Artificial automatic soldering machine for solder main process technology is difficult to achieve, particularly in the rear section of SMT soldering process of soldering electronic components to a temperature-sensitive, heat-sensitive and can not be met due to the DIP reflow machine components, small package PITCH Components, connectors ( CONNECTOR ), cable, small CABLE , speaker and motor, etc.
Solder material as the solder connecting all three levels: connecting material of the die (die), the package (package) and a circuit board assembly. Solder can be used in a variety of physical forms, including tin bars, tin ingots, tin wires, tin powder, pre-formed ingots, solder balls and columns, solder paste, and molten state. The inherent properties of solder materials can be considered in three ways: physical, metallurgical and mechanical.
It is recognized that the reliability of solder joints depends not only on the inherent characteristics, but also on the design, the components and plates to be assembled, the process used to form the solder joints, and the environment in which it is used for a long time. Also, the characteristics of the solder joints are different from those of bulk solder materials. Therefore, the mechanical and temperature characteristics between some established bulk solders and solder joints may not be exactly the same.
Component and board design can also have a significant impact on solder spot characteristics. For example, the design of a solder mask associated with a pad ( such as a defined or unrestricted solder mask ) will affect solder spot performance and failure mechanisms. For each type of component package, observe and define the individual solder joint failure modes.
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A large number of heterogeneous crystal cores are created during curing, as well as changes in the concentration of elements or metallurgical components as the solder spots are formed. In either case, the structure may result in a lack of uniformity in the reaction. As the thickness of the solder spot decreases, this interface fading will be more pronounced. Therefore, the characteristics of the solder joint may change, and the failure mechanism may be different from that obtained from bulk solder.
The above information is provided by Miss Dongguan Key Electronic Factory 0769-89789627 
Automatic soldering machine - analysis of soldering technology