DOCSLIB.ORG

Photonics West• Show Daily

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Photonics West• Show Daily THURSDAY, FEBRUARY 7, 2019 PHOTONICS Brit Berry-Pusey walks away with it WEST• Avenda Health wins Startup Challenge SHOW DAILY Photo: George Nikitin DON’T MISS Prism Awards celebrate the best of photonics THESE EVENTS Winners, categories The world’s first cloud AI-based handheld Smart Vision Lights’ NanoDrive TODAY. Raman spectrometer; a system that derives CloudMinds’ XI AI Raman Spectrometer (Light Sources) is an embedded technology accurate 3D measurements from 2D images; (Detectors & Sensors category) is the world’s that allows tens of amps to reach the LEDs INDUSTRY EVENTS a handheld defect gauge that sizes manufac- first cloud AI-based handheld Raman spec- of a light in 500 ns or less, resulting in a KEY LEGAL ISSUES: HAVE YOUR tured parts as easily as taking a picture on trometer with 785nm laser excitation. light that reaches its full LED power/light QUESTIONS ANSWERED, SIGN UP a phone; and the first frequency-modulat- Double Helix Optics’ SPINDLE intensity when strobing. FOR A FREE SESSION ed continuous CW lidar for smart vehicles. (Diagnostics & Therapeutics) provides un- Modular Photonics’ OMPlex (Optics & 8 AM-12 PM, So. Exhibit Level These were just some of the technologies paralleled precision 3D imaging and track- Optomechanics) devices are based on pas- PHOTONICS INDUSTRY AND that are today the proud bearers of 2019 ing, breaking through limitations in visibili- sive silica chips that increase data trans- PUBLIC POLICY UPDATE 9:15-9:45 AM, Rm. 21, No. Exhibit Prism Awards. ty to allow unprecedented study of inter- and mission rates and reach in optical fiber net- Level The eleventh annual Prism Awards took intra-cellular interactions. works. The chip multiplexes a data signal PHOTONICS WEST EXHIBITION place last night at a gala event at San Fran- Leica’s BLK3D (Imaging & Cameras) into one mode in highly multimode fiber. 10 AM-4 PM, North and South Halls cisco’s Marriott Marquis Hotel. looks like a smartphone, but under the hood, Toptica Photonics’ DLC TOPO STARTUP ALLEY Never before has the Prism Awards recog- it is a 3D measurement and documentation (Scientific Lasers) builds on years of com- 11 AM-12:30 PM, Hall E, Demo Area nized such a broad range of innovation from machine designed to deliver accurate 3D pany innovation to deliver wide tunability, For the full schedule, see the technical so many different companies from so many measurements derived from 2D images. narrow linewidth output, and hands-free program and exhibition guide or download the digital control over the 1.45μm to 4.00μm SPIE Conferences app. Some events require registration. Read daily news reports spectral range. from Photonics West online: 4D Technology’s 4D InSpec XL (Test spie.org/PWnews & Measurement) is a handheld, non-contact part defect gauge that measures manufac- tured parts as easily as taking a picture on Soft LED a phone. The device makes instant, quali- implants fying, 3D measurements of surface features p.33 on manufactured parts being evaluated. Blackmore Automotive’s Doppler Lidar System (Transportation) is the world’s first frequency-modulated CW lidar for au- tonomous vehicles. It gathers instantaneous velocity and long-range measurements of every detected point. Winners all. Wilhelm Kaenders, Toptica; Scott Keeney, nLIGHT; Alexandra Yang, CloudMinds. QD Laser’s Retissa Display (Vision countries around the world. nLIGHT’s Corona (Industrial Lasers) Technology) is a retinal projection laser eye- IN THIS ISSUE. The 2019 finalists, from small companies is a fiber laser with rapidly tunable beam wear—an optical see-through, head-mount- 04 Cassini’s success to large, are advancing technologies in the quality. The Corona provides optimum beam ed display device using a miniature laser 13 Hillenkamp winners areas of healthcare, security, transporta- characteristics for an unprecedented variety projector to draw images directly to the tion, manufacturing, scientific discovery, of processes and materials, addressing a key wearer’s retina. 23 Industry report research, and more. limitation of conventional fixed-beam lasers. MATTHEW PEACH 25 Lasers in space Expert design and manufacturing brought to you every day by >> BOOTH 2151 Observe the latest developments in action at the OptoSigma Technology Demonstration Corner THURSDAY, FEBRUARY 7, 2019 | 03 Future shapes emerging CHALLENGES FACING SILICON PHOTONICS TECHNOLOGY from the quantum fog On Tuesday, industry experts gath- ly provides a lot of value in closing A leading expert in quantum technology weight, and power) is a challenge. “To have ered to discuss progress and chal- high-capacity optical links,” she said. markets is more cautious than most fu- good sensitivity, you need a big SWAP. At lenges in silicon photonics design and The industry is grappling with man- turologists, but says there’s still “plenty the cheaper scale, sensitivity is not good, fabrication. The technology, which in- ufacturing efficiency. Luxtera has been to dream about,” especially when he