| 摘要 |
A screw consisting mainly of stainless steel with a head (6) and a shank (7) with a point (2) and at least one threaded portion, characterized in that the stainless steel contains a maximum of 0.1 % C, preferably a maximum of 0.08 % C, in that it is stabilized with at least one of the elements niobium, tantalum and titanium in a total content amounting to at least 5 times the carbon content, but a maximum of 1 %, and in that at least the screw point (2) and a length (8) of said at least one threaded part have a surface-hardening layer (3) produced by ion nitriding, which has a thickness of 0.01-0.2 mm and a hardness of at least 900 HV, preferably 1000-1300 HV. The invention also relates to production of a stainless screw by means of a method which comprises ion nitriding. |
