The quality of welds can be proven by non-destructive or destructive testing. According to the state of the art, these quality checks are expensive and lower the economy and productivity. Hence, only on a random sample with few components, compared to the amount of all manufactured components, are tested in intervals. However, process monitoring can be used with high economy and low cost for a continuous quality assessment of all components. The example of resistive projection welding with capacitor discharge (CD-welding) shows how the process sequence is designed on the basis of a physically justified process understanding and how the monitoring parameters are selected. CD-welding belongs to the resistance welding methods in which the connection is made by pressing the components and simultaneously melting a projection. According to recent researches, the joint is formed differently at cd welding. Due to very high power density within very short period of time metal vaporizes and activates the surfaces. The joint occurs in less than a few milliseconds, when the activated surfaces are pressed together while the projection is plastically deformed. At the same time, molten material is pushed out of the joint plane. On this new basis of process understanding, a new machine has been developed in order to control the process purposefully and to monitor the stages of the process.

DOI: 10.32548/RS.2019.017

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