con- about the same as a quartz clocks. There’s tegrates infrared laser sources with able to automate much of their manu- siders telecom, atomic clocks, and R&D no big advantage,” Robin said. conventional electronics on silicon facturing processes, said Drew Guck- possibilities. “Further down the road, Atomic clocks now range from as low chips, accelerates data transmission enberger, who works at the company. there will be yet more apps for finance as $1,000 to the big ones at $1 million. to promise higher Internet speeds. After they started a new manufactur- and banking, online gaming, security, and That will form the first truly “huge market Data centers, for example, use these ing facility in China, they were able defense,” he predicts. for quantum technology … the only one chips. The chips could also serve a to match its production in their other Thierry Robin, a partner at TEMAT- that will be really commercial.” pivotal role in emerging technologies plants in just two weeks because the YS in France, serving companies like For encrypted communications, such as lidar in self-driving cars, for processes were so automated, he said. Coherent, Nikon, cryptographic key example, and as quantum computing In addition, the industry needs to Siemens, Thales, management and components. outfit chip-making machines with a and others in 18 sharing between However, technical challenges new capability to fabricate photon- countries, has re- remote parties is remain, as speakers pointed out at ics designs, which are generally less viewed current and another challenge. the panel. “In particular, no one has orderly than electronics ones. Global potential quantum “How do you figured out how to integrate a laser Foundries is incorporating free-form apps and markets. distribute the source onto the chip in a commercially design capabilities in which optical de- “Other studies key?” he asked. viable way,” said Philippe Absil of Bel- signers can draw arcs and circles that for quantum tech- Teams of human gium-based IMEC. are crucial to photonics, said Steve nology foresee bil- couriers can be His company sells photonics trans- Palmer, who works for the company. lions of dollars in employed to do ceivers that enable data rates of 50 gi- Companies are also experimenting Toptica Photonics’ Jürgen Stuhler stands the near future. We beside the DLC MDL pro, which powers key exchanges, gabytes per second and beyond. It’s with different manufacturing models. are more cautious quantum computing and optical clocks. By using tamper-re- difficult to engineer a laser based on Infinera uses a vertical integration than most. contrast he is holding a 1940s mechanical sistant hardware silicon, so companies have largely used model in which they design and fab- calculator. Photo: Matthew Peach There will not security mod- other materials, such as III-V semi- ricate everything in-house, including be many full commercial apps in the next ules, or HSM boxes, that can cost up to conductors, to make a laser. But this all hardware and software needed for 10 years, Robin told Tuesday’s Industry $80,000 each. Currently, quantum de- introduces a host of other problems, their product. In contrast, Luxtera Events audience. vices are used in time measurement and such as how to bond the different ma- uses a fabless model, in which the Huge funding is moving the sector, in synchronization systems, for example terials together while maintaining company designs chips in-house but North America, Europe, and especial- with GPS networks. cheap manufacturing costs. outsources the actual fabrication. ly China. He pointed to the 65 quantum In five years, there will be advances That’s why some companies are Speakers also pointed out that startups in the field, including PsiQ, which in measurement for integrated circuits, pursuing alternatives to silicon, such while many companies are pursuing recently raised $65 million. for currents in batteries, and for magne- as indium phosphide-based photon- monolithic integration—getting all the Main market areas are sensing, imag- tometers, gravimeters, and R&D testbeds. ics. Gloria Hoefler of Infinera, based in components on one chip—chip design ing, measurement, and communications. Robin’s full study of markets, “Na- California, talked about her company’s is extremely application-specific. Notable startups where sensors make noscale Quantum Optics,” will be available indium phosphide-based photonics, Other speakers included Doug Gill use of atomic vapors include Twinleaf and by late March on the website of the fund- where they have been able to integrate of IBM and Ashok V. Krishnamoorthy QuSpin, Robin said. ing agency, the European Commission. passive and active components onto of Axalume Inc. For atomic clocks, the SWAP (size, FORD BURKHART one chip. “Indium phosphide real- SOPHIA CHEN In uncertain times, ‘keep your fingers crossed,’ say CEOs Four-executive panel counsels industry on how to prepare for China “softening” and tariff woes. No strangers to stress, four top photonics Systèmes in France; and Andreas Nitze, serve, and stay ahead of the curve.
