Nanostructured beta-type titanium alloy fabricated by ultrasonic nanocrystal surface modification

作者：Kheradmandfard Mehdi; Kashani Bozorg Seyed Farshid; Kim Chang Lae; Hanzaki Abbas Zarei; Pyoun Young Shik; Kim Jung Hyong; Amanov Auezhan^*; Kim Dae Eun^*

来源：Ultrasonics Sonochemistry, 2017, 39: 698-706.

DOI：10.1016/j.ultsonch.2017.03.061

• Ultrasonic nanocrystal surface modification
• Ultrasonic vibration
• Gradient nanostructure
• beta-Ti alloy
• Nanoscale lamellae

The surface of beta-type Ti-Nb-Ta-Zr (TNTZ) alloy, which is a promising material for biomedical applications, was treated with the ultrasonic nanocrystal surface modification (UNSM) technique to enhance its hardness. As a result, a gradient nanostructured (GNS) layer was generated in the surface; the microstructure of the top surface layer consisted of nanoscale lamellae with a width of about 60-200 nm. In addition, there were lamellar grains consisting of nanostructured subgrains having unclear and wavy boundaries. The treated surface exhibited a hardness value of similar to 385 HV compared to 190 HV for the untreated alloy. It was further determined that highly dense deformation twins were generated at a depth of similar to 40-150 mu m below the UNSM-treated surface. These deformation twins led to a significant work hardening effect which aided in enhancing the mechanical properties. It was also found that UNSM treatment resulted in the formation of micropatterns on the surface, which would be beneficial for high bioactivity and bone regeneration performance of TNTZ implants.

• 出版日期2017-11