Investigation of Kelvin Prone Force Microscopy Efficiency for Detection of Hydrogen Trapping in Carbide Precipitates

Abstract

Aging twinning-induced plasticity (TWIP) steel was obtained by aging heat treatment at 700 °C for 24 h. Scanning Kelvin probe force microscopy (SKPFM) was used to investigate the local distribution of hydrogen after electrochemical charging in TWIP steel with carbides in grain boundaries and grains. Results showed that carbides at the grain boundary adsorbed more hydrogen than those in the grain, which may be due to the simultaneous adsorption of hydrogen by carbides and grain boundaries. The numerical simulation results based on the McNabb-Foster equation showed that carbides have stronger adsorption effect than the austenite matrix.