Load more

Recommended publications
  • High-Power Solid-State Lasers from a Laser Glass Perspective
    LLNL-JRNL-464385 High-Power Solid-State Lasers from a Laser Glass Perspective J. H. Campbell, J. S. Hayden, A. J. Marker December 22, 2010 Internationakl Journal of Applied Glass Science Disclaimer This document was prepared as an account of work sponsored by an agency of the United States government. Neither the United States government nor Lawrence Livermore National Security, LLC, nor any of their employees makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or Lawrence Livermore National Security, LLC. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or Lawrence Livermore National Security, LLC, and shall not be used for advertising or product endorsement purposes. High-Power Solid-State Lasers from a Laser Glass Perspective John H. Campbell, Lawrence Livermore National Laboratory, Livermore, CA Joseph S. Hayden and Alex Marker, Schott North America, Inc., Duryea, PA Abstract Advances in laser glass compositions and manufacturing have enabled a new class of high-energy/high- power (HEHP), petawatt (PW) and high-average-power (HAP) laser systems that are being used for fusion energy ignition demonstration, fundamental physics research and materials processing, respectively. The requirements for these three laser systems are different necessitating different glasses or groups of glasses.
    [Show full text]
  • MECA SENS 2017 Programme& Abstracts
    9th International Conference on Mechanical Stress Evaluation by Neutron and Synchrotron Radiation Hosted by the South African Nuclear Energy Corporation (Necsa) SOC Limited in cooperation with the International Atomic Energy Agency (IAEA) & ABSTRACTS PROGRAMME MECA SENS 2017 Programme & Abstracts MECA SENS 2017 Local Organising Committee Contents Committees 2 Foreword 2 Local Organising Committee 3 Programme Advisory Committee 3 International Scientific Committee 4 Sponsors 5 Event Information 6 Location 6 Registration 9 Internet 9 Catering 9 Presentations 10 Poster session 10 Certificate of attendance 10 Community outreach 10 Programme 11 Spring School - Monday 18 Sept 11 Day 1 – Tuesday 19 Sept 12 Day 2 – Wednesday 20 Sept 13 Day 3 – Thursday 21 Sept 14 List of Abstracts 15 Alain Lodini Plenary Lecture 23 Keynote Presentations 24 Invited Presentations 26 Oral Presentations 42 Poster Presentations 91 School lectures 114 List of Attendees 122 Author Index 126 1 | MECA SENS 2017, Skukuza, South Africa Committees Foreword Dear colleagues On behalf of the Organising Committee, it is a great privilege to welcome and receive you at the Nombolo Mdhluli Conference Centre in the Skukuza Rest Camp, capital of the UNESCO Biosphere Kruger National Park for the proceedings of MECA SENS 2017. This conference continues the tradition of providing a vibrant interactive forum for scientists, students and engineers interested in the most recent developments and capabilities of diffraction based techniques, complemented by mechanical and image-based methods towards rendering information on the prevailing stress conditions and material performance. We thank all participants for submitting excellent contributions. This has enabled the assembly of an exciting scientific program for the next three days.
