摘要:
This active brazing serves to braze ceramic parts or single crystals or metal parts or to braze ceramic parts to single crystals or ceramic parts or single crystals to metal parts. In addition to the zirconium-nickel alloy, which is composed of 70 atom % to 85 atom % zirconium and 15 atom % to 30 atom % nickel, it contains titanium. In an apparatus for fabricating a foil (6) from this ternary active-brazing alloy by melt spinning which has a uniform thickness and two surfaces that are as smooth as possible, the alloy, after being melted by high-frequency heating in a cylindrical crucible (1) made completely of a high-temperature-resistant and highly thermally conductive nonmetallic material, particularly of high-density graphite or of boron nitride, is forced through an opening (3) in the bottom of the crucible onto a metal drum (5) of high thermal conductivity rotating at a high circumferential speed, on which the liquid alloy solidifies at a cooling rate on the order of 10.sup.3 to 10.sup.6 .degree. C./s. A product made using this ternary active brazing is a pressure sensor (10) having a substrate (12) and a diaphragm (11) of ceramic, particularly alumina ceramic, preferably with a purity of 96 wt.%, which are thermally joined around the periphery in a defined spaced relationship (d) and parallel to each other by means of the active brazing, e.g., by means of a preform (20) made therefrom, thus forming a chamber (13).
摘要:
The pressure sensor consists of a substrate and a diaphragm joined together around the periphery so as to form a chamber. The surface of the diaphragm facing away from the substrate is exposed to a medium whose pressure is to be measured. To protect the diaphragm against corrosion or abrasion, the diaphragm surface exposed to the medium is covered with a layer of silicon carbide, preferably by chemical vapor deposition.
摘要:
A thin-film humidity sensor for measuring the absolute humidity having a base electrode, a moisture-sensitive dielectric layer and a top electrode is formed at the end face of an electrically insulating bushing body by the thin-film technique. The connecting conductors are led through the bushing body and terminate in contact areas which are ground plane and polished together with the end face of the bushing body. The metal layers forming the electrodes are so shaped on application, preferably by means of perforated masks, that they each cover the contact area of the associated connecting conductor and are electrically connected thereto. The bushing body is inserted into a sleeve of a highly alloyed nickel-molybdenum compound and connected thereto in pressure-resistant manner.
摘要:
A pressure sensor includes a platform and an elastic measuring membrane, which is joined with a surface of the platform to form a measuring chamber sealed closed at the edge, wherein the platform and/or the measuring membrane comprise ceramic, glass or a single crystal material, the measuring membrane has at least a first electrode, which faces the surface of the platform, the surface of the platform has at least a second electrode, which faces that of the measuring membrane. The capacitance between the first electrode and the second electrode is a measure for the pressure to be measured; wherein additionally at least one of the first and second electrodes comprises a conductive layer, which contains metal and glass, and wherein the metal comprises at least two noble metal elements.
摘要:
An elastic ceramic body and a pressure sensor. The elastic ceramic body comprises: a base body of an elastic ceramic material; and a cover layer, which covers at least one section of a surface of the base body, wherein the cover layer is of a material other than that of the base body, and the cover layer comprises microcrystalline A12O3 (corundum). The cover layer is preferably prepared in a sol gel process. The pressure sensor, comprises: a disk-shaped measuring membrane, which is embodied as an elastic ceramic body according to the above definition; and at least one membrane support body, on which the measuring membrane is connected at its edge region along an encircling joint to form a pressure-tight measuring chamber between the membrane support body and the measuring membrane.
摘要:
A pressure transducer, including a housing having a housing axis and a measuring cell chamber defined in the housing. The measuring cell chamber is exposable to a pressure via an opening. The opening is surrounded by an annular, first sealing surface. A pressure measuring cell having a second sealing surface facing towards the opening, and a support surface facing away from the sealing surface sealing ring; and a clamping apparatus, which engages the housing are provided. The pressure measuring cell and the sealing ring are clamped by means of an axial clamping force in such a manner between the clamping apparatus and the first sealing surface, that the sealing ring is arranged pressure-tightly between the first sealing surface and the second sealing surface. The pressure transducer further includes a misalignment accommodating arrangement, which includes a first transmission body, which faces toward the opening, and a second transmission body, which is facing away from the opening. The axial clamping force is transmitted through the misalignment accommodating arrangement, from the clamping apparatus to the pressure measuring cell, and the first transmission body is tiltable relative to the second transmission body about two mutually perpendicular axes.
