A Modified Electrochemical Nanoindentation Setup for Probing Hydrogen-Material Interaction Demonstrated on a Nickel-Based Alloy

An electrochemical charging setup was implemented in a nanoindentation system to evaluate the sensitivity of technically relevant materials to hydrogen embrittlement. Corresponding changes in the nanomechanical properties such as the hardness, Young’s modulus and pop-in load can be measured and interpreted. A nickel-based alloy was examined in solution-annealed and aged condition. A hydrogen-induced hardness increase of 15% was measured for the solution-annealed sample. Aging the alloy leads to a reduced influence of hydrogen, lowering the hardness increase to 5%. For the solution-annealed sample, hydrogen charging-induced surface steps were observed and characterized with laser confocal microscopy and electron backscatter diffraction to reveal plastic deformation.