    [Show full text]
  • Characterization of Laser Peening- Induced Effects on a Biomedical Ti6al4v Alloy by Thermoelectric Means
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital.CSIC Characterization of laser peening- induced effects on a biomedical Ti6Al4V alloy by thermoelectric means Hector Carreón Sandra Barriuso Juan Antonio Porro Jose Luis González-Carrasco José Luis Ocaña Downloaded From: http://opticalengineering.spiedigitallibrary.org/ on 09/23/2015 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx Optical Engineering 53(12), 122502 (December 2014) Characterization of laser peening-induced effects on a biomedical Ti6Al4V alloy by thermoelectric means Hector Carreón,a,* Sandra Barriuso,b Juan Antonio Porro,c Jose Luis González-Carrasco,b,d and José Luis Ocañac aInstituto de Investigaciones Metalúrgicas, UMSNH-IIM, Edif. “U” C.U., 58000-888 Morelia, Mexico bCentro Nacional de Investigaciones Metalúrgicas, CENIM-CSIC, Avenida Gregorio del Amo 8, 28040 Madrid, Spain cUniversidad Politécnica de Madrid, Ctr. Láser UPM, 28040 Madrid, Spain dCentro Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, 28029 Madrid, Spain Abstract. Laser peening has recently emerged as a useful technique to overcome detrimental effects associ- ated with other well-known surface modification processes such as shot peening or grit blasting used in the biomedical field. It is worthwhile to notice that besides the primary residual stress effect, thermally induced effects might also cause subtle surface and subsurface microstructural changes that might influence corrosion resistance and fatigue strength of structural components. In this work, plates of Ti-6Al-4V alloy of 7 mm in thick- ness were modified by laser peening without using a sacrificial outer layer. Irradiation by a Q-switched Nd-YAG laser (9.4-ns pulse length) working at the fundamental 1064-nm wavelength at 2.8 J∕pulse and with water as a confining medium was used.
    [Show full text]
  • Laser Peening Without Coating: Process, Effects and Applications
    LASER PEENING WITHOUT COATING: PROCESS, EFFECTS AND APPLICATIONS Y. Sano 1, N. Mukai 1, M. Obata 1 1 Toshiba Corporation, 8 Shinsugita-cho Isogo-ku Yokohama 235-8523, Japan ABSTRACT This paper reviews the current status of research, development and application on laser peening without coating (LPwC). LPwC imparts compressive residual stress on material by irradiating laser pulses under aqueous environment without any surface preparation. LPwC can be operated without restriction on absorption by water, using water-penetrable green lasers. The effect penetrates 1mm or more, much deeper than that of conventional surface treatment such as shot peening. Accelerating stress corrosion cracking (SCC) tests showed that LPwC effectively prevented the initiation of SCC in sensitized austenitic stainless steels, nickel-based alloys and their weld metals. LPwC remarkably improved high-cycle fatigue properties of steels, aluminum alloys, titanium alloys. Retardation of crack propagation due to stress corrosion and fatigue was also confirmed. LPwC has been utilized to prevent SCC in Japanese nuclear power plants (NPPs) since 1999. KEY WORDS Laser peening, Residual stress, Stress corrosion cracking, Fatigue INTRODUCTION Recent advances in laser material processing have yielded a multitude of innovative processes and applications in various fields. Laser peening without coating (LPwC) is a typical example and blazed a trail in preventive maintenance for SCC in operating nuclear power plants (NPPs), taking full advantage of the inertia-less process over mechanical treatment (Sano, 2000a). LPwC was invented about a decade ago as a surface enhancement technology to introduce compressive residual stress on materials, while exploring new applications of copper vapor lasers (Konagai, 1995).
    [Show full text]
  • 2014 Year in Review
    NEWSLINE 2014 YEAR IN REVIEW LAWRENCE LIVERMORE NATIONAL LABORATORY NOTE NEWSLINE: LOOKING BACK AT 2014 CONTENTS Top 10 science and technology stories of 2014 Top 10 science stories . 2 n 2014, Lawrence Livermore National Laboratory (LLNL) built on a 62-year tradition January . 4 of translating basic science into technologies that ensure national security, address February . 7 I pressing real world problems and expand the boundaries of fundamental science. TOP March . 10 April . 13 The top stories of the year are a reflection of the Laboratory’s ability to apply its core May . 16 national security competencies to a broad set of rapidly evolving national and global 10 June . 19 challenges, including: energy, climate change, biodefense and detection, forensic July . 23 science, high performance computing and materials science. August . 26 September . 29 The capabilities developed and applied to this research, such as high performance computing (HPC) and additive October . 32 manufacturing, also serve to enhance the nation’s economic vitality and global competitiveness. November . 36 December . 41 Because evaluating the long-term impact of recent scientific developments on a field of study or science Recognition and Awards . 44 in general is difficult at best, the following advances are not listed in order of scientific importance. These This issue of Newsline was produced by the Public represent only a sampling of the science and technology produced at Lawrence Livermore during the 2014 Affairs Office. It represents a sample of the science and technology, people and operations highlights of calendar year. the year. It is available on the LLNL website. On the cover: Top stories of the year.
