Effects of laser shock peening on the corrosion behavior and biocompatibility of a nickel–titanium alloy

Abstract

Nickel-titanium (NiTi) alloy is an attractive material for biomedical implant applications. In this study, the effects of laser shock peening (LSP) on the biocompatibility, corrosion resistance, ion release rate and hardness of NiTi were characterized. The cell culture study indicated that the LSP-treated NiTi samples had lower cytotoxicity and higher cell survival rate than the untreated samples. Specifically, the cell survival rate increased from 88 AE 1.3% to 93 AE 1.1% due to LSP treatment. LSP treatment was shown to significantly decrease the initial Ni ion release rate compared with that of the untreated samples. Electrochemical tests indicated that LSP improved the corrosion resistance of the NiTi alloy in simulated body fluid, with a decrease in the corrosion current density from 1.41 AE 0.20 μA/cm 2 to 0.67 AE 0.24 μA/cm 2 . Immersion tests showed that calcium deposition was significantly enhanced by LSP. In addition, the hardness of NiTi alloy increased from 226 AE 3 HV before LSP to 261 AE 3 HV after LSP. These results demonstrated that LSP is a promising surface modification method that can be used to improve the mechanical properties, corrosion resistance and biocompatibility of NiTi alloy for biomedical applications.

Laser shock peening (LSP): Electrochemical and hydrodynamic investigation of corrosion protection pre-treatment for a copper surface in 3.5 % NaCl medium

“…This shows that there was a tendency to reduce the corrosion rate in all the laser peened samples in comparison to the unpeened Cu, whereas the highest performance in corrosion rate reduction was found at LSPVC 50 %. The results not only confirm that the LSP modification is optimum at LSPVC 50 % but also showed that the LSP process is an effective method for Cu corrosion mitigation [7,9,19,51].…”

“…In another development, the corrosion resistance of a biodegradable metallic implant (magnesium-calcium alloys) treated by LSP showed an increase in corrosion resistance by more than a 100-fold in simulated body fluid electrolyte as reported by Guo et al [18]. Similarly, Zhang et al [19] reported a wide positive shift in the corrosion potential of nickel-titanium alloy from − 440 mV to − 80 mV (a difference of − 360 mV) and reduction in corrosion current density from 1.41 to 0.67 μA cm − 2 for the untreated and the LSP treated surfaces respectively, tested in a simulated body fluid. This result by Zhang group was accompanied by an increase in hardness value from 226 to 261 HV due to the LSP treatment.…”

The Effect of Laser Nitriding on Surface Characteristics and Wear Resistance of NiTi Alloy with Low Power Fiber Laser

“…Sci. 2021, 11, 515 2 of 10 laser shock peening can increase the surface microhardness and enhance the mechanical property (such as wear-resistance) of NiTi alloy [13]. In our previous research, we also got similar results when the metals, such as aluminum, high strength, and NiTi alloy, were processed with laser shock peening [14][15][16].…”

Computer‐Aided Analysis of the Corrosion Inhibition by Carbon‐Based Thin‐Film Coating on Vascular Bare Metal Stent Models

“…Values of each material are given in Table 3. [66][67][68][69][70][71][72] For both anodic and cathodic behavior of a corroding material, electron transfer which is leading to electric current is directly associated in a corrosion process. Therefore, corrosion speed and rate depend on the releasing electron number and current flow between anodic and cathodic regions in a structure.…”