Detailed solutions and comprehensive know-how play a central role for the production processes in the electronics industry, which are subject to continuous change. An example: In order to cover the SMD components and solder the THT components – despite ever smaller distances between the components – Leutz Lötsysteme works, among other things, with titanium covers or narrow titanium bars in a solder mask (Fig. 1).
This is because the high packing density of the SMD components on the PCB makes it increasingly difficult to apply heat. Currently, 80 to 90 % of the PCB is covered and through 10 to 20 % open soldering windows the preheating can bring the heat into the PCB. Due to the small openings of the solder mask, strong temperature differences occur in the PCB, which result in equally strong voltages.
The titanium plate immediately transfers the heat of the preheating to the circuit board when solder is applied. Due to the optimal preheating of the circuit board, a solder penetration of up to 100 % and a very even heat distribution in the circuit board ( ± 5 °C) is achieved. When processing and using titanium, however, a number of points need to be taken into account - these include the material properties of titanium, for example:
"We offer the right titanium for each application and pay attention to the tensile strength, thermal conductivity and thermal expansion of the material, among other things", points out Nicole Leutz, authorized signatory, Leutz Lötsysteme GmbH, who is responsible for the project-specific fine tuning.
A further advantage of using titanium inserts or complete titanium carriers (Fig. 2) is the accuracy. In the meantime, dimensions of 0.01mm and - depending on the size of the carrier - a flatness of 0.1mm are achieved. This detailed solution shows how reproducibility and constant processes can be realized with the individually suitable equipment. But suitable equipment is not only a result of modern production technology.
"Therefore, we react to ever tighter customer deadlines and smaller batch sizes with a highly flexible production organization, because effective electronics production can only be achieved by taking a holistic view of all relevant aspects. And this then minimizes the degree of the respective project challenge."
- Circuit board