    [Show full text]
  • Effective Simulation and Optimization of a Laser Peening Process BE ACCEPTED in PARTIAL FULFILLMENT of the REQUIREMENTS for the DEGREE of Doctor of Philosophy
    Effective Simulation and Optimization of a Laser Peening Process A dissertation submitted in partial fulfillment of the requirements for the degree of the Doctor of Philosophy By GULSHAN SINGH B.S., Jai Narain Vyas University, Jodhpur, India, 2001 M.Tech., Indian Institute of Technology, Kanpur, India, 2003 2009 Wright State University Wright State University SCHOOL OF GRADUATE STUDIES August 10, 2009 I HEREBY RECOMMEND THAT THE DISSERTATION PREPARED UN- DER MY SUPERVISION BY GULSHAN SINGH ENTITLED Effective Simulation and Optimization of a Laser Peening Process BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy . Ramana V. Grandhi, Ph.D. Dissertation Director Ramana V. Grandhi, Ph.D. Director, Engineering Ph.D. Program Joseph F. Thomas, Jr., Ph.D. Dean, School of Graduate Studies Committee on Final Examination Ramana V. Grandhi, Ph.D. Nathan Klingbeil, Ph.D. Ravi Penmetsa, Ph.D. Allan H. Clauer, Ph.D. Robert Brockman, Ph.D. ii Abstract Singh, Gulshan, Ph.D. in Engineering Program, Wright State University, 2009. Effective Simulation and Optimization of a Laser Peening Process. Laser peening (LP) is a surface enhancement technique that has been applied to improve fatigue and corrosion properties of metals. The ability to use a high energy laser pulse to generate shock waves, inducing a compressive residual stress field in metallic materials, has applications in multiple fields such as turbomachinery, airframe structures, and medical appliances. In the past, researchers have investigated the effects of LP parameters experimentally and performed a limited number of simulations on simple geometries. However, monitoring the dynamic, intricate relationships of peened materials experimentally is time consuming, expensive, and challenging.
    [Show full text]
  • Thursday, May 10, 2007
    ROOM 318-320 ROOM 321-323 ROOM 324-326 ROOM 314 ROOM 315 ROOM 316 ROOM 317 ROOM 336 CLEO JOINT C LEO QELS 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. 8:00 a.m. – 9:45 a.m. CThA • Fundamentals of CThB • Novel JThA • Attosecond CThC • χ2/Cascaded χ2 CThD • Optical Polymers CThE • Spectral Control of QThA • Novel Dynamic QThB • Plasmonics I Femtosecond Laser/ Semiconductor Laser Dynamics Devices Warren N. Herman; Lab Solid-State Lasers Measurements in Metals Mikhail Noginov; Norfolk Material Interactions Cavities Presider to Be Announced Robert Fisher; R. A. Fisher for Physical Sciences, Hajime Nishioka; Inst. for Michael Woerner; Max- State Univ., USA, Presider Donald Harter; IMRA Richard Jones; Intel Corp., Associates, USA, Presider Univ. of Maryland, USA, Laser Science, Japan, Born-Inst., Germany, America Inc, USA, USA, Presider Presider Presider Presider Presider Tutorial Invited Invited Tutorial Invited CThA1 • 8:00 a.m. CThB1 • 8:00 a.m. JThA1 • 8:00 a.m. CThC1 • 8:00 a.m. CThD1 • 8:00 a.m. CThE1 • 8:00 a.m. QThA1 • 8:00 a.m. QThB1 • 8:00 a.m. Ultrafast Micro and Nanomachining, Nanoscale Semiconductor Plasmon La- Probing Proton Dynamics in Molecules Parametric Generation in AlGaAs/AlOx Biomimetic Optical Polymers, James Widely Tunable Yb:KYW Laser Locked Ultrafast Spectroscopy on Photonic Nano-Particle Ions and Atoms, Nabil Gerard Mourou; Ecole Polytechnique de sers, Farhan Rana1, Christina Manolatou1, on an Attosecond Time Scale, Sarah Waveguides: Performances and Perspec- Shirk1, Guy Beadie1, Richard S.
