Hello! Does anyone have experience welding 7475 Al alloy by using resistance spot welding method? What are the welding parameters? It is hard to weld 7475 alloy by resistance spot welding. I want to weld 1.6 mm bare 7475 plate to the same plate. Thank you.
I have some information on resistance spot welding of AlMg 0.4Si 1.2 alloy(Total of other elements besides Aluminium 3.0%). Yield strength 220 Mpa.
An extensive research on Experimental and Theoretical analysis of resistance spot welding of this Aluminium alloy sheets was carried out at Stuttgart University. The following report gives the complete details.
Forschungsvorhaven AIF-Nr. Q10/DVS-Nr. 4. 191 by Professor Dr. Ing. Dr. Techn. E. h. Karl Kussmaul (1993) (in German). The English translation of the title is ‘Numerical analysis of the mechanical and thermal processes in resistance spot welding’.
Some data on resistance spot welding of this alloy, given below, are based on that report.
Sheet thickness = 1.25 mm, Welding current 28kA, Electrode force 2.5 kN, rounded tip electrode with tip radius 75 mm, weld time 20 ms to 60 ms. At 20 ms the weld is barely visible while the weld has large blow hole at 60 ms. It is also observed that the welding parameters depend significantly on the surface condition of the sheet, whether it is (a) as received, (b) mechanically cleaned or (c) chemically cleaned. It is more so in case of Aluminium alloy than steel.
Dear Professor;
Thank you for your valuable experience. I searched the document or report that you adviced me but I could not find such a report. Also the parameters that you told me are for 7475 or you studied AlMg 0.4Si 1.2 alloy?? Thank you.
The data is for AlMg0.4Si 1.2 alloy and not for 7475 alloy which has higher alloy content of about 11-12%. However, thermal properties like thermal conductivity, melting point, latent heat (and to some extent electrical conductivity) depend on bulk element (Al here) and do not change significantly with addition of small amount of alloying elements. So I thought that the welding data may be useful. Also in this particular case the welding was performed on a medium frequency welding machine ( used generally in robotic welding). Of course, metallurgical and mechanical properties will differ greatly. This is an old report (1993) and may not be existing on internet although you may look at the web repository of Stuttgart University.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Annealing
- Metallurgy