Corrosion behavior of titanium nitride coated Ni-Ti shape memory surgical alloy.

Nickel-titanium (NiTi, nitinol) shape memory alloy was nitrided using an original powder immersion reaction assisted coating (PIRAC) method in order to modify its surface properties. PIRAC nitriding method is based on annealing the samples in the atmosphere of highly reactive nitrogen supplied by decomposition of unstable nitride powders or, alternatively, by selective diffusion of the atmospheric nitrogen to the sample surface. Being a non-line-of-sight process, PIRAC nitriding allows uniform treatment of complex shape surgical implants. Hard two-layer titanium nitride (TiN)/Ti2, Ni coatings were obtained on NiTi surface after PIRAC anneals at 900 and 1000 degrees C. PIRAC coating procedure was found to considerably improve the corrosion behavior of NiTi alloy in Ringer's solution. In contrast to untreated nitinol, no pitting was observed in the samples PIRAC nitrided at 1000 degrees C, 1 h up to 1.1 V. The coated samples were also characterized by very low anodic currents in the passive region and by an exceedingly low metal ion release rate. The research results suggest that PIRAC nitriding procedure could improve the in vivo performance of NiTi alloys implanted into the human body.

[1]  M. Beyar,et al.  New treatment modality for penile urethral strictures using a self-expanding and self-retaining coil stent: UroCoil. Follow-up of 16 months after removal of the stent. , 1993, European urology.

[2]  Stanley A. Brown,et al.  Reduction of fretting corrosion of Ti‐6Al‐4V by various surface treatments , 1993, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[3]  A. Cigada,et al.  The corrosion behaviour of nickel titanium shape memory alloys , 1990 .

[4]  D. Starosvetsky,et al.  Corrosion behavior of PIRAC nitrided Ti-6Al-4V surgical alloy , 2001, Journal of materials science. Materials in medicine.

[5]  P J Gregson,et al.  Effect of surface treatment on the dissolution of titanium-based implant materials. , 1991, Biomaterials.

[6]  Buddy D. Ratner,et al.  Biomaterials Science: An Introduction to Materials in Medicine , 1996 .

[7]  D. Williams,et al.  Immune response in biocompatibility. , 1992, Biomaterials.

[8]  P. Havlík,et al.  TiN coating: surface characterization and haemocompatibility. , 1993, Biomaterials.

[9]  J. Planell,et al.  Relevant aspects in the clinical applications of NiTi shape memory alloys , 1996 .

[10]  B. Hillberry,et al.  Component wear of total knee prostheses using Ti-6A1-4V, titanium nitride coated Ti-6A1-4V, and cobalt-chromium-molybdenum femoral components. , 1988, Journal of biomedical materials research.

[11]  D. Starosvetsky,et al.  Corrosion behavior of heat-treated intermetallic titanium-nickel in hydrochloric acid solutions , 1998 .

[12]  Rolando Barbucci,et al.  Biological Performance of Materials , 2000 .

[13]  H. Lin,et al.  Wear characteristics of ion-nitrided Ti50Ni50 shape memory alloys , 1997 .

[14]  M. Barthélémy,et al.  Effect of water soluble extract of nacre (Pinctada maxima) on alkaline phosphatase activity and Bcl-2 expression in primary cultured osteoblasts from neonatal rat calvaria , 2001, Journal of materials science. Materials in medicine.

[15]  S. Radin,et al.  Titanium nitride coatings on surgical titanium alloys produced by a powder immersion reaction assisted coating method: residual stresses and fretting behavior , 2000 .

[16]  D. Williams,et al.  Biocompatibility of clinical implant materials , 1981 .

[17]  K. Endo,et al.  Effects of titanium nitride coatings on surface and corrosion characteristics of Ni-Ti alloy. , 1994, Dental materials journal.