摘要:
Piezoelectric PZT-polymer composites of 1-3 and 1-3-0 connectivity are trversely reinforced with glass fibers to increase the hydrostatic piezoelectric charge and voltage coefficients (d.sub.h and g.sub.h) for possible use in hydrophone applications. These composites consisted of a foamed (with porosity) or non-foamed (no porosity) polymer matrix with PZT rods aligned parallel to the poling direction and glass fibers in the remaining two transverse directions. Because of the small percentage of PZT required, these composites have densities near that of water, and much lower dielectric constants than solid PZT, resulting in large increases in the hydrostatic piezoelectric voltage coefficient g.sub.h. By increasing the d.sub.h and g.sub.h coefficients, the d.sub.h g.sub.h product, used as the figure of merit, is greatly enhanced.
摘要:
Composites of lead zirconate titanate (PZT) and inactive polymers with 3-1 and 3-2 patterns and a method of fabrication thereof are described. Fabrication is accomplished by drilling holes in sintered PZT blocks and filling the holes with epoxy or some other inactive polymer. The influence of hole size and volume fraction PZT on the hydrostatic properties of the composite is evaluated. By decoupling the piezoelectric coefficients d.sub.33 and d.sub.31 in the composite, the hydrostatic coefficients are greatly enhanced.
摘要:
A process for producing ultra-fine particles of calcia-stabilized zirconia in which a precursor mixture (which contains from about 80 to about 96 mole percent of zirconium ion, from about 20 to about 4 mole percent of calcium ion, a nitrogen-containing fuel, and a solvent) is dried and then subjected to a temperature of from about 275 to about 750 degrees centigrade and an atmosphere with a relative humidity of less than about 60 percent, thereby causing the dried particles to react in a vigorous manner and to form a combusted powder.
摘要:
A process for producing ultra-fine ceramic particles in which droplets are formed from a ceramic precursor mixture containing a metal cation, a nitrogen-containing fuel, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen containing fuel. The nitrogen-containing fuel contains at least three nitrogen atoms, at least one oxygen atom, and at least one carbon atom. The ceramic precursor mixture is dried to remove at least 85 weight percent of the solvent, and the dried mixture is then ignited to form a combusted powder.
摘要:
There is disclosed a process for preparing a thallium-containing superconductive composition. In the first step of the process, a mixture of an inorganic salt (such as potassium chloride) and a powder compositon is provided; the powder composition contains at least three separate compounds which, in combination, correspond to the stoichiometry of the super-conductor to be produced. This mixture is then charged to a closed container, raised to a temperature of from 800-959 degrees Centigrade, and heated for from about 1 to about 12 hours; thereafter, it is cooled to a temperature of 600 degrees Centigrade at a rate of at least 300 degrees Celsius per hour.
摘要:
A process for producing a sintered body from untra-fine superconductive particles. In the first step of this process, a ceramic precursor material containing yttrium, barium and copper cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided; the nitrogen-containing material contains at least three nitrogen atoms, at least one oxygen atom, and at least one carbon atom. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere. A green body is formed from the calcined particles which is subjected to temperature to form a sintered body.
摘要:
A process for producing ultra-fine barium hexaferrite particles. In the first step of this process, a ceramic precursor material containing barium and trivalent ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.
摘要:
An electrical circuit containing novel piezoresistive sensor is disclosed. The sensor is connected to a source of direct current, and a manometric pressure of at least about 15 p.s.i.g. is applied to the sensor.
摘要:
A process for producing ultra-fine yttrium-iron-garnet particles. In the first step of this process, a ceramic precursor material containing yettrium and ferric cations, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.
摘要:
A process for producing ultra-fine barium titanate particles. In the first step of this process, a ceramic precursor material containing a metal cation, a nitrogen-containing material, a solvent, and an anion capable of participating in an anionic oxidation-reduction reaction with the nitrogen-containing material, is provided; the nitrogen-containing material contains at least three nitrogen atoms, at least one oxygen atom, and at least one carbon atom. In the second step of the process, droplets of such ceramic precursor material are formed. In the third step of the process, the droplets are dried until particles which contain less than about 15 weight percent of solvent are produced. In the fourth step of this process, such particles are ignited in an atmosphere which contains substantially less than about 60 weight percent of the solvent's saturation value in such atmosphere.