Cross-Wire Projection Welding of Aluminium Alloys in relation to Pneumatic and Servomechanical Electrode Force Systems

摘要

The article presents the analysis of the cross-wire projection welding of aluminium wire in relation to conventional, i.e. pneumatic, and servomechanical electrode force systems. The analysis was performed using FEM calculations, which were next subjected to experimental verification. The calculations and experiments were performed using wire made of Al 5182 (diameter of 4.0 mm) as well as various force values (pneumatic system) and various values of electrode travel (servomechanical system). The FEM calculations were used to analyse a number of parameters, including the penetration of the wires into each other, waveforms instantaneous power as well as the diameter and volume of the weld nugget. The experiments involved the recording of welding current and voltage as well as electrode force and travel. The tests also involved destructive (peeling test) and metallographic tests.The tests were focused on process optimisation in relation to force control and, as a result, to the control of welding power space distribution enabling the concentration of energy in the central zone of the weld. When the pneumatic force system was used, the above named zone was characterised by an incomplete fusion instead of interpenetration. The practical implementation required the use of the servomechanical electrode force system.