Method for determining the temperature in a joining zone

Method for determining a temperature in a joining zone in a vibration welding process, wherein a first joining partner (1) and a second joining partner (2) are welded together, characterized in that the first and second joining partners (1, 2) act as thermocouples, wherein a potential difference (P1) between the first and second joining partners (1, 2) is detected during the welding process by means of a first measuring element (5), which is in contact with the first joining partner (1) at a cold junction (3), and a second measuring element (10), which is in contact with the second joining partner (2) at a distance from a hot junction (8),

• wherein the second measuring element (10) has, in the region of contact (9) with the second joining partner (2), a temperature which is higher than the temperature of the cold junction (3) and a material of the same type as the second joining partner (2),
• in that the potential difference (P1) is matched with material-specific calibration data and is processed by means of a data processing system (7), and in that the welding process is controlled according to the determined potential difference (P1),
• in that the first joining partner (1) is designed in the form of a stranded cable,
• in that the first measuring element (5) is designed as a measuring lead which is connected at its first end to the first joining partner (1) and at its second end at a measuring point (6) to the data processing system (7),
• in that the second measuring element (1) is designed as a measuring lead which is connected at its first end to the second joining partner (2) and at its second end at a second measuring point (11) to the data processing system (7),
• in that the first joining partner (1) and the first measuring element (5) are made of aluminum,
• in that the second joining partner (2) and the second measuring element (10) are made of copper,
• in that the temperature of the cold junction corresponds to the ambient temperature of approximately 20° C. and in that the contacting in the region of the hot junction (8) takes place at a temperature higher than the ambient temperature.