摘要
采用MEVVA离子源将Cr、Y、Nb离子分别注入γ -TiAl金属间化合物 ,注入能量 50—6 0keV ,注入剂量为 1× 10 17cm- 2 ,研究γ -TiAl在 10 0 0℃空气中的循环氧化行为。结果表明 ,Cr离子和Y离子注入对γ -TiAl的高温氧化性能均没有明显影响 ;Nb离子注入γ -TiAl,在氧化初期 ,抗氧化性能得到显著提高 ,但随着氧化过程的继续 (超过 10 0h) ,这种改善作用逐渐降低。实验发现 ,通过离子注入和基体合金化向γ -TiAl中加入相同元素 ,由于工艺过程的差异 ,对其高温氧化性能的影响不同。在长时间高温氧化 (10 0 0℃ )条件下 ,离子注入表面改性无法达到提高γ
A γ-TiAl intermetallic compound was implanted with Cr, Y and Nb ions respectively to a dose of 1×10 17 cm -2 at an ion energy of 50-60keV by using a MEVVA ion source. Cyclic oxidation tests were performed on this compound at an oxidation temperature of 1000℃ in air. It was found that Cr or Y ion implantation slightly affects the oxidation behavior of γ-TiAl at 1000 ℃ during the whole testing period up to 200h. The Nb ion implantation significantly improved the oxidation resistance of γ-TiAl in the initial stage of oxidation, but this improvement gradually decreased when the oxidation time was increased to more than 100h. By adding the same element, alloying and ion implantation have different effects on the oxidation resistance of γ-TiAl due to different characteristics resulted from these two processes. The modified surface of γ-TiAl by ion implantation has limited effects on improving its oxidation resistance during long term at high temperatures.
出处
《核技术》
CAS
CSCD
北大核心
2001年第1期27-32,共6页
Nuclear Techniques
