The purpose of the present work is to study the effect of workpiece volume on reducing the shell wall thickness in rapid shell casting based upon three-dimensional printingud(3DP) technology, and to evaluate the dimensional accuracy and mechanical properties of aluminum (Al) castings obtained as per the ISO standard UNIEN 20286-I (1995). Starting from the identification of component/benchmark, castings of different volumes (corresponding to workpieces of ɸ60 mm, ɸ50 mm and ɸ40 mm) were produced with different shell wall thicknesses. Measurements on a coordinate measuring machine (CMM) allowed the calculation of the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The research proved that having a shell wall thickness with a value lessudthan that recommended (12 mm) is more suitable from a dimensional accuracy and economic point of view (irrespective of the workpiece volume within the given selected range). All the castings produced with different shell thicknesses are acceptable as per the ISO standard. The results of the study suggest that workpiece volume has an unnoticeable effect on reducing the shell wall thickness for the selected range of volumes of casting. Furthermore, the hardness of castings produced is almost same forudall shell wall thicknesses, from 12 mm to 1 mm. The results are supported by cooling (time-temperature) curves, which show unnoticeable changes in the rate of heat transferudat different shell wall thicknesses. Keeping in mind the cost effectiveness of the process, one (1) mm shell wall thickness has been recommended for the production of castings. For a 1 mm shell wall thickness, the production cost and time are reduced by 67.38% and 44.87% (for ɸ60 mm workpieces), 64.51% and 44.62% (for ɸ50 mm workpieces), and 69.50% and 59.64% (for ɸ40 mm workpieces), respectively. ud
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机译：本工作的目的是研究基于三维印刷 ud（3DP）技术的工件体积对快速铸造薄壳时减小壳壁厚度的影响，并评估铝（Al）的尺寸精度和力学性能。 ）铸件是根据ISO标准UNIEN 20286-I（1995）获得的。从识别零件/基准开始，生产了不同体积的铸件（对应于，60 mm，and50 mm和ɸ40mm的工件），并具有不同的壳壁厚度。在坐标测量机（CMM）上进行的测量可以计算出所生产铸件的尺寸公差。还比较了一些重要的机械性能，以验证铸件的适用性。研究证明，从尺寸精度和经济角度考虑（与给定选定范围内的工件体积无关），壳壁厚度小于建议值 udud（建议为12毫米）更适合。根据ISO标准，以不同的外壳厚度生产的所有铸件都是可以接受的。研究结果表明，在选定的铸件体积范围内，工件体积在减小壳壁厚度方面没有显着影响。此外，对于总的壳壁厚度，从12毫米到1毫米，所生产铸件的硬度几乎相同。结果得到冷却（时间-温度）曲线的支持，该曲线显示了传热速率的显着变化不同的壳壁厚度。考虑到该工艺的成本效益，建议在生产铸件时使用一（1）毫米的壳壁厚度。对于1 mm的壳壁厚度，生产成本和时间分别减少67.38％和44.87％（对于ɸ60mm的工件），64.51％和44.62％（对于ɸ50mm的工件）以及69.50％和59.64％（对于ɸ40mm的工件）工件）。 ud
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