Time

16.12.2022 kl. 10.00 - 13.00

Abstract:

Short series production of parts that needs to be manufactured by injection molding remains a challenge for many manufacturing companies. In this study, alternative short-series manufacturing technologies such as direct additive manufacturing (DAM) and indirect additive manufacturing (IAM) technologies for low volume injection molded parts have been reviewed.

Our review and further analysis show that 3D-printed tooling, such as e.g. Freeform Injection Molding (FIM) which is an IAM technique, can combine the benefits of traditional injection molding (IM) such as scalability and material versatility with benefits of DAM such as design freedom, low start-up costs and short lead-times to address some of the challenges seen in production of low-volume injection molded parts.

The purpose of this study is 1) to develop a methodology, which can enable industrial end-users to identify most suitable parts from part libraries to be manufactured by FIM, 2) to develop a framework for adoption of FIM to better understand the procedures and challenges related to the FIM implementation process 3) to develop a framework to build ware housing of part portfolios to produce the parts on-demand and build resilience into supply chain.

Without an efficient part identification methodology, it will be very difficult and, in some cases, impossible to make a short list of components that may be successfully made using FIM. Several methodologies exist for part selection for additive manufacturing (AM). However, as the technical and economical parameters for part selection for AM are not applicable for part selection for FIM, this study fills the gaps in the literature regarding the lack of any tool for part selection for FIM and also how using FIM reference parts influences the result of part selection. Our proposed comprehensive methodology can be used ‘without’ and ‘with’ FIM reference parts. In the reference part-based method, the part identification process starts by finding the similar parts, from the case company part portfolio to some FIM reference geometries.

This will be followed by clustering the parts based on their size. Then a multi-criteria decision-making (MCDM) approach is applied for ranking the clusters and ranking the parts within each cluster. Regardless of which approach is used, once the first set of potential candidates were identified, the cost of using FIM manufacturing is calculated to conduct cost comparison between traditional manufacturing and FIM.

Without a framework for adoption of FIM, it will be very difficult for the companies to consider the internal and external factors influencing the implementation process and investigate the FIM potential benefits against the costs of change.

Our analysis shows that the concept of virtual warehousing (VW) provides a useful framework to address some of the challenges with traditional warehouses such as high inventory costs, difficulties in forecasting the customers demand and delivering the parts to the customer on time.

The novelty of the research presented here lies in: a) development of a systematic methodology for part selection for a novel manufacturing paradigm (FIM), b) comparison of the suitability of a non-reference part-based approach with reference part-based approach for identifying the most suitable part candidates for FIM, c) proposing a multi-steps process for implementing FIM and d) introducing a framework for building virtual warehouse considering external and internal factors.

Assessment Committee:       

• Associate Professor Yang Cheng (chair), Department of Materials and Production, Aalborg University
• Associate Professor Mélanie Despeisse, Chalmers University of Technology
• Director, PhD Jeppe Skinnerup Byskov, Danish Technological Institute

Supervisor:

• Associate professor Atanu Chaudhuri, Department of Materials and Production, Aalborg University

Co-supervisors:

• Professor Brian Vejrum Wæhrens, Department of Materials and Production, Aalborg University

Industrial supervisor:

• Lasse Guldborg Staal, CEO of AddiFab ApS

The PhD defense will be hosted by moderator Rikke Vestergaard Matthiesen.

The lecture constitutes a 45 minutes presentation by Elham Sharifi followed by a short break and a discussion session with questions from the opponents and the auditorium.