Your Selections

Lasers
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Committees

Events

Magazine

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Study on Effect of Laser Peening on Inconel 718 Produced by DMLS Technique

Vellore Institute of Technology-Nattudurai Navin Kumar, Aditya Chandrakant Yadav, Kumar Raja, Subramanian Prabhakaran, Chooriyaparambil Damodaran Naiju, Sivaperuman Kalainathan
  • Technical Paper
  • 2019-28-0146
To be published on 2019-10-11 by SAE International in United States
In Additive manufacturing, Direct Metal Laser Sintering (DMLS) is a rapid manufacturing technique used for manufacturing of functional component. Finely powered metal is melted by using high-energy fiber laser, by Island principle strategy that produces mechanically and thermally stable metallic component with reduced stresses, thermal gradients and at high precision. Inconel is an austenitic chromium nickel-based superalloy often used in the applications which require high strength and temperature resistant. It can retain its properties at high temperature. An attempt is made to examine the effect of laser shot peening (LSP) on DMLS Inconel 718 sample. Microstructure shows elliptical shaped structure and formation of new grain boundaries. The surface roughness of the material has been increased due to the effect of laser shock pulse and ablative nature. Macro hardness increased to 13% on the surface. Depth wise microhardness was investigated, found to be 17% increase on the sub-layer of the material due to the effect of a hardened matrix formed by precipitation hardening and grain size refinement attributed by laser shock peening. SEM analysis shows larger…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Advances in Laser Welding of Stainless Steel Alloys

BSACIST-Varun Kumar Arulvizhi, Selvakumar Alandur Somasundaram, Mohammed Haareeskhan Niyaz, Pradeep Krishna Ranganathan, Afnan Zaid Moolai, Mohamed Ashfaq Ahmed Abdulla Burhanudeen, Mohan Raj Ramu
  • Technical Paper
  • 2019-28-0056
To be published on 2019-10-11 by SAE International in United States
As a fusion welding process, Laser welding has proven to be the most promising method for joining of different materials whether it can be either a similar or dissimilar material category. However, few complications still remain unanswered in joining of materials by laser process after successful implementation of laser’s by industries and also the commercial users in previous year’s such as workpiece preparation, fixture issues, atmospheric conditions, nozzle focus on the material, etc., This article will give an elaborate survey on joining of stainless steel alloys, though there are many factors to be considered here concentration is on the metallurgical behaviour and tensile properties of weldments joined by laser welding technique, because the main criteria for a weldment is to have a coarse grain boundary distribution which may be distorted due to high heat generation during a joining process and to possess good tensile strength in order to withstand the impacts given on the weldment when it is being practically deployed in usage. The material behavior of weldment is primarily based on the process parameters…
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Improving Competitiveness of Additive Manufacturing Aerospace Serial Parts

LISI Aerospace-Maxime Gas, Alexis Rene-Corail, Sebastien Eyrignoux, Guillaume Iker, Stephane Sudre
Published 2019-09-16 by SAE International in United States
The Powder Bed Fusion technology is exploding in aerospace industry, with various parts adapted to this process. But one of the main limiting factor to use it in the aircraft industry is quantity of parts that can be manufactured per machine within a year.As a major leader in the aerospace fastener industry, LISI AEROSPACE has a long experience in reducing wasted time. Two activities are developed in this article: Decreasing production time thanks to a support structure reduction and simulationMinimizing unproductive time between two consecutive batches, thanks to manufacturing change improvement (LEAN)We took the example of a serial aircraft part, produced on the CONCEPT LASER M1 machine. With these two activities, we save 253 minutes per production. Originally, we had 4 batches per week; after these activities, we can produce 5 batches per week.
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Optical Evaluation of Directly Injected Methane Using a Newly Developed Highly Repetitive Laser Diagnostics System

Bayreuth Engine Research Center-Mirko Geiger, Lukas Schroeder, Christian Zoellner, Dieter Brueggemann
Goldlücke GmbH-Juergen Goldluecke lng
Published 2019-09-09 by SAE International in United States
Gaining detailed knowledge about the injection and mixture formation inside engines and combustion chambers during different operation modes is of major importance for improving conventional systems as well as developing new, innovative concepts. To reduce pollutants while maintaining high performance and efficiency an advanced understanding of these mechanisms is necessary. Additional challenges arise when it comes to analyzing transient engine operation and cyclic fluctuations as well as rating their contribution to the formation of emissions. This study contains the evaluations of the injection and mixture formation inside a rapid compression machine (RCM) with directly injected methane. A newly developed highly repetitive optical measurement system based on laser-induced fluorescence (LIF) is used for the quantitative visualizations of the air-fuel equivalence ratio (λ). Various operation conditions, such as different compression ratios, variations of the start of injection, variations of charge pressure as well as different injection pressures allow to evaluate influences on the mixture formation. Interpretations of the recorded images deliver a better understanding of direct injection and mixture processes under engine-like conditions as charge motion and…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

3D Meta-Optics for High-Energy Lasers

Aerospace & Defense Technology: September 2019

  • Magazine Article
  • 19AERP09_09
Published 2019-09-01 by SAE International in United States

Engineering electromagnetic fields in 3D dielectric structures to change the way components are designed and fabricated for high-energy laser (HEL) applications.

