Oxidation of TiB2 Powders below 900°C

Abstract

Oxidation studies have been performed on titanium dibor‐ide (TiB2) powders, from room temperature up to 900°C. The studies were performed at low partial pressures of oxygen, at 10 and 0. 05 ppm of O2 in argon, simulating furnace atmosphere with flowing neutral gas of medium and high purity, and in air. It has been found that titanium borate (TiBO3) is formed in these processes. It has also been revealed that the oxidation process starts below 400°C and is reversible in this low temperature range from 100° to 400°C.

Transformation behavior of yttria stabilized tetragonal zirconia polycrystal–TiB2 composites

“…25 If the low oxygen partial pressure (at the vacuum level of around 0.1 Pa) and the presence of reducing atmosphere in our hot press are taken into consideration, the oxidation of TiB 2 is expected to occur at a lower level in the investigated materials than that in an oxidizing atmosphere. 25 If the low oxygen partial pressure (at the vacuum level of around 0.1 Pa) and the presence of reducing atmosphere in our hot press are taken into consideration, the oxidation of TiB 2 is expected to occur at a lower level in the investigated materials than that in an oxidizing atmosphere.…”

Improvement in oxidation resistance of TiB2 by formation of protective SiO2 layer on surface

“…[3][4][5][6][7][8][9] The layer was severely cracked due to the thermal expansion mismatch, so that the strength after the oxidation is expected to decrease remarkably. [3][4][5][6][7][8][9] The layer was severely cracked due to the thermal expansion mismatch, so that the strength after the oxidation is expected to decrease remarkably.…”

Oxidation of monolithic TiB2 and TiB2–20wt.% MoSi2 composite at 850°C

“…The presence of B 2 O 3 could be clearly confirmed in samples oxidized up to 4 h. Minor phases like TiBO 3 , MoO 3 , and SiO 2 could not be identified, although they have been reported to form in other studies. 4,9,12 This could be due to their low volume fraction in the surface oxide volume from where the XRD information was obtained or due to their possible presence as non-crystalline phases.…”