Product Code: JLA_3_2_9

Authors:
Rehan Akhter
W. M. Steen
Dept. of Mechanical Engineering

K. G. Watkins
Dept. of Materials Science and Engineering, University of Liverpool, Liverpool L69 3BX, England

This paper discusses the lap welding of zinc‐coated mild steel sheet using a laser. This process is of great interest to the manufacturers of cars, washing machines and other components made from sheet steel and subject to corrosion. Conventional and high‐energy density welding of this material results in explosive ejection of the zinc vapor and an unsatisfactory weld. Several techniques are presented for the removal of the zinc from the interface or the control of the zinc vapors. Of the processes discussed in the paper the use of a gap between the sheets to vent the zinc vapor is shown to produce satisfactory welds. The resulting welds made both by this gap technique and by welding uncoated material were tested for fatigue, impact resistance, mechanical strength, hardness and corrosion resistance to salt solutions. The welds were made using a variety of lasers and the comparison in performance of these lasers is presented.