摘要:
A pressure sensor including: A pressure measuring cell having an end face loadable with the medium; a housing having a media opening and a ring-shaped, axial bearing surface, which surrounds the media opening; a clamping apparatus; and a ring-shaped sealing arrangement. The pressure measuring cell is positioned in the housing and the sealing arrangement is positioned between the bearing surface and the end face, and the sealing arrangement, as well as the pressure measuring cell, are axially clamped between the bearing surface and the clamping apparatus. The sealing arrangement includes, a decoupling ring, as well as a first and a second, ring-shaped sealing element. The first sealing element lies against the end face, the second sealing element lies against the bearing surface, and the decoupling ring is axially clamped between the first and the second sealing elements.
摘要:
For minimizing the span error of a pressure sensor having an essentially cylindrical platform and a measuring membrane joined to an end face of the platform, with the pressure measuring cell being axially clamped between an elastic sealing ring, which bears against the membrane-bearing end face of the pressure measuring cell, and a support ring, which bears against the rear face of the pressure measuring cell, the dimensions of the support ring are coordinated with the dimensions of the sealing ring and pressure measuring cell such that a radial deformation of the membrane-bearing end face caused by the axial clamping of the pressure measuring cell is sufficiently small that the span error of the pressure sensor arising from a reduction of the axial clamping force by at least 10% amounts to not more than about 0.02%. Additionally, arranged between the support ring and a clamping ring is a stiff decoupling element, which minimizes the temperature hysteresis of the span. The geometry of the support ring and the decoupling element is determined iteratively by means of FEM.
摘要:
For minimizing the span error of a pressure sensor having an essentially cylindrical platform and a measuring membrane joined to an end face of the platform, wherein the pressure measuring cell is axially clamped between an elastic sealing ring, which bears against the membrane-containing, end face of the pressure measuring cell, and a support ring, which supports the measuring cell on the rear side thereof, the dimensions of the support ring are matched to the dimensions of the sealing ring and the pressure measuring cell in such a way that a radial deformation of the membrane-containing end face resulting from the axial clamping of the pressure measuring cell is sufficiently small that the span error of the pressure sensor because of a reduction of the axial clamping force by a least 10% amounts to not more than 0.02%. The geometry of the support ring is determined iteratively by means of the FEM.
摘要:
A pressure sensor for measuring a pressure includes a pressure chamber; and a deformation body, which can be exposed to a medium under pressure, and which, additionally, at least partially bounds the pressure chamber and seals such pressure-tightly from the medium; wherein the walls of the sensor chamber have a hydrophobic coating, which was applied by gas and/or vapor phase deposition. The hydrophobic coating preferably includes a silane. Especially suited are silanes having one or more hydrophobic groups R and one or more anchoring groups X. Especially preferred are: R—Si—X3, R1R2—Si—X2, R1R2R3—Si—X. The hydrophobic group R is preferably an alkyl, perfluoroalkyl, phenyl or perflurorophenyl group. The anchoring group X is preferably an —OH (silanol), —X (halide, e.g. —Cl), —OR (ester, e.g. —OCH3), —NH2 (amine), or —SH (Mercaptosilane). Additionally, aliphatic or cyclic silazanes —Si—NH—Si—, e.g. hexamethyldisilazane, can be used. Likewise suitable are compounds of the type Ry—Me—Xz, with Me=e.g. Zr, Ti.
摘要翻译:用于测量压力的压力传感器包括压力室; 以及变形体,其可以在压力下暴露于介质,并且另外至少部分地限定压力室并且与介质如此压力地密封; 其中传感器室的壁具有通过气相和/或气相沉积施加的疏水涂层。 疏水涂层优选包括硅烷。 特别优选的是具有一个或多个疏水基团R和一个或多个锚定基团X的硅烷。特别优选的是:R-Si-X 3,R 1 R 1, 2 -Si-X 2,R 1 R 2 R 3 -Si-X。 疏水性基团R优选为烷基,全氟烷基,苯基或全氟苯基。 锚定基团X优选为-OH(硅烷醇),-X(卤化物,例如-Cl),-OR(酯,例如-OCH 3),-NH 2(胺)或-SH(巯基甲硅烷)。 另外,脂族或环状硅氮烷-Si-NH-Si-,例如 六甲基二硅氮烷。 同样合适的是类型R a-Me-X z z的化合物,其中Me = Zr,Ti。