PSI - Issue 41

A.R.F. Soares et al. / Procedia Structural Integrity 41 (2022) 48–59 Soares et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 4. Numerical model for the simulations: imposed load and boundary conditions (a) and meshed model with loads (b).

Fig. 5. von Mises stresses at the design load.

3.3. Fabrication Once the design was validated through the FEM analyses, it was fabricated in house, noting that only non standard or non-commercially available parts were manufactured. 3.3.1. Acquired components The linkages are interconnected using pins, which were acquired from a commercial supplier. The chosen pins possess a release mechanism that locks them in place. Furthermore, as supplied, they come with the desired tolerances and finish. In addition, all the fasteners, the LVDT (DCTH1000A) sensors, and all the raw materials from machining were acquired from local suppliers. The selected fasteners were ISO 4762 and ISO 4034 with different sizes. 3.3.2. Component fabrication From the geometry shown in Fig. 1, it can be observed that most of the components are non-standard, and most of these components are prismatic. Therefore, these components were machined from bars and plates of tool steel (40CrMnNiMo8-6-4). The pins that hold the specimen to the device (links 8 and 9 in Fig. 1) were standard parts acquired. However, their heads were machined to provide a flat surface that contact the LVDTs. Similarly, the threaded rods used for supporting the beams and the LVDTs had a few features machined. In this work, the part models were imported into Fusion 360 (Autodesk Inc, USA), which allowed creating the G-code for machining. Although the G-code provided by the software is mostly ready to use, it was reviewed before machining each part. The machining took place in-house using a computer numeric control (CNC) machining centre, whilst the round