| 摘要 |
<p>Fixing device (1) made from at least two sections (3, 4) of different materials, or of materials with varying grains or degrees of hardness, one being bound to the other by a process of stored-energy welding, the first section (4), which forms a drilling bit, being of hardenable or full-hardenable metallic material, the other section (3), forming the shaft (6) and the screw head (5), being of a different metallic, preferably corrosion-resistant material or having a different grain. The adjacent ends of the sections (3, 4) are provided with, in one end, a flat end section (9) and, in the other, a conical extension (8) or an axially protruding stud small in diameter.</p> |
