Welding is an important part of the printed circuit board design process, welding is the electronic components fixed in the printed circuit board, in the PCBA processing, wave soldering and reflow soldering are two common welding process, but different scenarios are not the same choice of welding method, what is the difference between these two welding processes?
DIP Wave Soldering:
Wave soldering is a batch PCBA welding process, is the high temperature melting liquid tin and PCB board components plug-in welding. The wave soldering process consists of four steps: flux spraying, pre-coating, wave soldering and cooling.
Flux: Primarily used to remove oxides from the board, flux provides lower surface tension, thermal transmittance and a smoother soldering process.
Preheating: The PCB passes through a thermal channel to preheat and activate the flux.
The wave soldering process consists of four steps: flux application, preheating, wave soldering and cooling.
Wave Soldering: As the temperature continues to rise, the solder paste turns to liquid and forms a wave over which the edge of the board will travel and the components can be firmly bonded to the board.
Cooling: The wave soldering profile follows the temperature profile. As the temperature peaks during the wave soldering phase, the temperature drops and is called the cooling zone.
Reflow Soldering:
Reflow soldering is the permanent bonding of components that were first temporarily adhered to pads on the board by means of a solder paste, which will be melted by conduction through hot air or other thermal radiation. Reflow soldering has four soldering processes are: preheating, holding, reflow soldering, cooling.
Preheat: Preheating conforms to the thermal profile and does a good job of removing volatile solvents that may include solder paste.
Holding: The board warms up and enters the holding area. Ensuring that any areas that are not fully heated due to the shadowing effect reach the necessary temperature, the other activates the flux and removes solder paste solvents or volatiles.
Reflow Soldering: The reflow zone is the area that reaches the highest temperature during the soldering process. Here the solder melts and forms the necessary solder joints. The actual reflow process means that the flux reduces the surface tension at the metal joint, resulting in metallurgical bonding, which causes the individual balls of solder powder to combine and melt.
Cooling: This needs to be done in such a way that there is no pressure on the components of the cooling plate after reflow. Proper cooling inhibits the formation of excess intermetallic compounds or thermal shock to the assembly.
Difference between wave soldering and reflow soldering:
In short, wave soldering is primarily used for soldering plug-in components and reflow soldering is primarily used for soldering SMD components. As far as welding is concerned, the difference between wave soldering and reflow soldering can never be ignored. Tortai, as a professional PCBA manufacturing service provider, has been focusing on providing highly reliable electronic assembly manufacturing services for 16 years, mainly focusing on the fields of medical care, new energy, automotive electronics, security, communications, AI artificial intelligence, and so on. Core technical team members have more than 10 years of experience in the electronics manufacturing industry, so far has been more than 40 countries and regions around the world more than 300 customers in different industries to provide highly reliable electronic assembly services, if you have PCBA processing services you can contact us.