摘要
在室温和400-700℃条件下,采用1×10^17ions/cm^2注入剂量和200keV加速电压对Ti6Al4V合金进行了氦离子注入。分别采用纳米硬度仪和X射线衍射方法对Ti6Al4V合金的氦离子注入表面层（≤700nm）进行了纳米硬度、弹性模量测试和物相分析。结果表明：在室温至600℃范围内,氦离子注入温度越高,Ti6Al4V合金注入层的硬度也越高,而其弹性模量则变小。氦离子注入温度为700℃时,Ti6Al4V合金发生了软化,其弹性模量也有所提高。氦离子注入引起的硬化现象与点缺陷和Ti6Al4V合金中β相的析出有关,而软化现象则与β相的粗化和γ-TiH相的形成有关。
Ti6Al4V specimens were helium-ion implanted with constant fluence of 1×10^17 ions/cm^2 at 200keV within the temperature range from room temperature to 700℃.Nano-hardness and elastic modulus of the unimplanted and irradiated specimens were measured by means of the nano-indentation technique and analyzed using the Oliver-Pharr method.The indentation depth of all samples was 700 nm,which was comparable in magnitude to the ion range in the irradiated specimens.The phases in the surface layer of the Ti6Al4V specimens were investigated by the grazing incidence X-ray diffraction（GIXRD）.The results indicate that with the implantation temperature increasing from room temperature to 600℃,the nano-hardness and elastic modulus of the irradiated specimens increase and decrease,respectively.The implantation at 700℃,however,caused softening and slight increase of the elastic modulus of the Ti6Al4V alloy.The hardening and reduction of the elastic modulus of the Ti6Al4V alloy under implantation conditions is related to the point defects and dispersed obstacles of β-precipitates.The softening and slight increase of elastic modulus of helium-irradiated Ti6Al4V at 700℃ might be a result of the coarsening of β-precipitates and the new γ-TiH phase formed in α-phase.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2010年第5期25-29,33,共6页
Journal of Materials Engineering
基金
教育部科学技术研究重点项目(205139)
