Hydrogen effects on directional solidification of Te-doped cast irons

Directional solidification experiments showed that small additions of hydrogen have a large effect on the gray-white and white-gray transition velocities of Te-doped cast irons. Hydrogen seemed to reduce compounds of Te, which allowed more Te to remain in the liquid solution and to adsorb on the graphite/liquid iron growth front interfaces, which in turn, reduced the graphite growth kinetics and permitted the growth of white iron to dominate.