Abstract:
The composition protective coatings on the surface of carbon steel crucible were prepared by aluminizing and high temperature chemical reaction. The relations between the thickness of reaction product layer and reaction temperature and time were investigated. The microstructures and phase composition of the coating layer were investigated by means of optics microscope and XRD. The experimental results show that the thicknesses of reaction product layers increase with the reaction temperature and time increasing. The composition coatings are composed of transition layer and reaction product layer. The constitution of transition layer are Fe
3Al and small amount of Fe
2Al
5, Fe
14Al
86 and Al
2O
3. The reaction product layer are consisted of TiB
2, MgO and small amount of Mg
2TiO
4, Mg
2B
2O
5, Fe
3Al, FeAl and Ti
2B
5.