Corrosion Science and Technology

The Corrosion Science Society of Korea (한국부식방식학회)
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Effects of Mo Content on Surface Characteristics of Dental Ni-Ti Alloys

치과용 Ni-Ti합금의 표면특성에 미치는 Mo함량의 영향

  • Han-Cheol Choe (Department of Dental Materials, College of Dentistry, Chosun University) ;
  • Jae-Un Kim (Department of Dental Materials, College of Dentistry, Chosun University) ;
  • Sun-Kyun ark (BPC Co)
  • Received : 2023.02.21
  • Accepted : 2023.02.23
  • Published : 2023.03.02
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Abstract

Ni-Ti shape memory alloy for dental nerve treatment devices was prepared by adding Mo to Ni-Ti alloy to improve flexibility and fatigue fracture characteristics and simultaneously increase corrosion resistance. Surface properties of the alloy were evaluated. Microstructure analysis of the Ni-Ti-xMo alloy revealed that the amount of needle-like structure increased with increasing Mo content. The shape of the precipitate showed a pattern in which a long needle-like structure gradually disappeared and changed into a small spherical shape. As a result of XRD analysis of the Ni-Ti-xMo alloy, R-phase structure appeared as Mo was added. R-phase and B2 structure were mainly observed. As a result of DSC analysis, phase transformation of the Ti-Ni-Mo alloy showed a two-step phase change of B2-R-B19' transformation with two exothermic peaks and one endothermic peak. As Mo content increased, R-phase formation temperature gradually decreased. As a result of measuring surface hardness of the Ti-Ni-Mo alloy, change in hardness value due to the phase change tended to decrease with increasing Mo content. As a result of the corrosion test, the corrosion potential and pitting potential increased while the current density tended to decrease with increasing Mo content.

Keywords

Acknowledgement

본 연구논문은 2022년 조선대학교 교내연구비 지원으로 수행되었음.

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