| Title |
Study on the Distribution of Sulfur in Silicon - iron and the Pinning of Secondary Recrystallization by Autoradiography |
| Abstract |
Radioactive sulfur(S^(35)) in the form of powdered FeS^(35) was introduced into the sulfur-free silicon-iron. The ingot was hot rolled at 950˚∼1000℃ to certain thickness such that subsequent cold rolling with 80% reduction in thickness resulted in 0.3∼0.4㎜ thick samples. 0.025w/o S^(35)-melted silicon-iron, sulfur-free 3.26w/o Si silicon-iron, cold rolled commercial silicon-iron and manganese-free 3.3w/o Si silicon-iron sheets samples were put together into the fused clear quartz capsules with dry pure hydrogen to a pressure of 25㎝ Hg. The sealed capsules were heat treated at various constant temperatures and then were rapidly ejected from the furnace and quenched into ice water by crushing the capsules. Autoradiography by using the AR-10 stripping film which was established by the author, was applied for specimens. Microstructures, autoradiographs and electron-microstructures were studied. It was found qualitatively that: (1) cold rolled silicon-iron showed relatively uniform distribution of sulfur in the alloy. (2) hotrolled silicon-iron showed the segregation of sulfur in the grain boundaries and uniform distribution of sulfur in the matrix. (3) the amount of grain boundary diffusion depends on the prior amount of sulfur and manganese in the silicom-iron. (4) The pinning mechanism seems to be the equilibrium grain boundary adsorption of sulfur. |