Iron Whisker Surface Rearrangements Resulting from the Hydrogen Reduction of Oxides and from Thermal Etching

Abstract

The hydrogen reduction of high-temperature oxidation products grown on iron whiskers produces iron surfaces whose topography depends on the orientation of the surface that was oxidized. The different topographies for {100} and {110} surfaces are shown, and the dependence is further illustrated on the polycrystalline iron surfaces which result from the heating of a single-crystal α iron whisker through its transformation temperature of 910°C. Rearranged surfaces covered with parallel striations and unusual dendritic surface structures are shown and discussed. Both the striations and dendrites are the result of thermal etching of a ``polycrystalline'' iron whisker at temperatures between 800°–1200°C.