研究了含8 mass%Y的Ag-Y合金在105 Pa和10-15 Pa两个氧压于700℃的氧化.结果表 明，在105 Pa的氧化很快，并遵循近似的抛物线规律；10-15 Pa的氧化则很慢且偏 离抛物线规律.在高氧压仅发生Y的原位内氧化，这主要是氧快速向内渗透而没有Y明显地向 外扩散所致；在低氧压则生成含Ag颗粒的Y2O3外氧化层，而其Y的内氧化层则远较高氧 压者薄.内氧化Y2O3颗粒沿深度而变化，近表面处小并呈圆球状，随深度增加逐渐变大 并拉长；在深处呈针状且垂直合金表面.此外，在两种氧压下合金最表面有Ag层或分散的Ag 颗粒生成.
The oxidation of a silver-based alloy Ag-8Y was studied in 105 Pa and 10-1 5 Pa oxygen at 700℃.The oxidation rate under high P(O2) is very fast and f ollows approximately parabolic rate law,however under low P(O2) is much sl ower and quite irregular with large deviations from parabolic behavior.Under hig h P(O2) the alloy experiences only an internal oxidation of Y without any significant outward Y diffusion,as a result of a fast oxygen penetration.Under l ow P(O2)the alloy forms an almost continuous Y2O3 layer containing Ag particles,plus an internal oxidation zone of Y much thinner than under high P (O2).In both cases pure Ag metal appears on the top surface as a continuous layer for high P(O2) and as separate particles for low P(O2).The int ernal Y2O3 particles in the matrix change shape with depth,being small and g lobular close to the alloy surface but larger and acicular,elongated nearly perp endicularly to the alloy surface,at larger depths.
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