Effects Of Fine Powder And Alumina Additions On Structures And Properties Of High Chrome Bricks

This paper studies the Effects of fine powder and Alumina Additions on structures andproperties of high chrome bricks from two aspects. On one hand，it is Matrix section. The highchrome bricks were separately prepared by Fused chromium oxide powder、chromium oxidegreen、-Al2O3、Monoclinic zirconia，sintered at the atmosphere with weak reducing，andthe characteristics of cold MOR, hot MOR, thermal shock resistance and microscopic structureshad been investigated；on the another hand，it is the particulate fraction. The Fused chromiumoxide powder were replaced by Al-Cr solid solution and studied the Room temperatureproperties、high-temperature behaviors and Thermal shock resistance of the high chromebricks on the different addition of alumina. The results are as follows:(1)With the increasing amount of chromium oxide green of high chrome bricks from0percent to8percent，the characteristics of cold MOR, hot MOR, thermal shock resistanceIncreases first and then decreases，which indicate that additions of chromium oxide green playa promoting role in the sintering of high chrome bricks in a certain rang and excessive additionwill reduce material properties.(2)With the increasing of alumina from0percent to8percent，the characteristics of coldMOR, hot MOR, thermal shock resistance improve significantly，Performance improvement ison the rise below6percent and The performance of the specimens decreased with More than6%additions，which indicate that The6%is the best content of alumina powder.(3)With the matrix zirconia powder addition increasing from0%to8%， thecharacteristics of cold MOR, hot MOR, thermal shock resistance Increases first and thendecreases. The hot MOR, thermal shock resistance are the best with4%addition. The hot MORimproves from25.5MPa to34.6MPa and the residual strength improves from10.2MPa to18.4MPa.(4) The Fused chromium oxide powder were replaced by Al-Cr solid solution. The resultshows that introduction of alumina powder does well to improve the characteristics of cold MOR, hot MOR, thermal shock resistance and microscopic structures of high chrome bricks.with2%additions，the improvement of performance are most obvious. This ameliorative trenddecreases with the increase of amount of alumina with more than2%.the properties of highchrome bricks reduce in the alumina micro powder after8%. Taking all factors into account，the best addition is6%.