| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a flat die for rolling, which can be manufactured by a conventional manufacturing man-hours or cost while assuring a demand level of an accumulation pitch error of a high hardness material in form rolling. <P>SOLUTION: The flat die for rolling includes a first lead-in part 21 and a second lead-in part 23 each different in surface roughness of working teeth 20, and a stress buffer part 22 between the first lead-in part 21 and the second lead-in part 23. The surface roughness of the working teeth 20 of the stress buffer part 22 is gradually decreased toward the second lead-in part 23 side from the first lead-in part 21 side. Furthermore, the surface roughness of the working teeth 20 of the first lead-in part 21 is made to fall within the range of 20-35 μmRz, and the surface roughness of the working teeth 20 of the second lead-in part 23 is made to fall within the range of 1-4 μmRz. Moreover, the surface roughness of the working teeth 20 of the stress buffer part 22 is gradually decreased within the range of 1-35 μmR<SB POS="POST">z</SB>. <P>COPYRIGHT: (C)2012,JPO&INPIT |
