Shape Memory Alloys (SMAs) are a group of intermetallic compounds, which can undergo deformation at one temperature, and then recover their original undeformed shape upon heating above their transformation temperature. Superelasticity occurs just above the alloy’s transformation temperature in a very narrow range. In this case no heating is necessary to cause the deformed shape to recover upon load relieve to its original undeformed shape. It has to be emphasized that nitinol exhibits enormous elasticity when compared with other medical metal alloys. In recent years, the use of nitinol (NiTi), almost equiatomic binary (50:50 ratio) intermetallic compound of nickel and titanium, has been steadily growing, particularly in medical and dental devices markets. However, broader and further application of nitinol has been slowed down by leaking nickel and unavoidable inclusions during producing in this compound. This work is to present some electrochemical treatment methods in view of reducing of both these phenomena. It appears that changing electrical conditions of electropolishing (EP) above the plateau region (EP+) may improve the quality of surface obtained on NiTi of over 60% in comparison with as-received (AR) nitinol part. What’s more, introducing a magnetic field into the electrolysis system results in numerous positive features of nitinol surface and increase of mechanical properties. Thus the magnetoelectropolishing (MEP) process appears to increase higher the fatigue resistance of the treated NiTi part. The experiments carried out on chirurgical needles show an unusual triple (and higher) growth in resistance to bending until fracture. Further increase in fatigue resistance is usually limited by different size inclusions appearing on the nitinol part surface under magnetoelectropolishing (MEP).
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