Fatigue performance of Ti6Al4V alloy treated with laser-assisted burnishing

Titanium alloys are highly sensitive to surface integrity, and any deficiencies can significantly reduce their service life. Burnishing titanium alloys can enhance surface integrity and mechanical properties, thereby improving reliability and lifespan. This study introduces laser-assisted burnishing (LAB) technology to enhance the properties of Ti6Al4V alloy. The research encompasses LAB finite element modeling and empirical application. The finite element model integrates real-time temperature fields and explicit dynamic burnishing, elucidating the influence of burnishing temperature and force on surface residual stress, thus providing theoretical guidance for process optimization. Experimental results indicate that LAB significantly improves the surface integrity of Ti6Al4V. Increasing the burnishing temperature enhances the burnishing effect. Compared to turning, burnishing at room temperature, 100 degrees C, and 200 degrees C increased the low cycle fatigue life by 7.32 times, 11.11 times, and 27.56 times, respectively. The improvement in fatigue life is attributed to enhanced surface integrity, with stress concentration being the primary factor affecting fatigue life.