Abstract: The tested grainoriented silicon steel was deformed at 30 % rolling reduction at 1 100 ℃ and 970 ℃ respectively, and was kept warm at rolling temperature. The influences of the rolling temperature and the holding time on the size distribution and volume fraction of inhibitor particles were observed by thermal field emission scanning electron microscopy. The precipitation amounts of Cu and Mn at the rolling surface,near surface and center of the grainoriented silicon steel under different processes were determined by inductively coupled plasma mass spectrometer. The results showed that the large size particles are the composite precipitates of CuS and MnS during the hot rolling process. The hot rolling temperature and holding time have no obvious impact on the precipitation of Mn-containing inhibitors. The lower the hot rolling temperature (970 ℃), the faster the precipitation of Copper-containing inhibitors is, but the holding time has no impact on the further precipitation of Copper-containing inhibitors, and inhibitors still remains in the precipitation state after deformation. With the extension of the holding time, the precipitation amount of copper-containing inhibitors increases after high temperature(1 100 ℃) thermal deformation/hot rolling.

Key words: deformation temperature, grain-oriented silicon steel, inhibitor, precipitation