The technique of tinning on magnesium has been used to improve the tungsten inert gas (TIG) lap weldability of dissimilar alloys of dissimilar metal Al 6061 to Mg AZ31B. The composition at the interface of the samples welded both directly and after tinning on magnesium was mapped by electron probe microstructure analysis (EPMA). Results revealed that tinning on the magnesium plate could eliminate the factors which affect the wet ability at the interface of the samples TIG welded directly. Tinning did not prevent the interaction between Mg and Al to form intermetallic compounds completely, but reduced the intermetallic compounds to some degree.

Two series of samples of single-layer IrMn and IrMn/FePd bilayer films, deposited on a single-crystal MgO substrate at different IrMn deposition temperatures (Ts = 300–700 °C), were investigated using magnetron sputtering. L12 ordering was revealed for the 30 nm-thick IrMn epitaxial (001) films with Ts ≥ 400 °C, determined by synchrotron radiation x-ray diffractometry (XRD). XRD results also provide evidence of the epitaxial growth of the IrMn films on MgO substrate. Increasing Ts from 400 to 700 °C monotonically increases the ordering parameter of L12 phases from 0.17 to 0.81. An in-plane exchange bias field (Heb) of 22 Oe is obtained in a 10 nm-thick FePd film that is deposited on the disordered IrMn films. As the L12 ordering of the IrMn layers increases, the Heb gradually decreases to 0 Oe, meaning that the exchange bias behavior vanishes. The increased surface roughness, revealed by atomic force microscopy, of the epitaxial IrMn layers with increasing Ts cannot be the main cause of the decrease in Heb due to the compensated surface spins regardless of the disordered and ordered (001) IrMn layers. The change of antiferromagnetic structure from the A1 to the L12 phase was correlated with the evolution of Heb.