Research on Al-Cr2O3-Al2O3 Unfired Sliding Gate Performance

摘要

High performance Al-Cr2O3-Al2O3 unfired sliding gates are made from tabular corundum,white fused corundum,aluminum powder,and chromium oxide powder.Phenolic resin is used as binder.After heating treatment at 200°C ×24h,the properties of the Al-Cr2O3-Al2O3 unfired sliding gates with the different contents of chromium oxide(mass percent 3％,6％,9％,12％,15％) were examined.And their performance was compared with Al2O3-C and Al2O3-Zr2O3-C sliding gate.The results shows that the specimens which contain 6％chromium oxide powder have the best comprehensive properties,such as apparent porosity 7.2％,bulk density 3.21g/cm3,cold modulus of rupture 202MPa,hot modulus of rupture 41.1MPa.The high temperature performance is more prominent and it is about three times of Al2O3-C sliding gate (11-14MPa) and Al2O3-ZrO2-C sliding gate (13-16MPa).The plasticity phases formed during the working time of the Al-Cr2O3-Al2O3 unfired sliding gates,which can well buffer and absorb the thermal stress,plus the erosion resistance of chrome oxide,so the Al-Cr2O3-Al2O3 unfired sliding gates can replace Al2O3-C sliding gate and Al2O3-ZrO2-C sliding gate.