Abstract:
A heat absorbing coating having a plurality of micro-capsules each being an encapsulant shell and a heat absorbing material within the shell, and a carrier adherable to a substrate and throughout which the micro-capsules are dispersed. The heat absorbing material is preferably a phase change material and can be non-limitedly chosen from the group consisting of polyethylene, polypropylene, polywax, and combinations thereof. Shell material can be a metal such as copper, for example, or a polymer. The carrier can be a sprayable polymer mix which provides significant efficacy in uniform application to a substrate. An inventive substrate structure, such as an aircraft structure for example, has thereon the above-defined coating in an amount sufficient to absorb a sufficient amount of heat from the substrate to substantially inhibit thermal erosion in normal operating environments.
Abstract:
In accordance with the present invention, there is provided a spectral nondestructive method for evaluating substrate surface characteristics of a sample substrate. The sample substrate has a sample substrate surface and a generally visually nontransmissive sample coating disposed on the sample substrate surface. The sample coating is transmissive within a first infrared spectral wavelength range and the sample substrate is reflective within the first infrared spectral wavelength range. The method begins with directing infrared radiation from an infrared radiation source towards the coated sample substrate. Specular and diffuse infrared radiation reflected from the coated sample substrate is collected. The reflected radiation is measured as a function of wavelength in the first infrared spectral wavelength range to obtain measured reflectance data representative of the reflectance of the coated sample substrate. The measured reflectance data is compared to reference reflectance data representative of a sample substrate surface having a known physical characteristic within the first wavelength range to obtain differential data. The differential data is correlated to physical characteristics of the sample substrate surface.
Abstract:
A probe card test interface is described. The probe card test interface includes a first frame configured to support a probe card circuit card assembly (CCA). The probe card CCA is configured to contact a semiconductor wafer with one or more test probes. The first frame is also configured to support a first group of electrical contact points, the first group of electrical contact point being electrically coupled to circuitry of the probe card CCA. A second frame is coupled to a test interface CCA, where the test interface CCA includes a second group of electrical contact points. A number of actuation devices are slidably mounted on the second frame. The actuation devices have a tip member configured to engage a lip of the first frame when the corresponding actuation device is moved to an engagement position. When all of the actuation devices are in the engagement position, simultaneous actuation of the actuation devices moves the first frame toward the second frame to couple the first and second groups of electrical contact points. The first group of electrical contact points is supported by the first frame such that the probe card CCA experiences little or no deflection during actuation of the actuation devices, thereby preventing damage to the probe card CCA.
Abstract:
A heat absorbing coating having a plurality of micro-capsules each being an encapsulant shell and a heat absorbing material within the shell, and a carrier adherable to a substrate and throughout which the micro-capsules are dispersed. The heat absorbing material is preferably a phase change material and can be non-limitedly chosen from the group consisting of polyethylene, polypropylene, polywax, and combinations thereof. Shell material can be a metal such as copper, for example, or a polymer. The carrier can be a sprayable polymer mix which provides significant efficacy in uniform application to a substrate. An inventive substrate structure, such as an aircraft structure for example, has thereon the above-defined coating in an amount sufficient to absorb a sufficient amount of heat from the substrate to substantially inhibit thermal erosion in normal operating environments.
Abstract:
A microporous sheet having both acoustical and structural functionality and a process for producing the sheet. Construction of the sheet requires, first of all, providing a sheet capable of functioning as a structural element of a component. A laser device capable of producing a free electron laser beam is provided, and the free electron laser beam is directed to a surface of the sheet to penetrate the sheet at a plurality of sites and thereby form a plurality of apertures. These apertures are generally uniformly dispersed and of a size and number sufficient to enable the sheet to function as an acoustical noise suppressor while retaining capability of functioning as a structural element. Use of free electron laser technology permits formation of smooth-walled, circular or non-circular apertures tailored to exact geometry specifications controlled to a nanometer in size, and produces a microporous sheet having structural functionality while meeting acoustic requirements with clean, unclogged apertures and with low friction-to-surface and/or boundary-layer control airflow.
Abstract:
Epoxy resins modified with copolymers containing reactive groups such as -COOH are improved by vulcanizing the copolymer with an organic peroxide or sulfur.The resultant epoxy resins are useful in preparing adhesives with improved properties at elevated temperatures.
Abstract:
Plasma spraying of particulate thermotropic liquid crystalline polymers onto the surfaces of composite and metallic structures. The present plasma spray process employs a conventional direct current electric arc plasma spray gun in which an inert plasma gas is introduced, caused to swirl, and discharges as a rotating plasma flame having an exceptionally high temperature, above about 14000.degree. K, into which the particulate liquid crystal polymer is discharged for melting and propulsion onto the target surface. The target surface preferably is preheated, and the molten particles deposit and cool to form a build up of the desired thickness. Cooling is regulated by post-heating the deposit to a temperature between about 200.degree. F. and 500.degree. F.
Abstract:
In accordance with the present invention, there is provided a method of forming an acoustic attenuation chambers within a honeycomb core. The honeycomb core have a plurality of honeycomb cells having interconnected side walls. A plurality of septum layers are spaced from one another within the honeycomb cells to define acoustic attenuation chambers between the septum layers and the side walls of the honeycomb cells. Each of the septum layers have an associated ablating wavelength and is transparent to the ablating wavelengths of the other septum layers. A laser beam having a laser wavelength is directed towards the septum layers. The laser beam is selectively absorbed by a septum layer which has an associated ablating wavelength equal to the laser wavelength to ablate apertures therethrough without ablating other septum layers.
Abstract:
A microporous sheet having both acoustical and structural functionality and a process for producing the sheet. Construction of the sheet requires, first of all, providing a sheet capable of functioning as a structural element of a component. A laser device capable of producing a free electron laser beam is provided, and the free electron laser beam is directed to a surface of the sheet to penetrate the sheet at a plurality of sites and thereby form a plurality of apertures. These apertures are generally uniformly dispersed and of a size and number sufficient to enable the sheet to function as an acoustical noise suppressor while retaining capability of functioning as a structural element. Use of free electron laser technology permits formation of smooth-walled, circular or non-circular apertures tailored to exact geometry specifications controlled to a nanometer in size, and produces a microporous sheet having structural functionality while meeting acoustic requirements with clean, unclogged apertures and with low friction-to-surface and/or boundary-layer control airflow.