Laser powder bed fusion (L-PBF) of metals enables the manufacturing of highly complex geometries which opens new application fields in the medical sector, especially with regard to personalized implants. In comparison to conventional manufacturing techniques, L-PBF causes different microstructures, and thus, new challenges arise. The main objective of this work is to investigate the influence of different manufacturing parameters of the L-PBF process on the microstructure, process-induced porosity, as well as corrosion fatigue properties of the magnesium alloy WE43 and as a reference on the titanium alloy Ti-6Al-4V. In particular, the investigated magnesium alloy WE43 showed a strong process parameter dependence in terms of porosity (size and distribution), microstructure, corrosion rates, and corrosion fatigue properties. Cyclic tests with increased test duration caused an especially high decrease in fatigue strength for magnesium alloy WE43. It can be demonstrated that, due to high process-induced surface roughness, which supports locally intensified corrosion, multiple crack initiation sites are present, which is one of the main reasons for the drastic decrease in fatigue strength.

Additive manufacturing (AM) has become increasingly important over the last decade and the quality of the products generated with AM technology has strongly improved. The most common metals that are processed by AM techniques are steel, titanium (Ti) or aluminum (Al) alloys. However, the proportion of magnesium (Mg) in AM is still negligible, possibly due to the poor processability of Mg in comparison to other metals. Mg parts are usually produced by various casting processes and the experiences in additive manufacturing of Mg are still limited. To address this issue, a parameter screening was conducted in the present study with experiments designed to find the most influential process parameters. In a second step, these parameters were optimized in order to fabricate parts with the highest relative density. This experiment led to processing parameters with which specimens with relative densities above 99.9% could be created. These high-density specimens were then utilized in the fabrication of test pieces with several different geometries, in order to compare the material properties resulting from both the casting process and the powder bed fusion (PBF-LB) process. In this comparison, the compositions of the occurring phases and the alloys’ microstructures as well as the mechanical properties were investigated. Typically, the microstructure of metal parts, produced by PBF-LB, consisted of much finer grains compared to as-cast parts. Consequently, the strength of Mg parts generated by PBF-LB could be further increased.

Present-day thermode bond systems for the assembly of radio-frequency identification (RFID) chips are mechanically inflexible, difficult to control, and will not meet future manufacturing challenges sufficiently. Chip bonding, one of the key processes in the production of integrated circuits (ICs), has a high potential for optimization with respect to process duration and process flexibility. For this purpose, the technologies used, so far, are supposed to be replaced by a transmission laser-bonding process using low-melting eutectic alloys. In this study, successful bonding investigations of mock silicon chips and of RFID chips on flexible polymer substrates are presented using the low-melting eutectic alloy, 52In48Sn, and a laser with a wavelength of 2 μm.