    [Show full text]
  • Laser Peening Fact Sheet
    Hepburn and Sons LLC “Trusted advisors to the American Maritime Industry” TECHNOLOGY FACT SHEET – Laser Shock Peening TECHNICAL CHALLENGE 10X Compressive residual stress • Aluminum shipbuilding on the rise in the Navy, leading to benefits over other peening materials problems like stress corrosion cracking (SCC) and methods and treatments sensitization • Repair yards tasked with these substantial repairs • Aluminum repair has significant rework, as it is difficult to work with • Welding repairs impart large stresses on and deform the 48X aluminum SCC on aluminum ship Lifetime extension of • Flame straightening not permitted on marine grade aluminum superstructure sensitized aluminum when laser shock peened versus • Common aluminum forming methods are laborious, costly, and no treatment time-consuming TECHNOLOGY OVERVIEW • High-energy pulsed laser directed at material surface to generate pressure pulses • Shock wave plastically yields and cold works the 1-5 mm material to generate deep compressive stresses Range of compressive residual stress depth as a • Residual stress layers are orders of magnitude result of laser shock peening deeper than that achievable with shot peening • Highly predictive and deterministic stress Laser peening a metal surface profiles • Used successfully in the aerospace industry for nearly 20 years • Significantly improves aluminum lifespan • 20 years Arrests crack growth and mitigates stress Length of time that laser corrosion cracking shock peening has been successfully used in the • Mitigates aluminum sensitization
    [Show full text]
  • Laser Peening for Prevention of Fatigue Failures
    LASER PEENING FOR PREVENTION OF FATIGUE FAILURES David F. Lahrman Peter A. Gaydos LSP Technologies, Inc. United States ABSTRACT Laser peening is an innovative commercially-available surface enhancement process for increasing the fatigue life of metal components. The process produces deep residual compressive stress into treated surfaces, typically five to ten times deeper than conventional metal shot peening. These deep compressive residual stresses inhibit the initiation and propagation of fatigue cracks. Laser peening has been particularly effective in increasing the resistance to fatigue crack propagation initiated from foreign object damage in titanium alloy fan and compressor blades of aircraft gas turbine engines. [1,2,3,4] However, the potential application of this process is much broader, encompassing automotive parts, orthopedic implants, tooling and dies, and others. Significant progress has been made to lower the cost and increase the throughput of the process, making it affordable for numerous applications. This paper reviews the status of laser peening technology, material property enhancements, and potential applications. KEYWORDS Laser shock peening, fatigue, life, residual stress, surface, enhancement HOW LASER PEENING WORKS Laser peening drives a high amplitude shock wave into a material surface using a high energy pulsed laser. The effect on the material being processed is achieved through the mechanical “cold working” effect produced by the shock wave, not a thermal effect from heating of the surface by the laser beam. The laser system is a high-energy, pulsed neodymium-glass laser system having a wavelength of 1.054 µm. The laser peening system produces very short laser pulses, selectable from 8 to 40 nanoseconds, with a pulse energy of up to 50 joules.
    [Show full text]
  • Effects of Laser and Shot Peening on Fatigue Life in Friction Stir Welds
    Effects of Different R ratios on Fatigue Crack Growth in Laser peened Friction Stir Welds Omar Hatamleh1,a, Lloyd Hackel2,b , Scott Forth3,c 1) Structures & Dynamics Branch, NASA-Johnson Space Center, Houston, Texas 77058 2) Metal Improvement Company, 7655 Longard Rd, Livermore, California 94551 3) Materials & Processes Branch, NASA-Johnson Space Center, Houston, Texas 77058 [email protected], [email protected], [email protected] Keywords: friction stir welding, laser peening, shot peening, fatigue crack growth Abstract. The influence of laser peening on the fatigue crack growth behavior of friction stir welded (FSW) Aluminum Alloy (AA) 7075-T7351 sheets was investigated. The surface modification resulting from the peening process on the fatigue crack growth of FSW was assessed for two different R ratios. The investigation indicated a significant decrease in fatigue crack growth rates resulting from using laser shock peening compared with unpeened, welded and unwelded specimens. The slower fatigue crack growth rate was attributed to the compressive residual stresses induced by the peening. 1. Introduction Friction stir welding (FSW) was invented by the Welding Institute in England in 1991 [1]. Since then, FSW has emerged as a promising solid state process with encouraging results, particularly when used on high strength aerospace aluminum alloys that are generally difficult to weld [2]. FSW transforms metals into a plastic state at a temperature below the melting temperature of the material, and then mechanically stirs the materials together, under pressure to produce high strength bonds. Residual stresses developed during welding [3,4] can have a significant effect on the service performance of welded material with respect to fatigue properties, and fatigue crack growth process.
