In this study the hydrogen trapping phenomena were investigated by thermal analysis in which the trapping effect of one trapping site could be distinguished from others and the amount of trapped hydrogen was measured absolutely by gas chromatograph.
Only to show the hydrogen trapping phenomena by TiC particles in iron, the amounts of TiC particles in the specimens were varied while other trapping sites were kept constant and minimized by holding at 700℃ for 24 hr.
The hydrogen evolution rate peak formed by hydrogen trapped in TiC-ferrite interface was observed at 723℃ when the heating rate was 3℃/min.
The trap activation energy, trap binding energy and trap density of a trapping site are important to study hydrogen diffusion in metals containing trapping sites which is function of these values of the trapping sites.
The peak temperature of a trapping site is increased with heating rate. The trap activation energy necessary for hydrogen detrapping from TiC-ferrite interface was obtained from these heating rates and peak temperatures measured experimently and was 20.7 Kcal/mol.
The TiC-hydrogen binding energy can be obtained from the equilibrium relation between the hydrogen concentration trapped in TiC particles and the lattice hydrogen concentration at each hydrogen charging temperature in one atm hydrogen pressure.
From the experimental results of the hydrogen charging temperature and corresponding trapped hydrogen concentration it was computed that the trap binding energy of TiC-ferrite interface was 6.7 Kcal/mol.
The trap densities of the specimens used in this study were also yielded.
The hydrogen energy levels around TiC-ferrite interface were suggested from the trap activation energy and trap binding energy measured.
