Preparation of the Ceramic Hollow Balls of Aluminium Titanate-Based by Rolling-Ball Method

Abstract

Aluminium titanate - based hollow balls were prepared by using aluminum titanate, mullite and magnesia aluminate spinel as starting materials followed by the rolling-ball method. The effect of different pore-making agents (namely the amylum, flour, millet and urea) on the forming properties and the apparent qualities of the precursors of the hollow balls were investigated. The results show that the precursors of the hollow balls own both good forming properties and apparent qualities when using the amylum as pore-making agent; an appropriate heat treatment was carried out on the above precursors, and the obtained hollow balls have particle size of 5 mm, aperture diameter of 3 mm and wall thickness of 1 mm; the average compressive strength of the hollow balls reaches 15.0 N. Since this method is very simple and effective for preparation of the hollow balls, it may provide a new approach for preparation of high performance heat insulation-porous materials.

Synthesis of ZrO2-Al2O3 Composite Beads by Wet Titration Technology

“…1) When the ceramic beads are dense and without pores, the measured bulk density value of the ceramic beads will be close to the theoretical density value. From the literatures, the tested bulk density value of zirconia beads using the conventional rolling process is generally below 6.0 g/cm 3 [5][6][7][8], and the tested bulk density value of E Sample is 5.91 g/cm 3 . It can be seen in the literature that there are some defects and pores in the traditional rolling method, which leads to the density lower than the theoretical density [7].…”

“…From the literatures, the tested bulk density value of zirconia beads using the conventional rolling process is generally below 6.0 g/cm 3 [5][6][7][8], and the tested bulk density value of E Sample is 5.91 g/cm 3 . It can be seen in the literature that there are some defects and pores in the traditional rolling method, which leads to the density lower than the theoretical density [7]. The tested bulk density value of the A Sample prepared with the new method is 6.05 g/cm 3 , which is higher than E Sample.…”

“…In recent years, the ZrO 2 -Al 2 O 3 composite materials which include the advantages of high toughness characteristics inherited from zirconia and high hardness characteristics inherited from alumina have been widely used and researched [1][2][3][4][5]. However, the conventional rolling process to prepare the zirconia, alumina, ZrO 2 -Al 2 O 3 composite beads is by grinding zirconia and alumina powder, granulating and rolling them to form beads [6][7]. The main defects of the prepared beads using this method are containing many pores, large size of grains, low crushing load and small hardness characteristics, etc.…”

“…By doping with larger ions such as Y 3+ , Er 3+ , or Ce 4+ , the cubic structure of ZrO 2 can be stabilized at room temperature [8] In this work, based on wet titration technology, an innovative method to prepare the ZrO 2 -Al 2 O 3 composite beads is proposed. The ZrO 2 -Al 2 O 3 composite beads are prepared by sol preparation, titration molding process, organic compound discharging and sintering [5][6][7][8]. From the test results, it can be seen that alumina grains are evenly distributed in the beads.…”

Synthesis of yttria stabilized ZrO₂–Al₂O₃ composite beads by wet titration technology

“…1)5) The conventional rolling process to prepare the zirconia, alumina, ZrO 2 Al 2 O 3 composite beads is by grinding zirconia and alumina powder, granulating and rolling them to form beads, then obtain beads by sintering at high temperature. 6), 7) The main defects of the beads prepared by this method are containing many pores, large size of grains, low crushing load and small hardness characteristics, etc.…”