The scope of this research radically changed the way novel components are designed and fabricated for high-energy applications. This 3D Meta-Optics platform was, and is, essentially engineering the electromagnetic fields in 3D dielectric structures. The results have provided a class of transformational optical components that can be integrated at all levels throughout a high-energy laser system.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Improving Lidar - or Defeating It

Autonomous Vehicle Engineering: September 2019

Bradley Berman
  • Magazine Article
  • 19AVEP09_08
Published 2019-09-01 by SAE International in United States

The buzz at Sensors Expo pitted lidar-tech optimism against the reality of an impending shakeout.

For more than a decade, the lidar market has been led by Velodyne and its spinning towers of 64 or 128 laser beams. But the relatively high cost, delicate architecture, and beefy form factor have made it a competitive target. The growing ranks of competitors fall roughly into two camps. There are the fledgling lidar-makers with novel approaches to distance measurement, laser wavelength, and beam steering. And there are those with radar and vision systems promising lidar-level sensing capabilities at a lower cost.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Integration of Adaptive Optics Into High-Energy Laser Modeling And Simulation

Aerospace & Defense Technology: September 2019

  • Magazine Article
  • 19AERP09_08
Published 2019-09-01 by SAE International in United States

Implementing adaptive optics can substantially increase the effective range of high energy lasers used in directed energy weapons systems.

The U.S. Navy is constantly predicting future threats and contemplating new weapon technologies to counter them. One of those technologies is directed-energy (DE) weapons. Conventional weapons rely on the kinetic energy of projectiles. High-energy lasers (HELs), one type of directed-energy weapon, work in a fundamentally new way, using electromagnetic radiation to damage or destroy enemy assets.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Ultrafast Optics: Vector Cavity Lasers - Physics and Technology

Aerospace & Defense Technology: September 2019

  • Magazine Article
  • 19AERP09_10
Published 2019-09-01 by SAE International in United States

Investigating the operation of fiber lasers where the vector nature of light propagation in the laser cavity is considered.

Fiber lasers have found widespread applications in industrial material processing, scientific research and military systems due to their advantages of easy maintenance, excellent stability, compact size and low cost. One characteristic of fiber lasers, compared to other types of lasers, is that strong light is confined to propagating a long distance in a fiber core that has a very small cross-sectional area. This has the consequence that the nonlinear light interaction with the matter has a very long length. This results in the strength of all nonlinear optical processes being strongly amplified. This means that a conventionally weak, nonlinear optical effect can become significant. Therefore, apart from the practical applications, fiber lasers also constitute an ideal platform for the exploration of various complex nonlinear dynamics.

Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.
new

Aerospace & Defense Technology: September 2019

  • Magazine Issue
  • 19AERP09
Published 2019-08-29 by SAE International in United States
Air Caster Technology Safeguard Satellites During Assembly and TestingOperational Considerations for High-Reliability Interconnects in Military and Aerospace ApplicationsUnderstanding Fiber Optic Transceiver Design and Test RulesAcceleration Resistant HiK Heat SpreaderShape-Shifting Origami Could Help Antenna Systems Adapt On-the-FlyNASA Eyes GPS at the Moon for Artemis MissionsSpatiotemporal Imaging Exploiting Structured Sparsity Overcoming the conventional limits of spatiotemporal imaging by applying compressed sensing and sparse representations to reduce the amount of data acquired while maintaining high image resolution.Integration of Adaptive Optics Into High-Energy Laser Modeling And Simulation Implementing adaptive optics can substantially increase the effective range of high energy lasers used in directed energy weapons systems.3D Meta-Optics for High-Energy Lasers Engineering electromagnetic fields in 3D dielectric structures to change the way components are designed and fabricated for high-energy laser (HEL) applications.Ultrafast Optics: Vector Cavity Lasers - Physics and Technology Investigating the operation of fiber lasers where the vector nature of light propagation in the laser cavity is considered.

Virtual Biopsy Device Detects Skin Tumors

  • Magazine Article
  • TBMG-34980
Published 2019-08-01 by Tech Briefs Media Group in United States

Using sound vibrations and pulses of near-infrared light, a new “virtual biopsy” device can quickly determine a skin lesion's depth and potential malignancy without using a scalpel. The first-of-its-kind experimental procedure, called vibrational optical coherence tomography (VOCT), creates a 3D map of the legion's width and depth under the skin with a tiny laser diode. It also uses soundwaves to test the lesion's density and stiffness since cancer cells are stiffer than healthy cells. An inch-long speaker applies audible soundwaves against the skin to measure the skin's vibrations and determine whether the lesion is malignant.