ROLLING DIE AND METHOD FOR MANUFACTURING SAME

    公开(公告)号:EP4094872A1

    公开(公告)日:2022-11-30

    申请号:EP20926385.4

    申请日:2020-03-26

    申请人: OSG Corporation

    发明人: HISADA, Teruya

    IPC分类号: B23G7/02 C23C8/26 B21H3/06

    摘要: Provided is a rolling die that increases the durability of a nitrided molded surface. The rolling die (1) includes a tool base material that is made of steel and has a molded surface (2) on which a plurality of working teeth (10) is formed. The tool base material includes a nitride layer (15) in which nitrogen is diffused. The nitride layer (15) is disposed to reach a position that is 20 to 70 µm in depth from the molded surface (2). The molded surface (2) has a surface hardness of at least 1100 HV. The rate of depth change from the depth (D1) of the nitride layer (15) at crests (11) of the working teeth (10) to the depth (D2) of the nitride layer (15) at roots (13) of the working teeth (10) is not higher than 30%.