The molten alumina produced from the reaction Fe2O3+2Al=2Fe+Al2O3 spreads on the inside wall of the steel pipe under the influence of a centrifugal force, then solidifies, so the ceramic layer has high density and smooth surface and bonds to the steel pipe.

Wear-resisting comparative table of The ceramic-lined steel composite pipe:
Sand injection test 30% Transfer test of sludge with SiO2
Material Volume diminution
Material Volume diminution
Ceamic lined
Steel pipe
0.0022 Ceamic lined
Steel pipe
Ceramic pipe
0.0025 S45C 25
Main Properties of The ceramic-lined steel composite pipe:
Item Index
Content of Alumina ≥95%
Density ≥3.5 g/cm3
Rockwell Hardness ≥80 HRA
Impact Strength ≥850 Mpa
Bending Strength  ≥290MPa
Breaking Temper ≥4.8MPa·m1/2
Coefficient of Linear Thermal Expansion 20W/m.K