Advanced small-scale characterization of hydrogen embrittlement

Abstract

A large amount of micro-cantilevers were made using a focused ion beam (FIB) microscope. The cantilevers were made to be tested under cyclic loading in a triboindenter to determine the hydrogen effect on the grain boundaries of a FeSi-alloy (3wt% Si and 0,02wt% C). The hydrogen effect was determined by analyzing load-displacement curves where the displacement were from 3 to 5 μm vertically, under atmospheric and acidic conditions (introduction of hydrogen). The focus of this report has been on the fabrication of the micro-cantilevers.

A machining procedure for making cantilevers of good quality is presented in this report. It is made for cantilevers of the dimensions: 14,5 μm length, 4 μm width, 2,6 μm height, and an elevation of 5 μm from the cantilever to the sample floor, but has been used to make cantilevers of variying dimensions. The hydrogen effect on one of the samples has been determined, where it was found that the introduction of hydrogen on the grain boundary lowered the needed force to bend the cantilever by 80 μN.