Effects of Mo and B additives on hardness and the resistance of Cu-Ni alloy to wear, corrosion and corrosive wear

• Author / Creator

  Hou, Runfang

• Due to its corrosion resistance, conductivity, and modifiable mechanical properties, CuNi alloy has found a wide range of applications, especially in the marine environment. It is highly desired if the mechanical strength and wear resistance of CuNi alloy can reach a level comparable to that of steel. In this study, effects of Mo, B, and their combination on properties of CuNi alloy were investigated, including hardness and resistances to wear, corrosion and corrosive wear. The B and Mo added CuNi samples were made using an arc furnace and annealed at 600℃ for 4 hours. The samples were characterized with SEM, optical microscopy and X-Ray diffraction techniques. Wear resistances of the samples were evaluated using a pin-on-disc tester. It was demonstrated that the Mo and B additives were effective in strengthening the CuNi alloy while retaining desired corrosion resistance. In particular, the combination of Mo and B additives was more effectively than a single additive to harden the alloy, leading to considerably increased wear resistance. The modified CuNi samples show their hardness comparable to that of normalized low carbon steel. The volume loss of the 50Cu-50Ni alloy caused by wear was reduced by 59% and 56% when tested in air and 3 wt.% NaCl solution, respectively, after 2 at.% B and 2 at.% Mo were added. Mo and B additives have demonstrated their great promise as new alloying elements to modify CuNi alloys.

• Subjects / Keywords

  • corrosive wear
  • wear
  • hardness

• Graduation date

  Spring 2020

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-qgv8-9022

• License

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