| 摘要 |
A method for producing a closed-end blind rivet (1) comprising the following steps: providing a mandrel (2) having a mandrel head (4) and having a breakneck portion (6) located between said head and a stem (5), which breakneck portion has an initial breaking strength, inserting the mandrel head (4) into an opening in a preformed blank (13), and extruding the blank (13) over the mandrel (2) to form a rivet body (3) in such a manner that a first, closed end of the rivet body (3) closely surrounds the mandrel head (4) and the interior of the rivet body (3), wherein the tensile stress on the breakneck portion (6) during extrusion of the rivet body (3) is less than the initial breaking strength of the breakneck portion (6), and forming a flange (9) at a second, open end of the rivet body (3), reducing the tensile strength of the mandrel (2), and thus of the initial breaking strength of the breakneck portion (6), by heat treatment of the blind rivet (1) composed of the rivet body (3) and mandrel (2). The invention also relates to a closed-end blind rivet produced by such a method. |
