Physical Properties of Non-Stoichiometric Sintered TiO Ceramics

Non-stoichiometric sintered TiO ceramics were produced by sintering at 1350℃ in a vacuum of 10^ Torr, starting from the mixed Powder of titanium oxide and titanium as raw materials. The TiO phase obtained was mainly cubic, but it contained complex ordered lattice structure phase only a little in the como position range between TiO_ and TiOi_. Some physical properties, such as mechanical, electrical and optical properties, and some factors governing the microstructure of the sintered bodies, such as mean crystal size, lattice strain and apparent density, were measured and related with the composition of non-stoichiometric TiO phase

ヘンイキンゾクゲンソ ノ ホウカブツ ノ コウゾウ ト ゴウセイ

The borides of transition metal elements generally display a number of unique properties including high melting point, very high hardness and strength. high thermal conductivity and relatively low thermal expansion as well as high chemical stability, and then are expected as potential candidates requiring high-temperature strength and stability under severe environments. ln this paper, crystal structure, classification, synthesis, application and preparation of these boride ceramics are reviewed

TiOショウケツタイ ノ ブツリテキ ショセイシツ ニ オヨボス MgOテンカ ノ エイキョウ

MgOを0, 1, 5, 10, 15および20 mo1%添加したTiO焼結体の物理的性質を測定し次の結果を得た.生成相はすべてNaCl型構造のTiOで,MgOはTiO相に約15%まで固溶した.MgO添加によりTiO焼結体の粒成長は抑制され,添加量の増加とともに平均粒径は減少した.MgO添加量の増加に従って焼結性は低下し,相対密度は減少した.一般に焼結体の硬さの増加に対するMgO添加の効果は大きくなく, 15%添加により無添加の最大値よりわずかに大きいビッカース硬度1350が得られた.焼結体の電気抵抗はMgO量の増加とともに増加した.これはMgOの添加による粒成長の抑制と気孔率の増加を原因とする.Some physical properties of sintered TiO doped with 0, 1, 5, 10, 15 and 20 mol% MgO were measured. All of the Ti phases obtained were identified to be NaCl type structure and solid solubility of MgO in TiO phase was assumed to be about 15%. The grain growth of TiO was suppressed by the doping of Mg0 and as the addition of MgO increased, the grain size decreased. Moreover, as the addition of MgO increased, the sinterability of TiO decreased and the relative density decreased. The effect of the addition of MgO on the hardness of TiO ceramics was not so significant. 0nly when 15 mo1% MgO was doped, the microvicker\u27s hardness was about 1350, slightly larger than that of the maximum value of TiO ceramics without any additives. The electrical resistivity of TiO ceramics increased with an increase of the addition of MgO. This is assumed to be by reasons of the suppression of grain growth and the increase of the porosity of TiO ceramics