Abstract: An additive manufacturing system, method of manufacturing, and fabricated part. The system uses a material joining laser system to join together foil sheets to form a metal part. The material joining laser system can be configured to join adjacent foil sheets together in a substantially uniform manner. The manufacturing system also includes a material removal system that removes material from selected locations of the foil sheets to shape the foil sheets to correspond with selective slices of the part. The material removal system can be a laser system, such as a laser system configured to remove material from a foil sheet without removing material from an underlying layer. One embodiment involves the manufacture of amorphous alloy components.

Abstract: An additive manufacturing system, method of manufacturing, and fabricated part. The system uses a material joining laser system to join together foil sheets to form a metal part. The material joining laser system can be configured to join adjacent foil sheets together in a substantially uniform manner. The manufacturing system also includes a material removal system that removes material from selected locations of the foil sheets to shape the foil sheets to correspond with selective slices of the part. The material removal system can be a laser system, such as a laser system configured to remove material from a foil sheet without removing material from an underlying layer. One embodiment involves the manufacture of amorphous alloy components.

Abstract: A system comprises a working laser beam, a sensing laser beam, first and second optical elements, an optical sensor, an aperture and a controller. The first optical element generates a coaxial beam from the working laser beam and the sensing laser beam. The second optical element focuses the coaxial beam onto a workpiece, such that the working laser beam machines the workpiece and the sensing laser beam reflects from the workpiece. The optical sensor senses an intensity of the reflected sensing beam. The aperture determines a focus position by translating along the reflected sensing beam, such that the reflected intensity is maximized. The controller determining a machining parameter of the working laser beam, based on the focus position.

Abstract: A system comprises a working laser beam, a sensing laser beam, first and second optical elements, an optical sensor, an aperture and a controller. The first optical element generates a coaxial beam from the working laser beam and the sensing laser beam. The second optical element focuses the coaxial beam onto a workpiece, such that the working laser beam machines the workpiece and the sensing laser beam reflects from the workpiece. The optical sensor senses an intensity of the reflected sensing beam. The aperture determines a focus position by translating along the reflected sensing beam, such that the reflected intensity is maximized. The controller determining a machining parameter of the working laser beam, based on the focus position.

Abstract: The bio-sample (e.g., a live cell) is labeled with a proper number of nanoparticles. Each nanoparticle is pre-co-doped with a controlled ratio of fluorophore donors and acceptors. Two laser pulses are applied to the bio-sample. The first laser pulse has a center wavelength near the peak of absorption spectrum of acceptors. The intensity of first laser pulse is adjusted such that FRET saturation occurs near the center of the focal spot. The focal spot of the first laser pulse is a diffraction-limited Airy disk that has the highest laser intensity in the center of the focal spot. The second laser has a center wavelength in the emission spectrum of acceptors and with a uniform intensity distribution throughout the focal spot. The fluorescence emission from acceptors after two laser pulses is from an area that is smaller than the diffraction-limited focal spot. Hence, a higher than diffraction-limit resolution is achieved.

Abstract: An article suitable for metallurgical bonding having a first part having a lower surface, and a second part having an upper surface is disclosed. The lower surface of the first part is disposed at the upper surface of the second part to provide for a faying surface thereat. The faying surface has a plurality of channels having a depth equal to or greater than about 1 micron and equal to or less than about 1000 microns. The article is suitable for metallurgical bonding at the faying surface.

Abstract: According to the invention a hollow cylindrical shank of electrically conducting metal is connected to a resistance welder. A coolant supply tube passes through the shank and has an interior coolant supply passage. The coolant supply tube has an outer diameter less than the inner diameter of the hollow cylindrical shank. A weld cap seats on the shank and has a cap tip and a cap skirt that depends from the cap tip and is attached to the shank. An underside of the cap tip faces the shank and the supply tube. A coolant receiving bore formed into the underside of the weld cap extends into the cap tip to receive the coolant supply tube part way into the bore. The bore formed into the underside of the cap tip defines a bore sidewall that provides added area of heat transfer contact between the coolant and the cap tip.

Abstract: The bio-sample (e.g., a live cell) is labeled with a proper number of nanoparticles. Each nanoparticle is pre-co-doped with a controlled ratio of fluorophore donors and acceptors. Two laser pulses are applied to the bio-sample. The first laser pulse has a center wavelength near the peak of absorption spectrum of acceptors. The intensity of first laser pulse is adjusted such that FRET saturation occurs near the center of the focal spot. The focal spot of the first laser pulse is a diffraction-limited Airy disk that has the highest laser intensity in the center of the focal spot. The second laser has a center wavelength in the emission spectrum of acceptors and with a uniform intensity distribution throughout the focal spot. The fluorescence emission from acceptors after two laser pulses is from an area that is smaller than the diffraction-limited focal spot. Hence, a higher than diffraction-limit resolution is achieved.

