| 摘要 |
The screw has a shaft (12), and a thread (21) extending from a free end (15) of the shaft, where the thread comprises a cutting body (26) in radially opened recesses. The material of the cutting body has a larger hardness than the hardness of the thread, where radial outer contour of the cutting body partially projects above the thread. The height of the thread is constant at the free end and the height of the radial outer contour decreases stepwisely at the free end of the shaft, where the thread is formed as a single-piece with the shaft. |
