Nanoscale surface properties of a Ni-Mn-Ga 10M magnetic shape memory alloy

► A surface layer of ∼2.5 nm and rich in Mn and Ga oxides is established with XPS. ► Nanoindentation is applied on electropolished and mechanically polished crystals. ► A similar type of oxide layer appears both in the electropolished and mech. polished surface. ► In the electropolished surface elastic loading is followed by a notable pop-in of the indenter. ► The pop-in is absent when indenting the mechanically polished surface.