Abstract: A process for determining the quality of a laser weld-seam, whereby a welded plate and a geometrically equivalent non-welded plate are subjected to a physical impact to generate a natural vibration frequency. The natural vibration frequency of the welded plate and the non-welded plate is then measured with an accelerometer and compared. The uniformity of the weld is then determined by the similarity between the natural vibration frequency of the welded plate and the geometrically equivalent non-welded plate.

Abstract: A process for determining the quality of a laser weld-seam, whereby a welded plate and a geometrically equivalent non-welded plate are subjected to a physical impact to generate a natural vibration frequency. The natural vibration frequency of the welded plate and the non-welded plate is then measured with an accelerometer and compared. The uniformity of the weld is then determined by the similarity between the natural vibration frequency of the welded plate and the geometrically equivalent non-welded plate.

Abstract: The method of carbo-nitriding alumina surfaces is a process for applying a carbo-nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum carbo-nitride, the oxygen being released in the form of carbon dioxide.

Abstract: The apparatus and method for controlling laser cutting through surface plasma monitoring provides real-time monitoring and control of laser cutting quality. Laser cutting of a workpiece is controlled through monitoring of surface plasma generation, particularly during a laser gas-assisted cutting process. The apparatus includes a Langmuir probe positioned adjacent the impingement point of the laser beam on the workpiece. The Langmuir probe is in communication with a signal analyzer for measuring electrical voltage generated by plasma generated by the cutting of the workpiece. A controller is provided for comparing the measured electrical voltage with a desired threshold voltage. Control signals are generated to selectively adjust output power of the laser responsive to the compared measured electrical voltage and the desired threshold voltage to minimize plasma generation.

Abstract: The energy conversion efficient thermoelectric power generator includes a p-type thermoelectric element and an n-type thermoelectric element positioned adjacent the p-type thermoelectric element defining a gap therebetween, and first and second conductive members electrically connecting opposed top and the bottom ends of the p-type and n-type thermoelectric elements, respectively. The first conductive member forms a hot junction with the top ends of the p-type and n-type thermoelectric elements, and the second conductive member forms a cold junction with the bottom ends of the p-type and n-type thermoelectric elements. The materials and dimensions of the p-type and n-type thermoelectric elements are selected such that a slenderness ratio X of each falls within the range of 0?X?1.

Abstract: The method of carbo-nitriding alumina surfaces is a process for applying a carbo-nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum carbo-nitride, the oxygen being released in the form of carbon dioxide.

Abstract: The system and method for minimizing formation of striation patterns in laser cutting provides real-time monitoring and control of laser cutting quality. Laser cutting of a workpiece is controlled through monitoring of thermal radiation generation, particularly during a laser gas-assisted cutting process. The apparatus includes an optical probe positioned adjacent the impingement point of the laser beam on the workpiece. The optical probe is in communication with a signal analyzer for measuring electrical voltage generated by thermal radiation generated by the cutting of the workpiece. A controller is provided for comparing the measured electrical voltage with a desired threshold voltage. Control signals are generated to selectively adjust output frequency of the laser responsive to the compared measured electrical voltage and the desired threshold voltage to minimize striation pattern generation.

Abstract: The energy conversion efficient thermoelectric power generator includes a p-type thermoelectric element and an n-type thermoelectric element positioned adjacent the p-type thermoelectric element defining a gap therebetween, and first and second conductive members electrically connecting opposed top and the bottom ends of the p-type and n-type thermoelectric elements, respectively. The first conductive member forms a hot junction with the top ends of the p-type and n-type thermoelectric elements, and the second conductive member forms a cold junction with the bottom ends of the p-type and n-type thermoelectric elements. The materials and dimensions of the p-type and n-type thermoelectric elements are selected such that a slenderness ratio X of each falls within the range of 0?X?1.

Abstract: Laser gas assisted nitriding of alumina surfaces is a process for applying a nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a 2 kW laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum nitride, the oxygen being released in the form of carbon dioxide.

Abstract: The method of carbo-nitriding alumina surfaces is a process for applying a carbo-nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum carbo-nitride, the oxygen being released in the form of carbon dioxide.

Abstract: The apparatus and method for controlling laser cutting through surface plasma monitoring provides real-time monitoring and control of laser cutting quality. Laser cutting of a workpiece is controlled through monitoring of surface plasma generation, particularly during a laser gas-assisted cutting process. The apparatus includes a Langmuir probe positioned adjacent the impingement point of the laser beam on the workpiece. The Langmuir probe is in communication with a signal analyzer for measuring electrical voltage generated by plasma generated by the cutting of the workpiece. A controller is provided for comparing the measured electrical voltage with a desired threshold voltage. Control signals are generated to selectively adjust output power of the laser responsive to the compared measured electrical voltage and the desired threshold voltage to minimize plasma generation.

Abstract: The energy conversion efficient thermoelectric power generator includes a p-type thermoelectric element and an n-type thermoelectric element positioned adjacent the p-type thermoelectric element defining a gap therebetween, and first and second conductive members electrically connecting opposed top and the bottom ends of the p-type and n-type thermoelectric elements, respectively. The first conductive member forms a hot junction with the top ends of the p-type and n-type thermoelectric elements, and the second conductive member forms a cold junction with the bottom ends of the p-type and n-type thermoelectric elements. The materials and dimensions of the p-type and n-type thermoelectric elements are selected such that a slenderness ratio X of each falls within the range of 0?X?1.

Abstract: Laser gas assisted nitriding of alumina surfaces is a process for applying a nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a 2 kW laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum nitride, the oxygen being released in the form of carbon dioxide.

Abstract: The method of carbo-nitriding alumina surfaces is a process for applying a carbo-nitride coating to an alumina or alumina-based composite surface. The method involves the step of applying a phenolic resin to the alumina surface in a thin, uniform film. The resin-coated alumina surface is maintained in a controlled chamber at about 8 bar pressure at a temperature of about 175° C. for about 2 hours. The surface is then heated at about 400° C. for several hours in an argon atmosphere. This converts the phenolic resin to carbon. The carbon coated alumina surface is then scanned by a laser beam while applying nitrogen under pressure. The end result is the conversion of the alumina at the surface to aluminum carbo-nitride, the oxygen being released in the form of carbon dioxide.