钇离子注入改善Co-40Cr合金表面氧化膜粘附性的作用

IMPROVEMENT OF ADHESION OF THE SCALE FORMED ON CO-40Cr(wt%) ALLOY BY YTTRIUM IMPLANTATION

用声发射（AcousticEmission）方法及扫描电镜SEM／EDXA，对Co－40Cr合金在1000℃空气中20h恒温氧化后表面氧化膜的开裂和剥落进行了研究．并与该合金表面离子注入3×1016Y+／cm2和3×1017Y+／cm2后的氧化结果进行了比较．结果表明，离子注钇后极大地改善了合金表面氧化膜的抗开裂和抗剥落性能．此外，用声发射方法能够间接地测量出氧化膜／合金界面处“预存缺陷”（pre-existingdefects）的分布情况．离子注钇改善合金表面氧化膜的粘附性与注钇后减小了界面处“预存缺陷”的数目及平均大小有关．

Acoustic emission (AE) and SEM/EDXA were used to study the cracking and spalling behavior of the scale formed on Co-40Cr alloy after 20 h isothermal oxidation in air at 1000℃. By comparing the cracking and spalling behavior of scale formed on 3×1016Y+/cm2 and 3×1017Y+/cm2 implanted and non-implanted Co-40Cr alloys, it was found that yttruim implantation greatly improved the anti-cracking and anti-spalling properties of the scale. AE was used to study the distribution of pre-existing defects at the scale/alloy interface. The improvement of adhesion of the scale formed on yttrium-implanted aloy was attributed to the decrease in the size and number of pre-existing defects at the scale/alloy interface.