is suitable for the product, and in order to achieve the desired quality of solder joint must be controlled by the process parameters.Theoretical analysis and study laser how to work is one thing, but the actual application is another.If on a product, the recycling of solder paste with a laser to complete is identified as a feasible method, then we can cooperate with solder paste and laser equipment system supplier, the best combination of materials and equipment of the product.

Carbon dioxide laser is currently the strongest available cw laser.Co2 laser can produce about 10600 nm wavelength infrared light and 20% of its power.CO2 laser used for metal cutting and welding.Co2 laser is made of yttrium aluminum garnet doped neodymium metal, usually called a Nd: YAG laser.Nd: YAG laser can produce high energy and wavelength of 1064 nm in the infrared spectrogram.CO2 laser and similar, they are mainly used in cutting and welding metal, also used for marking on metal and other materials.High power diode laser (HDL) mainly depend on GaAs semiconductor.Can provide a range of 790 ~ 980 nm wavelength and each of the 50 watts of power output.In the past few years, to keep the temperature of the diode as the target of diode cooling technology, significantly increased the diode power, longevity, and efficiency.

Laser reflow soldering technology

Some users choose to use the laser heating, because it is the best option in many means;And other users found that due to very limited feasible heating means, laser will be a solution to the problem when they faced by heating.Using laser heating is the most direct reason no contact the local heating of hope.Although motivation each are not identical, but the purpose is the same: reflux is limited to a certain position, not spread to other areas, and in a very short time to finish, so as to effectively avoid other parts of the product is more heat conduction.

Cable placed before solder paste is point in all the welding plate.Laser heating is after welding paste process, done in a line, and add the heat just formation of solder joints.In the molten solder time not more than 3 seconds.When the heat conduction to heat on the surface of the glass substrate is very few, can prevent the blowout of thermal expansion.While the appearance of the solder joint satisfies the requirement of consistency.The same as previous process, parts on each pin spot welding paste respectively, then separate by laser heating, each pin because of heat conduction, the first pin than fourth pin longer heating time.Local heating temperature is enough, and the total quantity of heat for plastic parts is safe