Topology optimization of an aluminum bicycle pedal crank using laser powder bed fusion

Abstract

This study investigates the application of topology optimization (TO) in combination with laser powder bed fusion (LPBF) to design a lightweight, high-performance bicycle pedal crank using AlSi10Mg alloy. The optimization process was carried out using Fusion 360 and nTopology, resulting in a 20% mass reduction while ensuring compliance with the ISO 14781 standards for pedal cranks. The component was characterized in terms of microstructure, surface roughness, dimensional accuracy, powder distribution, and Vickers hardness. The microstructure exhibited the characteristic melt pool patterns associated with LPBF, indicative of the manufacturing process. Surface roughness measurements showed a mean value of 23.4 μm, with dimensional analysis revealing a mean deviation of 7% from nominal dimensions. The powder distribution analysis indicated a narrow particle size distribution, contributing to consistent print quality. The component’s hardness was measured at 134 HV0.3, highlighting its promising mechanical properties. This work demonstrates the potential of TO and LPBF to produce structurally optimized, lightweight components with enhanced performance, providing valuable insights into the application of Design for Additive Manufacturing for metallic materials.

Keywords

Bike crank / AlSi10Mg / Laser powder bed fusion / Design for Additive Manufacturing / Topology optimization / Metallographic characterization / Roughness dimensional analysis / Powder characterization

Funding

This research received no external funding.

Conflict of interest

The authors declare no conflicts of interest.

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