抄録
The transmission Kossel (TK) technique has been applied in an attempt to elucidate the origin of potential nuclei of the celebrated (110)[001]secondary grains in hot-rolled sheets of high induction grain oriented silicon steel containing a small amount of Mo. It is observed in the microstructure in the vicinity of the surface of the hot-rolled sheets that the development of recrystallized grains is noticeably retarded and the polygonized {110}• <001> grains are preferentially, formed. In TK measurement there are two types of polygonized {110}<001> grains at a depth of 1/10 the sheet thickness under the steel surface; large polygonized (110)[001] grain possessing highly oriented (110)[001] areas with sharpened TK patterns and small polygonized {11O} <001> grains with all the diffused TK patterns. The highly oriented (110)[001] areas inside the former large polygonized (110)[001] grains are the origin of the potential nuclei of (110)[001] secondary grains. The frequency of generation and the areal fraction of (110)[001] secondary nuclei in the hot-rolled steel containing a small amount o f Mo are approximately three times as large as those found in steel containing no Mo. It is believed that the high induction grain oriented silicon steel containing a small amount of Mo has lower iron loss due to the development of (110)[001] secondary grains having small grain sizes.
