Scanning Tunneling Microscopic Observation of the Surface Topography of Metallographic Specimens

In this paper, surface topographies of metallographic specimens after having been ground by 1000# waterproof abrasive paper, polished mechanically, and polished electrochemically, were investigated by scanning tunneling microscopy. The undulations were compared with those caused by the surface relief effects associated with martensite in a Cu-28.3Zn-3.3A1 alloy and Widmanstنtten ferrite in an Fe-0.37C (wt.%) alloy. The results indicate that the height of the surface reliefs is one order larger than that of specimen after having been polished mechanically and is two orders larger than that of specimen after having been polished electrochemically. Therefore, a scanning tunneling microscopic quantitative study on the surface relief effects is feasible and believable, if metallographic specimens are carefully prepared.