Purpose This study aims to investigate the influence of additive manufactured polymer injection moulds on the mechanical properties of moulded parts. Therefore, polymer moulds are used to inject standard specimens to compare material properties to specimens produced using a conventional aluminium tool. Design/methodology/approach PolyJet technology is used to three-dimensional (3D)-print a mould insert in Digital ABS and selective laser sintering (SLS) technology is used to 3D-print a mould insert in polyamide (PA) 3200 GF. A conventionally aluminium milled tool serves as reference. Standard specimens are produced to compare resulting mechanical properties, shrinkage behaviour and morphology. Findings The determined material characteristics of the manufactured prototypes from the additive manufactured tools show differences in terms of mechanical behaviour to those from the aluminium reference tool. The most significant differences are an up to 25 per cent lower tensile elongation and an up to 63 per cent lower elongation at break resulting in an embrittlement of the specimens produced. These differences seem to be mainly due to the different morphological structure caused by the lower thermal conductivity and greater surface roughness of the polymer tools. Research limitations/implications The determined differences in mechanical behaviour can partly be assigned to differences in surface roughness and morphological structure of the resulting parts. The exact extend of either cause, however, cannot be clearly determined. Originality/value This study provides a comparison between the part material properties from conventionally milled aluminium tools and polymer inserts manufactured via additive tooling.

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Technical and legal challenges cause the implementation of Autonomous Driving in road traffic to still be a long way off. However, the introduction of driver assistance functions enables cars’ automation for low speeds already nowadays. The concept of Autonomous Transport (AT) combines automated driving with Automated Guided Vehicle’s technology. In this paper, we assess risks that emanate from AT and show fields of action for its implementation with respect to the standards for functional safety. We set up requirements for the reliability of cars’ electric power supply, actuators and sensors. Concepts for their cost-efficient fulfillment are derived. The realization of collision avoidance and navigation without additional attachments is discussed.

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