Supporting Method for Thin Parts Having Curved Surfaces – Improvement of End Milling Accuracy by Using Low-Melting Point Alloy and Elastomer Support –
Akinori Saito*,, Shinya Kato**, and Mitsuo Nagao*
1 Nakagawara, Tokusada, Tamura, Koriyama, Fukushima 963-8642, Japan
**Nihon System Eight Co., Ltd., Mito, Japan
Many mechanical parts have complicated and delicate shapes for improving their functionality and designability. To machine thin parts with high accuracy, it is necessary to reduce the cutting force induced on the workpiece or to clamp the workpiece optimally. Generally, cores are placed in the workpiece to fix it firmly at the production site. However, the cores must be adjusted precisely in accordance with the shape of the workpiece. A low-point melting alloy can be conveniently used instead of the cores. In this study, the influence of the supporting method for thin parts having a curved surface using a low-melting point alloy on machining accuracy is experimentally investigated. The turbine blade is selected as the experimental part. The shape is produced via end milling. The experimental results indicate that a low-melting point alloy can be closely fitted to the supporting curved surface of the turbine blade because the volume of the low-melting point alloy increases in the solidification. However, the machining accuracy is degraded when the turbine blade is deformed owing to the characteristics of the low-melting point alloy. A support method using the low-melting point alloy and an elastomer support is proposed to improve the machining accuracy. The effectiveness of the proposed method is experimentally confirmed.
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