A micromotor for moving a body including at least one rectangular piezoelectric plate having long and short edges and first and second faces, electrodes attached to the first and second faces and a ceramic spacer attached to the center of a first one of the edges and operative to be pressed against the body. A resilient force is applied to the center of a second edge opposite the first edge, whereby the ceramic spacer is pressed against the body. At least some of the electrodes are electrified b...

A ceramic heater has a structure in which a resistance heating element mainly composed of a metal having a high melting point is embedded in a ceramic substrate. With an average grain size for component grains of the ceramic substrate taken as dB and that for component grains of the resistance heating element taken as dH, a dH/dB ratio is adjusted to not greater than 0.8.

A ceramic mixture for production of ceramic articles includes, in % weight, clay 1-64, ore selected from the group consisting of iron ore and manganese ore 30-98, and at least one metal oxide 0.1 -12.

A particulate dispersion of .alpha.-alumina, magnesium oxide and an additive selected from the group consisting of zirconium oxide, hafnium oxide and mixtures thereof, is formed into a green body and sintered in hydrogen producing a theoretically dense ceramic with improved optical transmission properties.

Cordierite ceramic consisting mainly of cordierite in crystal phase after fired and having a mean pore size of 2-50 microns and a thermal expansion coefficient of not more than 16.times.10.sup.-7 (1/.degree. C.) over the range of 25-1000.degree. C. and being produced by starting from a batch including a magnesia raw material with an average particle size of 5-150 microns.

Ceramic materials intended for cutting and consisting of aluminum oxide with additives of hard carbides or nitrides, particularly titanium carbide, have up to now, because of their sintering inertia, in general been pressure sintered to obtain satisfactory properties. According to the present invention a ceramic alloy of excellent technological properties has been formed and comprises principally Al.sub.2 O.sub.3 and hard nitrides or carbonitrides, such as TiN or Ti(C,N) in which the alloy conta...

A ceramic burner for the combustion chamber of air heaters and the like has a mixing body composed of layers of shaped ceramic bricks, the shaped bricks adjoin each other with radial flanks and engage and mutually interlock with one another by knobs or protuberances and corresponding recesses. The layers of shaped bricks are held together vertically by a ceramic bolding bar. In assembly, the mixing body has a mushroom shape wherein the upper layer shaped bricks have a larger radius than the lowe...

A free standing ceramic fireplace having a refractory base member including a hearth extension adapted to rest on a floor of a mobile home or other type residence. The fireplace has a refractory ceramic outer shell supported on the base and extending upwardly therefrom, and has a refractory ceramic, generally spherical, combustion chamber supported within the shell and closed thereto. There is a combustion air inlet to the combustion chamber extending from below the floor and a combustion gas ou...

A ceramic substrate having a convex portion formed singly or plurally on the end faces of the circumference of the substrate so as to bring the convex portions into collision with each other prior to direct collision of the substrates with each other for the purpose of effectively preventing damage due to eventual collision of the end faces of the substrates with each other or corner portions during transfer to an assembling station by an automatic feeding means such as a sloping tray.

A fast response ceramic ignitor which is particularly adapted for use with household current as a replacement for gas pilot lights, the ignitor being formed from pure lanthanum chromite, or lanthanum chromite which has been doped with combinations of niobium, magnesium, or strontium ions in quantities sufficient to provide desired electrical resistivity characteristics.