Effect of alumina bubbles with and without Al₂O₃ coatings on the performance of lightweight Al₂O₃‐MgAl₂O₄ refractories

Abstract

In this work, the effect of alumina bubbles with Al 2 O 3 coatings (CABs) and without coatings (ABs) on the performance of lightweight refractories was investigated. It showed that the addition of either ABs or CABs was beneficial to improve mechanical properties of refractories. The compressive strength for the specimens with 1 wt% ABs and CABs addition increased from ~50.5 to ~60.9 and ~70.2 MPa. The refractoriness under load was enhanced from ~1589 to ~1617 and ~1623°C. Furthermore, the results of three-point bending tests showed significant improvement was achieved in thermal shock resistance in terms of the value of residual strength ratio from 16% to 43% for specimens with CABs addition. Meanwhile, the results of ultrasonic pulse velocity measurement indicated that there is a good consistency between two evaluation methods. In order to achieve the trade-off between lightweight and overall performance, the introduction of CABs into lightweight refractories is feasible and effective.

Effects of Alumina Bubble Addition on the Properties of Corundum–Spinel Castables Containing Cr2O3

“…The CCS value exhibited a similar trend, which was 21.1 MPa, 75.4 MPa, 116.8 MPa, and 157.9 MPa, respectively. Overall, these results demonstrate that the physical properties of the castables can be improved by introducing a certain amount of ABs, which is similar to a previous report [28]. C increased from 11.5% to 12.7%, from 13.3% to 18.3%, from 15.3% to 19.5%, and from 13.6% to 18.8%, respectively, which may have been due to the presence of surface pores on the ABs.…”

“…The CCS value exhibited a similar trend, which was 21.1 MPa, 75.4 MPa, 116.8 MPa, and 157.9 MPa, respectively. Overall, these results demonstrate that the physical properties of the castables can be improved by introducing a certain amount of ABs, which is similar to a previous report[28].…”

Design, fabrication and properties of lightweight wear lining refractories: A review

“…Owing to the density of the surface, the lightweight refractories showed slag resistance comparable to that of the conventional dense corundum−spinel refractory [115]. Furthermore, the microstructures and properties of lightweight corundum−spinel refractories were affected by the carbon source, additives, and heat treatment [116][117][118][119][120].…”