Evolution of surface morphology and internal microstructure of steel billet surface iron oxide after high pressure water descaling treatment
Steel billets were heated under different temperature and time conditions.After being discharged from the furnace the billets were treated using high pressure water to remove surface oxide.Then,the mor-phology of the billet surface iron oxide scale and its internal microstructure were observed by means of optical microscope and scanning electron microscope analyses.After descaling,the composition of the billet surface oxide phase was analyzed by using XRD analysis.The results show that a layer of iron oxide scale remains on the surface of the billet after descaling,and the composition of the oxide phase depends on the heating temper-ature and the holding time.At low temperatures and short holding times,the residual oxide scale consists of el-ementary Fe.Increasing the heating temperature and prolonging the holding time lead to the situation that the surface of the steel matrix is completely oxidized into Fe3O4and Fe2O3.Long time and high temperature heat-ing of the billets in the furnace results in problems such as coarser residual iron oxide grains,overheating of the steel matrix,oxidation of the grain boundary and decarburization,etc.The higher the heating temperature and the longer the heating time,the more serious the oxidation loss is.
NETL
NSTL
万方数据
维普
