少量のTiを添加したFe-18Cr合金の高温酸化

抄録

A study has been made on the isothermal oxidation behaviour of Fe-18Cr alloys containing 0.1 to 0.9 wt%Ti in 1 atm of oxygen at 1173∼1473 K for 86.4 ks. The weight gain increases with increasing Ti content. The addition of Ti in the range tested, therefore, appears to have no effects on improving the oxidation resistance, but rather to be deleterious. The scales formed have been mainly composed of Cr₂O₃, with Ti oxides distributing in the outer part of the scale, and in the alloy as internal oxides, respectively. When a small amount of Al, 0.5 wt%, is added to this alloy in addition to 0.5 wt%Ti, the internal oxidation of Ti has been considerably suppressed and has concentrated on the outer surface as well as in the inner part of the scale. The deleterious effects of Ti have also been observed in this case.