抄録
In general, the atmospheres for heat treatment are composed of O2, N2, CH4, CO, CO2, H2, H2O, etc. The process of oxidation-reduction by the bright heat treatment in these atmospheres is very complicated.
This paper discusses the oxides of plain carbon steel produced by various oxidizing gases at high temperatures.
The following results were obtained.
(1) Oxides of the specimens produced by each of O2, CO2, H2O (gas), and air were much different one another in microstructures.
(2) The X-ray diffraction patterns showed that the oxides of specimens heated in H2O (gas) contained FeO more than those heated in other gases.
(3) In general, the surface of specimens consisted of the layer of α-Fe2O3, or the layer of rich in α-Fe2O3. However, its content was gradually decreased with the increase of depth from the surface.
(4) As the results of line analysis of X-ray microanalyzer, it was shown that the oxygen content of the oxidized layer was increased in linear proportion toward the surface.
