Inhibition of hydrogen absorption due to wear between Ni–Ti superelastic alloys in NaCl solution by H2O2 addition

Abstract

• Ni–Ti superelastic alloy absorbs hydrogen due to wear in NaCl solutions without marked corrosion. • The amount of hydrogen absorbed in NaCl solutions is almost as much as that in purified water. • The hydrogen absorption due to wear is inhibited by adding a small amount of H 2 O 2 into solutions. The inhibition of hydrogen absorption due to wear between Ni–Ti superelastic alloys in 0.15 M NaCl solution has been attempted by adding H 2 O 2 . For comparison with previous results in purified water, the present wear test has been conducted under the same conditions as in the previous test except for the test solutions. The amounts of wear loss and hydrogen absorbed during the wear test in the NaCl solution without H 2 O 2 are almost as much as those in water, suggesting hydrogen embrittlement. Upon the addition of 0.01 M H 2 O 2 into the NaCl solution, the corrosion potential during the wear test shifts in the noble direction; the amount of absorbed hydrogen substantially decreases. The present results indicate that the addition of a small amount of H 2 O 2 into solutions is effective for the inhibition of hydrogen absorption due to wear.