Electromobility promises to efficiently mitigate consequences of increasing traffic volume and its accompanied greenhouse gas emissions. On an individual level, electrified bikes allow emission free electrified mobility at moderate costs, and consequently their stock has increased significantly in recent years. This simultaneously increases the demand for spare parts, which are often manufacturer- or application-specific, and due to many variants, challenging to provide for the market. This article evaluates powder-based and extrusion-based metal additive manufacturing of a typical electrified bike component. The overarching objective is to establish a sustainable spare parts supply in the field of electromobility by manufacturing spare parts in a resource-efficient and decentralized manner. This approach aims to eliminate the need for physical storage space and long transport routes for the provision of spare parts, while significantly increasing the service life of e-bikes. The investigation demonstrates how these parts can be additively manufactured function equivalent and with sufficient mechanical properties, also taking economical aspects into account. Furthermore, the needed resources and related environmental consequences for metal-based additive manufacturing spare-part production are compared for both process routes. The results show that both routes are capable of producing spare-parts at comparatively the same mechanical performance, with the mechanical performance of the initial part clearly surpassed. Furthermore, it can be observed that both routes exhibit comparable resource costs, with the powder bed fusion of metals using laser beams showing significantly lower energy and gas costs by more than ten times, but higher material costs that are approximately twice as high as those of atomic diffusion additive manufacturing. Therefore, additive manufacturing offers a promising opportunity to rapidly produce parts in small quantities which are resource efficient.

Electromobility promises to efficiently mitigate consequences of increasing traffic volume and its accompanied greenhouse gas emissions. On an individual level, electrified bikes allow emission free electrified mobility at moderate costs and consequently their stock has increased significantly in recent years. This simultaneously increases the demand for spare parts, which are often manufacturer or application-specific, and due to many variants, challenging to provide for the market. This article evaluates powder-based and extrusion-based metal additive manufacturing of a typical electrified bike component to demonstrate an alternative spare parts supply. The investigation demonstrates how these parts can be additively manufactured function equivalent and with sufficient mechanical properties, also taking economical aspects into account. Furthermore, the needed resources and related environmental consequences for metal-based additive manufacturing spare-part production are compared for both process routes. The results show that both routes are capable of producing spare-parts at comparatively same mechanical performance and resource costs, while needed resources such as energy, gases and manufacturing time are significantly lower for powder-based, respectively machine costs for extrusion-based additive manufacturing. Therefore, additive manufacturing offers a promising opportunity to produce parts in small quantities resource efficient and rapidly.

Der hohe lokale Energieeintrag beim pulverbettbasierten Schmelzen mittels Laserstrahl (laser powder bed fusion, LPBF) bewirkt hohe Temperaturgradienten. Dies führt zu thermisch induzierten Eigenspannungen und Verzug in den gefertigten Bauteilen, wodurch deren Form- und Maßhaltigkeit negativ beeinträchtigt wird. In diesem Beitrag wird der Einfluss der Bauteilgeometrie und einer der Fertigung nachgelagerten Wärmebehandlung auf den Verzug von mittels LPBF gefertigten Bauteilen aus dem Werkstoff TiAl6V4 untersucht. A high local energy input during laser powder bed fusion (LPBF) creates high temperature gradients. This leads to thermally induced residual stresses and distortion, which negatively affect the dimensional accuracy of components. This paperinvestigates the influence of component geometry and heat treatment after the manufacturing process on the distortion of components made by LPBF of TiAl6V4.

Achieving a homogeneous and uniform powder bed surface as well as a defined, uniform layer thickness is crucial for achieving reproducible component properties that meet requirements when powder bed fusion of metals with a laser beam. The existing recoating processes cause wear of the recoater blade due to protruded, melted obstacles, which affects the powder bed surface quality locally. Impairments to the powder bed surface quality have a negative effect on the resulting component properties such as surface quality and relative density. This can lead either to scrapped components or to additional work steps such as surface reworking. In this work, an electric smoother is presented with which a wear-free and contactless smoothing of the powder bed can be realized. The achievable powder bed surface quality was analyzed using optical profilometry. It was found that the electric smoother can compensate for impairments in the powder bed surface and achieve a reproducible surface quality of the powder bed regardless of the initial extent of the impairments. Consequently, the electric smoother offers a promising opportunity to reduce the scrap rate in PBF-LB/M and to increase component quality.