摘要 |
The disclosure relates to a method of insuring the tightness of a fastener including forming a three-dimensional annular member in an austenite phase using a press, cooling the annular member to a temperature lower than the temperature for starting an austenite transformation, fastening the fastener with the annular member to flatten the annular member, and returning the temperature of the annular member to a higher than austenite temperature so that the recovery power of the annular member for returning the annular member to the three-dimensional shape in the austenite phase generates a fastening force for the fastener. |