Evaluation of Powder- and Extrusion-Based Metal Additive Manufacturing Processes for the Sustainable Fabrication of Spare Parts in Electromobility

Abstract

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.

Electrical Smoothing of the Powder Bed Surface in Laser-Based Powder Bed Fusion of Metals

“…As a consequence, this leads either to scrapped components or (in the case of minor impairments) to additional work steps such as surface reworking. Consequently, this results in increased component costs and longer throughput times, thereby restricting the economic potential of PBF-LB/M [18]. These local effects are also accompanied by either a locally reduced or increased layer thickness.…”

“…As a consequence, this leads either to scrapped components or (in the case of minor impairments) to additional work steps such as surface reworking. Consequently, this results in increased component costs and longer throughput times, thereby restricting the economic potential of PBF-LB/M [18]. Furthermore, the contact-based powder bed levelling process used by current recoating systems places high demands on the flowability of the metal powders used [19][20][21].…”