The world is faced with a rapidly increasing demand for bone implants. The reasons are expanding and the ageing of the world population and, consequently, an increased number of incidents such as trauma, bone tumours, skeletal deformations and other bone defects that will not heal without surgical intervention. The successful treatment of bone defects remains one of the most important challenges not only of orthopaedic surgery but also or especially of materials science searching for ideal bone substituting materials. Biodegradable metallic materials are bioactive materials with a temporary support function, which then gradually degrade without a negative effect on the organism. Versatile biodegradable metals for short-term medical implants have been intensively studied in recent years. There are three main groups of metallic biodegradable materials, Mg-, Zn- and Fe-based alloys, but each of them has at least one important drawback. Mg-alloys degrade too fast, release an excessive amount of hydrogen gas and have poor mechanical properties. An obvious drawback of Zn-based alloys is that pure Zn has very low strength and plasticity. On the other hand, Fe-based alloys, as a third group, possess excellent mechanical properties that can make them ideal candidates for applications where long-term support is needed, e.g., stents or scaffolds for cardiovascular support. The main drawback of Fe-based alloys is their very slow degradation in vitro, and even slower in vivo.

Apart from mechanical properties, the ideal bone substitute needs to possess a complex bone-mimicking geometrical design with careful selection of pore shape, pore size and porosity. Conventional techniques such as casting, sintering, foaming, and chemical vapour deposition can neither precisely control the geometry nor achieve the appropriate level of mechanical properties. The development and the progress of additive manufacturing (AM) techniques, therefore, opens up completely new perspectives and opportunities in fabricating an ideal porous metallic biomaterial due to their ability of free-form designing.

This research will show how it is possible to produce some biodegradable metallic materials using the Laser Powder Bed Fusion (LPBF) process and successfully achieve and control the rate of degradation and, at the same time, control the microstructure and mechanical properties. The results of Fe-Mn- and Zn-Mg-based biodegradable alloy development will be presented in detail.