Determination of energy flows for welding processes

The efficiency as well as the knowledge of the energy flow of welding processes is a fundamental coefficient to realize high-quality joints. The increasing use of high-strength materials with a small processing range as well as the demand to simulate resulting component properties increase the demand of exact knowledge of the heat input. Experiments show that the heat input into the component is highly influenced by the selection of welding parameters. Measurements confirm that it is possible to increase the efficiency of welding processes for example by reducing the wire feed speed in gas metal arc welding (GMAW), using carbon dioxide shielding gas or increasing the stick-out length. On the contrary, increasing the current or voltage or reducing the shielding gas flow reduces the process efficiency. The difference between the lowest and highest achievable value of efficiency can be more than 15 % for one specific welding process. In this work, the efficiencies of different groups of welding processes are compared. Due to the use of unique measurement systems and systematical analyses of influencing parameters, a comprehensive overview for different welding processes is possible for the first time.