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Knowing the tolerance interval capabilities (TICs) of a manufacturing process is of prime interest, especially if specifications link the manufacturer to a customer. These TICs can be determined using the machine performance concept of ISO 22514. However, few works have applied this to Additive Manufacturing printers, while testing most of the printing area as recommended takes a very long time (nearly 1 month is common). This paper, by proposing a novel part design called COMPAQT (Component for Machine Performances Assessment in Quick Time), aims at giving the same level of printing area coverage, while keeping the manufacturing time below 24 h. The method was successfully tested on a material extrusion printer. It allowed the determination of potential and real machine tolerance interval capabilities. Independently of the feature size, those aligned with the X axis achieved lower TICs than those aligned with the Y axis, while the Z axis exhibited the best performance. The measurements specific to one part exhibited a systematic error centered around 0 mm ± 0.050 mm, while those involving two parts reached up to 0.314 mm of deviation. COMPAQT can be used in two applications: evaluating printer tolerance interval capabilities and tracking its long-term performance by incorporating it into batches of other parts.

In the Industry 4.0 era, the modelling of machining operations happens to be a crucial aspect of production sector. With adequate models, predicting the appearance of chatter and selecting optimised operational parameters is possible. For the dynamics simulation of machine tools or robots performing 5-axis operations, modelling approaches are continuously in improvement. A robust method is proposed for the cutter-workpiece engagement (CWE) computation at each step of a dynamic simulation, by determining the machining forces as well as the resulting machined surface. The CWE is estimated based on the interference between the workpiece, modelled with tri-dexel approach, and the tool, considered as a triangle-mesh surface of the swept volume. The relative closest triangle algorithm is used for a robust intersection management, suited for 5-axis trajectories. A hybrid dexel-based-analytic method is presented for accurate estimation of the uncut chip thickness. Furthermore, an approach is proposed for a simulation-based evaluation of the part resulting from dynamic simulations by comparing dexel networks with each other. It allows to assess the impact of operational parameters on parts at the simulation level. The CWE determination method proposed is validated with experimental data from force measurements and benchmark tests of different scales from macro- to micro-milling.

The conventional manufacturing chain for technical ceramics is too expensive for the production of small series or unique parts with complex designs. Hybrid machines that combine additive and subtractive processes can be an interesting solution to overcome this technology lock-in. However, despite the great interest in hybrid machines for metallic parts, there is a lack of data in the literature when it comes to ceramics. The purpose of this paper is to contribute to closing this gap. It is the first to evaluate the achievable geometrical tolerances according to ISO 2768-2 as well as the surface textures of composite zirconia parts shaped sequentially by pellet additive manufacturing (PAM, from ceramic injection molding feedstock) and finish milling. The green parts were then debinded and sintered to analyze the influence of these steps. Compared to the initial green parts, the sintered parts exhibited shiny and smooth surfaces with sharp edges. Flatness, parallelism and perpendicularity all achieved an H (fine) class, while the surface textures were significantly improved, resulting in arithmetic roughness (Ra) below 1.6 µm.