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Numerous metals can be processed using the additive manufacturing process laser-based powder bed fusion of metals (PBF-LB/M, ISO/ASTM 52900). The main advantages of additive manufacturing technologies are the high degree of design freedom and the cost-effective implementation of lightweight structures. This could be profitable for gears with increased power density, combining reduced mass with considerable material strength. Current research on additively manufactured gears is focused on developing lightweight structures but is seldom accompanied by simulations and even less by mechanical testing. There has been very little research into the mechanical and material properties of additively manufactured gears. The purpose of this study is to investigate the behavior of lightweight structures in additively manufactured gears under static loads.

This research identifies the static load-carrying capacity of helical gears with different lightweight structures produced by PBF-LB/M with the case hardening steel 16MnCr5. A static gear loading test rig with a maximum torque at the pinion of T₁ = 1200 Nm is used. Further focus is set on analyzing material properties such as the relative density, microstructure, hardness depth profile and chemical composition.

All additively manufactured gear variants show no failure or plastic deformation at the maximum test load. The shaft hub connection, the lightweight hub designs and the gearing itself are stable and intact regarding their form and function. The identified material characteristics are comparable to conventionally manufactured gears (wrought and machined), but also some particularities were observed.

This research demonstrates the mechanical strength of lightweight structures in gears. Future research needs to consider the dynamic load-carrying capacity of additively manufactured gears.

This chapter provides an introduction to the world of family companies and family constitutions from a legal perspective. It first studies the legal types of business organizations that family firms have chosen across time and jurisdictions. It then illustrates how early predecessors of family constitutions evolved in the late Middle Ages and what modern family constitutions look like in different countries today. Further considerations are devoted to the governance framework of family firms. The chapter concludes by exploring the potential legal effects of family constitutions under German company and contract law.

Although resource sharing between scholars is evolving rapidly, This paper uses paper-based interlibrary lending (ILL) procedures in the service repertoire of academic libraries. However, the current business model of acquiring toll-access journals and e-books does not seem to fit very well with traditional ILL practices. In addition, the new models of peer-to-peer resource sharing between academics seem to be much more effective than ILL. Scholars arrange access to the needed publications by using legal (buying, exchanging) and illegal means (Sci-Hub, etc.). Furthermore, the demands for open access have increased, voiced not only by librarians and science funders but also by politicians. This development might change the scholarly publication ecosystem, even though older publications are still likely to remain closed.

This paper contrasts the ILL and usage statistics of Finnish university libraries with the use of ResearchGate, a popular academic social network, which we treat as an example of a peer-to-peer sharing service.

Based on the data, there seems to be a change of paradigm in the resource sharing: the traditional ILL seems to be decreasing and becoming more like a niche service and the digital use and use of social media peer-to-peer resource sharing applications seem to increase rapidly.

The paper examines current resource sharing trends. The analysis is based on the data of Finnish resource sharing, interlibrary lending and ResearchGate usage.