最終更新日：2023/07/13
This has been realized by having so-called functionally-gradated structure that the cutting edge is hard, and the hardness is gradually decreased to the core, which makes compressive residual stress generate at the cutting edge.
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This has been realized by having so-called functionally-gradated structure that the cutting edge is hard, and the hardness is gradually decreased to the core, which makes compressive residual stress generate at the cutting edge.
音声機能が動作しない場合はこちらをご確認ください
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