# Evaluating the Degradation of WE43 for Implant Applications: Optical and Mechanical Insights
## 5 Conclusions and Outlook  
In this work, the experimental setup for analysing the degradation behaviour was first presented. To verify the obtained and measured values, for example, the measured pH value was compared with the data from [PERSON] et al. [24] and [PERSON] et al. [27]. In addition, the appropriate positioning of the samples in the experimental chamber was also analysed. Three different positions were compared for this purpose. Based on the flow situation and the measured surface roughness, position X\({}_{2}\) is recommended for further experiments. In an abstracted form, this position best reflects the ratio of slow and uniform flow of the fluid to the subsequent implant application. Both typical forms of degradation (uniform and local degradation) could be demonstrated by optical measurement of the height differences, which were 0.02 mm for uniform degradation and up to 0.05 mm for local degradation. This once again emphasises the usability of the experimental setup. Analysis of the degradation  
Figure 15: Optical analysis results of sample geometry 2 after five days in the HBSS ((**a,b**) optical measurement; (**c**) microscope images).  
layer revealed a reduction of mechanical properties in the degradation layer. Consequently, the degradation layer does not contribute to the additional stabilisation of a potential implant. This consideration must be taken into account when designing implants made from this material.  
Overall, the results presented validate the design of the experimental chamber. Additionally, they provide an analysis of the mechanical properties of the degradation layer, facilitating the application of the WE43 alloy as an osteosynthesis implant. The next step involved conducting experiments with a constant pH value to more accurately replicate the conditions of in vivo applications. Furthermore, the influence of the choice of geometry and the manufacturing process on the application as a potential bone screw should be examined in more detail. With regard to its application as a bone screw, additional experiments should be conducted to assess a longer degradation time and to determine further mechanical properties, such as tensile strength. All these analyses can then be used as a basis for developing a numerical model to predict the degradation of magnesium alloy WE43. Thus, a realistic numerical design of implants is possible, considering the development of human bone and implant properties.  
Conceptualization, B.-A.B., H.W., A.C. and J.S.; methodology, J.S.; software, A.C. and J.S.; validation, A.C. and J.S.; formal analysis, J.S.; investigation, A.C.; resources, J.S.; data curation, A.C., J.S. and N.M.; writing--original draft preparation, J.S.; writing--review and editing, N.M. and H.W.; visualization, J.S.; supervision, B.-A.B.; project administration, J.S.; funding acquisition, B.-A.B. and H.W. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The raw data supporting the conclusions of this article will be made available by the authors on request.  
The corresponding author would like to thank [PERSON] for making this study possible.  
The authors declare no conflicts of interest.