    [Show full text]
  • Laser Peening Process and Its Impact on Materials Properties in Comparison with Shot Peening and Ultrasonic Impact Peening
    Materials 2014, 7, 7925-7974; doi:10.3390/ma7127925 OPEN ACCESS materials ISSN 1996-1944 www.mdpi.com/journal/materials Review Laser Peening Process and Its Impact on Materials Properties in Comparison with Shot Peening and Ultrasonic Impact Peening Abdullahi K. Gujba 1 and Mamoun Medraj 1,2,* 1 Department of Mechanical and Industrial Engineering, Concordia University, 1455 De Maisonneuve Blvd. W., Montreal, QC H3G 1M8, Canada; E-Mail: [email protected] 2 Department of Mechanical and Materials Engineering, Masdar Institute, Masdar City, P.O. Box 54224, Abu Dhabi, UAE * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +1-514-848-2424 (ext. 3146); Fax: +1-514-848-3175. External Editor: Douglas Ivey Received: 17 October 2014; in revised form: 18 November 2014 / Accepted: 27 November 2014 / Published: 10 December 2014 Abstract: The laser shock peening (LSP) process using a Q-switched pulsed laser beam for surface modification has been reviewed. The development of the LSP technique and its numerous advantages over the conventional shot peening (SP) such as better surface finish, higher depths of residual stress and uniform distribution of intensity were discussed. Similar comparison with ultrasonic impact peening (UIP)/ultrasonic shot peening (USP) was incorporated, when possible. The generation of shock waves, processing parameters, and characterization of LSP treated specimens were described. Special attention was given to the influence of LSP process parameters on residual stress profiles, material properties and structures. Based on the studies so far, more fundamental understanding is still needed when selecting optimized LSP processing parameters and substrate conditions.
    [Show full text]
  • Laser Peening Vs. Shot Peening: Engineering of Residual Stresses, Surface Roughness and Cold Working
    Laser Peening vs. Shot Peening: engineering of residual stresses, surface roughness and cold working 0. Higounenc1 1 Metal Improvement Company I Curtiss Wright Surface Technologies, Bayonne, France Abstract In Laser Peening (LP), compared to Shot Peening (SP), the magnitude of residual compressive stress at the surface is the same: about 60% of elastic limit; but the depth is much higher. In Low Cycle Fatigue (LCF) depth of residual compressive stress is beneficial because it does not only delay crack initiation, but also crack propagation. Depth of residual stress is also crit­ ical in Foreign Object Damage (FOO) and Crack Grow Rate (CGR) applications. Changes in surface roughness, as soon as cold work, are much more significant in shot SP compared to LP. Those changes can have a positive, or a negative influence depending on application and condition: HCF or LCF, deteriorating or non-deteriorating environment such as corrosion or FOO, fretting, surface contact fatigue. Thus, LP is complementary to SP in some specific applications such as LCF, FOO, CGR. The other advantage is the extremely high process control that allow more easily to take into ac­ count the credit of LP in the design .. Keywords: shot peening, laser peening, fatigue life, crack nucleation, crack propagation Introduction Laser Peening (LP) is a process in which an iintense beam of laser light (irradiance 2 to 1OGW/cm2) is directed on to a sacrificial ablating material placed on the surface of the com­ ponent to be treated. The light rapidly vaporizes a thin portion of the ablative layer, producing a plasma that is confined by the inertia of a thin laminar layer of water (-1 mm thick) flowing over the surface.
    [Show full text]