Development of additive technological method for gas-powder laser surfacing process

The methods of additive techniques of layer-by-layer laser agglomeration of powder materials at a direct injection and mechanical powder feed are considered. A method for layer-by-layer surfacing with a scanning laser beam is offered. The paths of scanning on a line, ellipse and a circle are analyzed. Samples are processed and investigations on an influence of a processing velocity and the paths of scanning upon geometrical adjectives of layers obtained are carried out. The investigation results obtained allowed drawing a conclusion of the optimality of a scanning path of a laser beam on an ellipse, on geometrical adjectives and a coefficient of powder use.

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Localized Die Metallization Damage Induced During Laser-Marking of a Semiconductor Package

ISTFA 2007: Conference Proceedings from the 33rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2007p0226 ◽

2007 ◽

Author(s):

Paul Eric B. Parañal

Keyword(s):

Laser Beam ◽

Direct Interaction ◽

Silica Spheres ◽

Layer By Layer ◽

Laser Marking ◽

Molding Compound ◽

Molding Material ◽

Die Surface ◽

Passivation Layers ◽

Propagation Medium

Abstract This paper presents a new fail mechanism for laser-marking induced die damage. Discovered during package qualification, silica spheres – commonly used as fillers in the molding material, was shown to act as a propagation medium that promote the direct interaction of the scribing laser beam and the die surface. Critical to the understanding of the fail mechanism is the deprocessing technique devised to allow layer by layer examination of the metallization and passivation layers in an encapsulated silicon die. The technique also made possible the inspection of the molding compound profile directly on top of the affected die area.

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Communication System of Realtime Two-Dimensional Position Data with Scanning Laser Beam

10.22260/isarc1996/0066 ◽

1996 ◽

Author(s):

S. Tonaki ◽

T. Takada

Keyword(s):

Laser Beam ◽

Communication System ◽

Scanning Laser ◽

Two Dimensional ◽

Position Data

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Fracture Toughness of Hybrid Components with Selective Laser Melting 18Ni300 Steel Parts

Applied Sciences ◽

10.3390/app8101879 ◽

2018 ◽

Vol 8 (10) ◽

pp. 1879 ◽

Cited By ~ 6

Author(s):

Luis Santos ◽

Joel de Jesus ◽

José Ferreira ◽

José Costa ◽

Carlos Capela

Keyword(s):

Fracture Toughness ◽

Selective Laser Melting ◽

Compact Tension ◽

Powder Materials ◽

Layer By Layer ◽

Laser Melting ◽

Conventional Steel ◽

Scan Rate ◽

Aisi H13 ◽

3D Printed

Selective Laser Melting (SLM) is currently one of the more advanced manufacturing and prototyping processes, allowing the 3D-printing of complex parts through the layer-by-layer deposition of powder materials melted by laser. This work concerns the study of the fracture toughness of maraging AISI 18Ni300 steel implants by SLM built over two different conventional steels, AISI H13 and AISI 420, ranging the scan rate between 200 mm/s and 400 mm/s. The SLM process creates an interface zone between the conventional steel and the laser melted implant in the final form of compact tension (CT) samples, where the hardness is higher than the 3D-printed material but lower than the conventional steel. Both fully 3D-printed series and 3D-printed implants series produced at 200 mm/s of scan rate showed higher fracture toughness than the other series built at 400 mm/s of scan rate due to a lower level of internal defects. An inexpressive variation of fracture toughness was observed between the implanted series with the same parameters. The crack growth path for all samples occurred in the limit of interface/3D-printed material zone and occurred between laser melted layers.

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Scanning Laser Ophthalmoscopy

Güncel Retina Dergisi (Current Retina Journal) ◽

10.37783/crj-0004 ◽

2017 ◽

pp. 18-21

Keyword(s):

Light Intensity ◽

Laser Beam ◽

Imaging Technique ◽

Morphological Changes ◽

Imaging Techniques ◽

Tissue Level ◽

Scanning Laser ◽

Scanning Laser Ophthalmoscopy ◽

Imaging Device ◽

Scanning Laser Microscopy

The aim of retinal imaging techniques is visualization of morphological changes at the cellular and tissue level. Various techniques are used for this purpose. The scanning laser ophthalmoscopy (SLO), a retinal optical imaging device based on standard scanning laser microscopy is an imaging technique that scans the fundus with a highly collimated narrow laser beam and measures the backscattered light intensity. Here, progress on developing SLO instruments and their applications in ophthalmology are reviewed.

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Comparison of Activation Technologies Powder ECP-1 for the Synthesis of Products Using SLS

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.756.220 ◽

2015 ◽

Vol 756 ◽

pp. 220-224 ◽

Cited By ~ 8

Author(s):

E.V. Babakova ◽

A.V. Gradoboev ◽

A.A. Saprykin ◽

E.A. Ibragimov ◽

V.I. Yakovlev ◽

...

Keyword(s):

Gamma Radiation ◽

Mechanical Activation ◽

Copper Powder ◽

Human Activities ◽

Radioactive Isotope ◽

Powder Materials ◽

Layer By Layer ◽

Structure And Properties ◽

Heavy Industry ◽

Laser Process

At present the development of methods of layer-by-layer and line-by-line synthesis of finished prototypes and functional products made of powder materials furthers introduction of these technologies into different areas of human activities from light to heavy industry and medicine. The research has been carried out to describe how gamma radiation of the Co60radioactive isotope and the mechanical activation makes an impact on the copper powder, as well as the nature of sintering by the layer-by-layer laser synthesis. The changes of the structure and properties of the powder, which generally affects the layer-by-layer laser process of products sintering, have been detected.

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