Assessment of fatigue and corrosion fatigue behaviours of the nitrogen ion implanted CpTi

• Fatigue and corrosion fatigue life were evaluated for Ti base material.
• Nitrogen ion implantation can improve surface properties of Ti base material.
• Formation of nitride phase can increase service life of Ti base material.
• The corrosion pit growth law for Nii-Ti specimen was established.
• The Pr = (0.021 × σ – 5.121) × t0.78 law can estimate the service life of Nii-Ti.

The fatigue and corrosion fatigue behaviours of commercially pure titanium (CpTi) have been particularly studied because the requirements of titanium (Ti) base materials are widely used for biomedical applications. The optimal properties of CpTi surface can be preserved by nitrogen ion implantation at a certain dose and energy. Still the fatigue and corrosion fatigue behaviours of nitrogen ion implanted CpTi (Nii-Ti) must be verified. This study performs the fatigue tests for CpTi and Nii-Ti specimens in a laboratory air and the corrosion fatigue tests for Nii-Ti specimens in a saline solution. Effects of nitrogen ion implantation on surface properties can improve the fatigue strength, fatigue life and corrosion fatigue life of Ti base materials. The corrosion pit growth law has been established on the basis of empirical data for predicting the corrosion penetration rate to estimate to the service life of Nii-Ti.

Figure optionsDownload as PowerPoint slide