Journal of Materials Research and Technology (Sep 2022)

High temperature wear behavior of Ni-rich NiTi-based alloys

  • J.X. Liu,
  • S.B. Sun,
  • F. Chen,
  • Y.X. Tong,
  • L. Guan

Journal volume & issue
Vol. 20
pp. 440 – 447

Abstract

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Ni-rich NiTi-based alloys have been regarded as promising candidates for tribological applications because of their high hardness and excellent corrosion resistance. In this work, the effects of aging and Hf addition on microstructure and unlubricated wear properties of Ni-rich NiTi alloys, Ni55Ti45 and Ni55Ti40Hf5 alloys, were investigated. Both the aging and addition of Hf increase the microhardness of Ni55Ti45 alloy. The aged Ni55Ti40Hf5 alloy shows the largest value of microhardness resulting from the combination of the precipitation strengthening of Ti3Ni4 and H phases, and the solid-solution strengthening of Hf atom. The wear resistance of the studied alloys can be improved by the aging and Hf addition. The coefficient of friction values obtained at 400 °C are lower than that obtained at room temperature. Among the studied alloys, the aged Ni55Ti40Hf5 alloy shows the lowest coefficient of friction. The studied alloys show the same wear mechanisms, i.e. abrasive and oxidative wear at 400 °C.

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