Surface characterization of NiTi modified by plasma source ion implantation

✍ Scribed by L. Tan; W.C. Crone

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 453 KB
• Volume: 50
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(02)00251-3

✦ Synopsis

This paper reports the novel application of an oxygen ion plasma for surface modification of a shape memory alloy. The surface characterization of oxygen ion implanted Ti-50.7 at% Ni alloy samples was performed with the assistance of Auger electron spectroscopy, X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy techniques (TEM). TEM identified amorphous TiO 2 and crystalline phases of Ti 11 Ni 14 and Ti 4 Ni 2 O x . XPS results reveal that the surfaces of control samples are covered with predominantly TiO 2 and traces of TiO and NiTi, as well as NiO and Ni 2 O 3 . At the surface of oxygen-implanted samples, however, only TiO 2 and trace amounts of Ni 2 O 3 , NiO and NiTi were observed. TiO and NiO exist in much larger range than other oxides, and TiO extends to the oxide-metal interface. These results are especially noteworthy because of their implications for interpreting corrosion, wear, and biocompatibility behavior.