A kind of mullite-glass coating was prepared on the surface of metal mold by thermo chemical reaction method with Al2O3

SiO2and fusible glass powder.Influences of the process parameters on the bonding strength between coating and metal matrix were investigated.The phase compositions

microstructure of the coating and element distribution were analyzed by XRD（X-ray diffraction）

SEM（scanning electron microscope）

EDS（energy dispersedly spectrometer）

respectively.Experimental results show that reaction materials after ball-milling can improve the bonding strength of coating with substrate.The bonding strength of coating with substrate is increased firstly and then decreased with the increase of the reaction time

reaction temperature and the content of fusible glass powder.The coating which formed on the surface of metal substrate at 720℃for 2his tightly combined with substrate according to the mass ratio of Al2O3

SiO2and glass powder with 2∶1∶3

and the bonding strength reaches up to 8.95MPa.The interface bonding of coating and substrate is mainly characterized by chemical and diffusional bonding.The coating is mainly composed of 3Al2O3·2SiO2

Al2SiO5

amorphous glass powder and a small amount of Al2O3

Fe3Al

FeAl

SiO2.