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Laser Powder Bed Fusion is the most widespread additive manufacturing process for metals. In literature, there are several analytical models for estimating the manufacturing cost. However, few papers present sensitivity analyses for evaluating the most relevant product and process parameters on the production cost. This paper presents a cost model elaborated from previous studies used in a sensitivity analysis. The most relevant process parameters observed in the sensitivity analysis are the 3D printer load factor, layer thickness, raw material price and laser speed.

The part build orientation is a manufacturing variable that must be considered when designing a product to maximise AM opportunities. There are several approaches to selecting the best print direction in the scientific literature by considering different criteria. However, most of the studies are focused on specific AM technologies. It is missing a general method that evaluates a widespread number of criteria. Furthermore, such approaches expect designers establish weights for technical criteria that are too specific, especially during the preliminary design steps. Designers are familiar with criteria like cost-effectiveness, productiveness, quality and mechanical strength.The paper presents a multi-criteria decision-making approach to optimise the build part orientation in additive manufacturing. The method considers five decision-making criteria (cost-effectiveness, rapidity, productiveness, quality and mechanical strength) and seventeen specific technical criteria. TOPSIS is the method used to optimise the build part orientation. A case study of three components exemplifies the five steps of the procedure.

Investment casting (IC) is a manufacturing process for making components giving an excellent surface finish, dimensional accuracy, and complex shapes. Despite these benefits, IC requires high cost and lead time for realizing the metallic mold for pattern manufacturing. To avoid the shortcoming of casting processes, Additive Manufacturing (AM) is widely used for fabricating patterns, cores, and molds (Rapid Casting - RC). Several applications concerning rapid investment casting (RIC) through Fused Filament Fabrication (FFF) and Stereolithography (SLA) were developed. However, a techno-economic analysis based on SLA application for RIC is missing. This paper presents a techno-economic analysis regarding SLA adoption for RIC. SLA is compared with wax injection, the traditional approach for realizing wax patterns. The article provides a decision-making tool that supports stakeholders in evaluating when AM is convenient (cost and lead time) for creating wax patterns, considering different production scenarios. For the compared technologies, the authors developed analytical cost models capable of assessing the cost of the entire production process and evaluating the postprocessing phases. The following characteristics were considered: (i) different production volume, (ii) machine load factor, and (iii) parts features (i.e., dimensions and shape). The results show that SLA, for small parts, is more convenient than wax injection when the production volume is higher than 1E+03.

Environmental sustainability represents an unavoidable design driver. The consciousness of the importance of tackle the topic of environmental sustainability since the first stages of the product lifecycle is slowly spreading through enterprises. However, although they reach this grade of awareness, it is hard to introduce additional considerations to the traditional drivers of functionality, manufacturability, assembly, cost, etc. Therefore, it is crucial to identify methods and tools to support companies in efficiently integrating environmental sustainability issues in their design process. This paper proposes an approach to identify the inputs, functionality and outputs suitable to each industrial reality. Its core is the eco-design tool matrix, that estimates the tool implementation time and suggests proper outputs; from this the necessary inputs and functional blocks are derived. The approach is applied to the cases of two Italian industries, very different one another. This proves the wide applicability of the approach. The definition of a validation procedure represents the next steps to identify the benefits of the approach.