In recent years, with a large number of electronic products growing in the direction of small, light and high density, especially the large number of applications of handheld devices, the original reflow surface mounting technology has been a serious challenge to the original reflow surface mounting technology in the component material technology category, which has made the reflow welding surface mount technology a rapid development opportunity.
According to technical classification
Heat plate conduction reflow welding: this kind of reflow furnace is used to heat the components on the substrate by heat conduction by heating the conveyor belt and the heat source under the push plate. It is used to select the single side of the thick film circuit of the ceramic (Al2O3) substrate. Only the ceramic substrate is attached to the conveyor belt to get enough heat. The structure is simple and the price is sold. Cheap。
IR reflow furnace: most of this reflow furnace is a conveyor belt type, but the conveyor belt only supports and transfers the utility of the substrate. The heating method is mainly heated by infrared heat source. The temperature in the furnace is more uniform than the previous method, and the mesh is very large. It is suitable for the reflow welding of the double faced substrate. Heat. This reflow oven can be considered as the basic type of reflow oven. It is applied more in China, and the selling price is also cheaper.
Hot air reflow welding: hot air flow reflow furnace uses hot air laminar flow to conduct heat energy, and through the heater and fan, the furnace air is gradually heated and circulate, and the welding parts are heated by hot gas in the furnace, and then the welding connection is completed. The hot air reflow furnace has the characteristics of uniform heating and constant temperature. The reflow furnace with full hot air forced convection has been gradually improved and perfected, as the main process of welding connection for surface mounting.
Infrared and hot air reflow welding: effectively integrated into the advantages of infrared reflow and forced convection hot air reflow welding, through the characteristics of strong penetration of infrared radiation, high thermal efficiency, power saving, and effectively overcome the temperature difference and shielding effect of infrared reflow welding, complement the hot air reflow welding to the gas flow speed demand too fast and guide The effect.
Hot wire reflow welding: hot wire reflow welding is a welding process of direct contact welding between metal and ceramic. It is usually used in cable connection of flexible substrate and rigid base plate. This heating method usually does not choose solder paste. It mainly selects tin or anisotropic conductive adhesive, and requires special welding nozzle, so the welding speed is necessary. The degree is slow and the production efficiency is low.
Hot gas reflow welding: hot gas reflow welding refers to the use of air or nitrogen in a special heating head to expand welding through hot gas flow. This method requires different sizes of welding points for different sizes of nozzles, which are slow in speed and are used for rework and development.
Laser reflow welding, beam reflow welding: laser reflow is characterized by good direction and high power density by laser beam. The laser beam is concentrated in a small area by optical system. In a very short time, a local heating area is formed at the heating place. The common laser has two types of C02 and YAG. The heating of laser heating reflow soldering is highly localized. It does not generate thermal stress and has little thermal impact. Re Minyuan components are not easy to damage.
Induction reflow welding: induction reflow welding equipment is used in the heating head to select the transformer, through the inductor eddy current process to weld the welding parts, this kind of welding method is not in contact with the machine, and the heating rate is fast; the polyinfrared reflow welding is suitable for the rework workstation, and the rework and local welding are implemented.