Study of Condition of Disappearance of Ordered phase in High Silicon Steels

摘要

The ordered phase was tried to disappear in 6.5 percent Si steel to reduce the power loss and enhance the economic interests. They were prepared by the conventional casting or spray forming method, and they were investigated using the transmission electron microscopy (TEM). The variation in the methods of preparing the specimen did not result in any difference in suppressing the ordered B2 phase in the Fe-Si binary system. It was almost impossible to suppress this ordered phase keeping the silicon level as high as 6.5 percent even after the heat treatment at 1000 deg C for 24 hr or after hot rolling. It was necessary to change the silicon level and control the cooling rate to prevent the ordering reaction, especially, in cooling after heat treatments. The silicon level of 5.8 percent was obtained as a maximum desirable value.