PSI - Issue 75

Ninian Sing Kok Ho et al. / Procedia Structural Integrity 75 (2025) 35–42 Author name / Structural Integrity Procedia (2025)

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a)

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d)

Figure 2: Support structure faces after a) production focused rapid manual grinding, b) precision refined manual grinding [7], c) milling, and d) X-ray CT reconstruction of a surface processed using production focused grinding like that in a)

2.2. Fatigue Testing All samples were tested under cyclic loading under force control at R = 0.1 and 10 Hz using a Shimadzu Servopulser machine (Figure 1c). The samples were tested to failure or to 10 million cycles, at which point they are considered runouts. 2.3. X-ray Computed Tomography 1 runout sample from the production grinded batch and 2 from the precision grinded batch were scanned along the central 20 mm portion of the hourglass section using a Nikon XTH 225 ST machine. The voltage was 223 kV, the current was 44 μ A, and a 0.25 mm thick tin filter was used. There were 1600 frames in total. The resolution was 17 μm.