Abstract: According to the invention a hollow cylindrical shank of electrically conducting metal is connected to a resistance welder. A coolant supply tube passes through the shank and has an interior coolant supply passage. The coolant supply tube has an outer diameter less than the inner diameter of the hollow cylindrical shank. A weld cap seats on the shank and has a cap tip and a cap skirt that depends from the cap tip and is attached to the shank. An underside of the cap tip faces the shank and the supply tube. A coolant receiving bore formed into the underside of the weld cap extends into the cap tip to receive the coolant supply tube part way into the bore. The bore formed into the underside of the cap tip defines a bore sidewall that provides added area of heat transfer contact between the coolant and the cap tip.

Abstract: An article suitable for arc-welded metallurgical bonding having a first part having a lower surface, and a second part having an upper surface is disclosed. The lower surface of the first part is disposed at the upper surface of the second part to provide for a faying surface thereat. The faying surface has a plurality of channels with a depth equal to or greater than about 1 micron and equal to or less than about 1000 microns. The article is suitable for arc-welded metallurgical bonding at the faying surface. The plurality of channels has a repetitive pattern of channels arranged along a path of the faying surface in a direction of the metallurgical bonding action.

Abstract: A method of improving weld quality between aluminum members by slowing the rate of solidification of a molten weld trough into solidified material. Upper and lower aluminum members are positioned together in contact between facing surfaces thereof to expose a first outer surface of the upper aluminum member to laser irradiation. A welding laser beam is moved in a path over the first outer surface, wherein the welding laser beam has an energy and width to progressively melt a trough of molten metal to a depth through the upper aluminum member and into the lower aluminum member. The molten metal in the trough has a void filled with gas, and the molten metal re-solidifies into re-solidified metal after the passage of the welding laser beam. An area in and around the trough is heated to slow the rate of solidification of the molten metal into the re-solidified metal, thereby preventing entrainment of the gas within the re-solidified metal.

Abstract: In laser welding of metallic workpieces, the energetic beam is moved over the workpiece surface to form a pool of molten weld metal that quickly solidifies behind the advance of the laser into a weld nugget. The laser beam produces a keyhole of plasma-containing vapor within the molten pool. Weld nugget porosity, due to entrapment of the vapor, is minimized by continually sensing radiation from the molten metal pool to determine pool depth and width and then controlling laser power and speed to continually produce a weld metal pool wide enough for the liquid to fully expel the vapor and solidify into a pore free nugget.

Abstract: An article suitable for metallurgical bonding having a first part having a lower surface, and a second part having an upper surface is disclosed. The lower surface of the first part is disposed at the upper surface of the second part to provide for a faying surface thereat. The faying surface has a plurality of channels having a depth equal to or greater than about 1 micron and equal to or less than about 1000 microns. The article is suitable for metallurgical bonding at the faying surface.

Abstract: An article suitable for arc-welded metallurgical bonding having a first part having a lower surface, and a second part having an upper surface is disclosed. The lower surface of the first part is disposed at the upper surface of the second part to provide for a faying surface thereat. The faying surface has a plurality of channels with a depth equal to or greater than about 1 micron and equal to or less than about 1000 microns. The article is suitable for arc-welded metallurgical bonding at the faying surface. The plurality of channels has a repetitive pattern of channels arranged along a path of the faying surface in a direction of the metallurgical bonding action.

Abstract: A double pulse welding current method is disclosed for the generation and transfer of droplets of welding metal from an electrode wire to a workpiece in an arc welding process. A suitable background direct current level is specified to deliver a desired number of droplets to the weld site. During each cycle of droplet formation and transfer, a first increased current pulse is applied to the electrode and arc to generate a droplet on the tip of and electrode and then a second further increased current pulse is applied to timely separate the droplet from the electrode for transport in the arc to the workpiece. This double-pulse current application reliably produces one droplet per cycle of pulses to deliver a specified number of droplets to the weld site for improved weld quality and reduced spatter or waste of weld metal.

Abstract: A method of improving weld quality between aluminum members by slowing the rate of solidification of a molten weld trough into solidified material. Upper and lower aluminum members are positioned together in contact between facing surfaces thereof to expose a first outer surface of the upper aluminum member to laser irradiation. A welding laser beam is moved in a path over the first outer surface, wherein the welding laser beam has an energy and width to progressively melt a trough of molten metal to a depth through the upper aluminum member and into the lower aluminum member. The molten metal in the trough has a void filled with gas, and the molten metal re-solidifies into re-solidified metal after the passage of the welding laser beam. An area in and around the trough is heated to slow the rate of solidification of the molten metal into the re-solidified metal, thereby preventing entrainment of the gas within the re-solidified metal.

Abstract: An article suitable for laser-welded metallurgical bonding, the article having a first part having a lower surface, and a second part having an upper surface is disclosed. The lower surface of the first part is disposed at the upper surface of the second part to provide for a faying surface thereat. The faying surface has a plurality of channels with a depth equal to or greater than about 1 micron and equal to or less than about 1000 microns. The article is suitable for laser-welded metallurgical bonding at the faying surface. The plurality of channels has a repetitive pattern of channels arranged along a path of the faying surface in a direction of the metallurgical bonding action.