Patent classifications
C04B41/0036
SYSTEMS AND METHODS FOR REDUCING SURFACE OIL STREAKS ON WET EXTRUDATE BY IRRADIATION
An extrusion system (100) includes at least one sensor (102, 104) to detect localized presence of oil (701) on an exterior surface (715) or skin of wet extrudate material (714 e.g., ceramic material having a honeycomb cross-sectional shape), and at least one infrared emitting device (106, 108) configured to impinge infrared emissions on at least a portion of the exterior surface responsive to one or more sensor signals. Localized impingement of infrared emissions may reduce presence of oil streaks (701) without undue differential drying of the extrudate skin (715), and avoid surface fissures that would otherwise result in fired ceramic bodies. Separately controllable infrared emitters (502), or at least one controllable infrared blocking or redirecting element (603), may be used to impinge infrared emissions on selected areas. A humidification section (120) arranged downstream of infrared emitters (106, 108) may be used to at least partially rehydrate the wet extrudate material, if necessary.
INERT GAS-ASSISTED LASER MACHINING OF CERAMIC-CONTAINING ARTICLES
An article includes a ceramic material and features a machined surface that is characteristic of cold ablation laser machining, and the machined surface exhibits no visible oxidation. A laser machining apparatus and technique is based on cold-ablation, but is modified or augmented with an inert assist gas, to minimize deleterious surface modifications and mitigate the oxide formation associated with laser machining.
Method for machining ceramic matrix composite
A method for machining a ceramic matrix composite (CMC), the method enhancing a machining speed for the ceramic matrix composite (CMC), includes: a step of scanning an irradiated portion of a surface of a machining target material by a laser head to irradiate the irradiated portion with laser light from the laser head, and forming a deteriorated layer on the irradiated portion of the surface of the machining target material; and a step of sequentially removing the deteriorated layer by an end mill, the deteriorated layer being formed on the irradiated portion, wherein the deteriorated layer is formed by heating the irradiated portion up to a predetermined temperature by irradiation of continuous oscillation laser light, and by forming a crack by irradiation of pulsed oscillation laser light.
METHOD FOR MANUFACTURING SINTERED BODY
Disclosed is a method for manufacturing a sintered body by sintering with laser irradiation, the method for manufacturing a sintered body, including: a raw material providing step of providing a raw material containing a ceramic powder and a laser absorbing oxide having an absorption rate at a laser wavelength higher by 5% or more than that of the ceramic powder; an article forming step of forming an article formed from the raw material, an article partially including a region consisting of only the raw material, or an article formed from the raw material and formed on a base material; and a sintering step of irradiating the article with a laser to form a sintered portion.
METHOD FOR PRODUCING ALUMINUM NITRIDE SUBSTRATE, ALUMINUM NITRIDE SUBSTRATE, AND METHOD FOR SUPPRESSING OCCURRENCE OF CRACKS IN ALUMINUM NITRIDE LAYER
An object of the present invention is to provide a novel technique capable of suppressing the occurrence of cracks in an AlN layer.
The present invention is a method for manufacturing an AlN substrate, the method including: an embrittlement processing step S10 of reducing strength of a SiC underlying substrate 10; and a crystal growth step S20 of forming an AlN layer 20 on the SiC underlying substrate 10. In addition, the present invention is a method for suppressing the occurrence of cracks in the AlN layer 20, the method including the embrittlement processing step S10 of reducing the strength of the SiC underlying substrate 10 before forming the AlN layer 20 on the SiC underlying substrate 10.
INTEGRATED POLYMER-DERIVED CERAMIC THIN-FILM SENSOR PRODUCED BY LAYSER PYROLYSIS AND ADDITIVE MANUFACTURING AND FABRICATION METHOD THEREOF
An integrated polymer-derived ceramic (PDC) thin-film sensor produced by laser pyrolysis and additive manufacturing and a fabrication method thereof are provided. Using a metal component or an insulating material as a substrate, a PDC-doped composite insulating film layer with high density, high insulation, and high temperature resistance is formed by a layer-by-layer laser pyrolysis and additive manufacturing on the surface of the metal component, and a strain sensitive layer with excellent electrical conductivity is obtained by Weissenberg direct writing process PDC-doped filler sensitive grid on the composite insulating film layer and laser pyrolysis enhancing graphitization of PDC. In this way, the in situ integrated laser fabrication of highly insulating film layer, sensitive grid with excellent electrical conductivity, and metal substrate based on PDC materials is developed, which achieves the laser processing of “liquid-solid-function” transformation of PDC composites and allows the successful use thereof in strain sensing of metallic materials.
A METHOD FOR PROCESSING ZIRCONIA
- Osamu KOMEDA ,
- Takuya KONDO ,
- Toshiyuki KAWASHIMA ,
- Hirofumi KAN ,
- Nakahiro SATOH ,
- Takashi SEKINE ,
- Takashi KURITA ,
- Atsushi SUNAHARA ,
- Tomoyoshi MOTOHIRO ,
- Tatsumi HIOKI ,
- Hirozumi AZUMA ,
- Shigeki OHSHIMA ,
- Tsutomu KAJINO ,
- Yoneyoshi KITAGAWA ,
- Yoshitaka MORI ,
- Katsuhiro ISHII ,
- Ryohei HANAYAMA ,
- Yasuhiko NISHIMURA ,
- Eisuke MIURA
A problem to be solved is to provide a method for processing zirconia without producing a monoclinic crystal. The solution is a method for processing zirconia, including the step of irradiating the zirconia with a laser with a pulse duration of 10.sup.−12 seconds to 10.sup.−15 seconds at an intensity of 10.sup.13 to 10.sup.15 W/cm.sup.2.
Systems for and methods for improving mechanical properties of ceramic material
Systems for and methods for improving mechanical properties of ceramic material are provided. The system comprises a heat source for heating the ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material; a probe for mounting the ceramic material and configured to extend the ceramic material into the heat source; a plasma-confining medium and a sacrificial layer disposed between the ceramic material and the plasma-confining medium; and an energy pulse generator such as a laser pulse generator. The sacrificial layer is utilized to form plasma between the ceramic material and the plasma-confining medium. The method comprises heating ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material and subjecting the ceramic material to energy pulses via a sacrificial layer and a plasma-confining medium whereby a plasma of the sacrificial coating forms between the ceramic material and a plasma-confining medium.
Systems for and methods for improving mechanical properties of ceramic material
Systems for and methods for improving mechanical properties of ceramic material are provided. The system comprises a heat source for heating the ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material; a probe for mounting the ceramic material and configured to extend the ceramic material into the heat source; a plasma-confining medium and a sacrificial layer disposed between the ceramic material and the plasma-confining medium; and an energy pulse generator such as a laser pulse generator. The sacrificial layer is utilized to form plasma between the ceramic material and the plasma-confining medium. The method comprises heating ceramic material to a temperature greater than a brittle-to-ductile transition temperature of the ceramic material and subjecting the ceramic material to energy pulses via a sacrificial layer and a plasma-confining medium whereby a plasma of the sacrificial coating forms between the ceramic material and a plasma-confining medium.
Method for electrospinning of an ultra-high temperature composite structure
A method for forming an ultra-high temperature (UHT) composite structure includes dispensing a polymeric precursor with a spinneret biased at a first DC voltage; forming a plurality of nanofibers from the polymeric precursor; receiving the plurality of nanofibers with a collector biased at a second DC voltage different than the first DC voltage; and changing a direction of movement of the plurality of nanofibers between the spinneret and the collector with a plurality of magnets having a magnetic field by adjusting the magnetic field.