Low carbon Al2O3 - C refractory materials were prepared by "Al/Si metal incorporated,in-situ formed non-oxides " method using corundum,Al powder,Si powder and flake graphite as starting materials.High temperature strength,stress - strain relationship and thermal shock resistance of these composites were investigated. The results show that these composites possess improved high temperature strength and good thermal shock resistance. When Al addition increases from 0 to 8 mass%, correspondingly,Si addition decreases from 8 mass%to 0,hot modulus of rupture at 1 400℃increases significantly from 10.4 MPa to 32.4 MPa;the maximum strain under 6.5 MPa stress at 1 400℃decreases from 215μm to 90μm;residual strength ratio after 3 thermal shock cycles(1100℃,air quenching) decreases from 80%to 65%.This may be attributed to in-situ formation of nonoxides because Al and Si react with C,CO and N2 to form Al4C3,AlN and SiC creating strengthening and toughening effects.
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