*4.2.1 Dimensional analysis*

During the casting operation, a core shifting may occur, which could alter the dimensional correctness of the disc swan neck thickness. Therefore, inspecting the correctness of this thickness is sometimes crucial to avoid a reduction in load-bearing capacity. A core is a pre-determined shape of the mold, which provides internal cavities, recesses, or projections in the casting. The tendency for core instability during the casting operations is high due to pressure build-up or operational error during the mold filling. A core shift is a defect due to the buoyancy of liquid metal that causes the core of the cast to move from its correct position. If a core shift occurs, it causes a dimensional inconsistency in the casting. **Figure 5** shows a schematic illustration of the brake rotor suggesting the design requirement of the rotor swan neck thickness. As indicated in the figure, the specified thickness is 6.5 ± 0.25 mm. The failed disc swan neck thickness was determined as 6.62 ± 0.02 mm, which is still within the design specifications. This analysis suggests that the failure was not caused by core shifting.
