Electron beam welding of magnesium AZ91D plates

Magnesium AZ91D plates were welded by an electron beam (EB). The integrity of the welded specimens was investigated by X-ray radiography and ultrasoni c techniques. Optical and scanning electron microscopy were used to investi gate the microstructural changes that occurred during welding. Mechanical p roperties were determined by standard tension tests. It was found that Mg A Z91D cast alloy can be EB welded with a negligible amount of discontinuitie s and with a minimal heat-affected zone (HAZ). The rapid melting and subseq uent resolidification during welding induces microstructural refinement, wh ich increases both strength and ductility of the alloy. it was also observe d the microstructure is finer with less heat flux.