Abstract
Temper color produced in grinding is generally used for the index of thermal damages suffered on the ground surface. Although, there are some problems about the oxidation process of ground surface and the microstructure of oxide layer which represent the temper color. In the present research, the difference of oxidation process between ground surface and buffed one is compared experimentally, and the microstructure of subsurface layer is investigated with some micro analysis methods such as SIMS, TED, etc. The results obtained are as follows: (1) Fresh surface produced by abrasive grains is activated and tend to be oxidized. (2) Burned surface is covered with thin Fe3O4 film with thickness of scores of nano-meters. (3) Under the film, there is a compound layer composed of iron and iron oxide. The thickness of the layer is up to hundreds of nano-meters. (4) The compound layer has many micro cracks and it appears to be a thin layer composed of micro vertical pillars.
