Guru Nanak's Mool Mantra and the Word 'Ek Onkar' or 'Ek Oh Beant'
Mool C. Gupta - University of Virginia School of ... · PDF fileCharles L. Brown Department of...
Transcript of Mool C. Gupta - University of Virginia School of ... · PDF fileCharles L. Brown Department of...
Charles L. Brown Department of Electrical and Computer Engineering
Laser Based Manufacturing
Mool C. GuptaLangley Distinguished Professor & NSF I/UCRC Center Director
Department of Electrical & Computer Engineering
University of Virginia
Presentation to industrial members 3-3-10
Charles L. Brown Department of Electrical and Computer Engineering
National Science Foundation Center
For Laser Based Manufacturing
Center Mission --
Develop Science, Engineeringand Technology Base for
Laser and Plasma Processing of Materials, Devices and
Systems for Advanced Manufacturing
Charles L. Brown Department of Electrical and Computer Engineering
Partnership
Projects
Industry
Fed. LabsUniv.
State NSF
MembershipMembership
Membership
CIT
Overhead &
Facility
Funds& NationalRecognition
National Science Foundation Industry University Cooperative Research Center for Laser Based Manufacturing
University of Virginia University of Michigan-Ann Arbor
University of Illinois
Southern Methodist University
Charles L. Brown Department of Electrical and Computer Engineering
Industrial Advisory Board MembersNASA Langley Research Center
AREVA GroupNAVAIR
GE Global ResearchGE Aviation
General Motors R&DToyota USA
Lockheed Martin Halliburton
IMRANuvonyx
Trinity IndustriesArmy Research Office
Spectra PhysicsTRUMPF
Lee Laser, Inc., FL; Fruth Innovative Technologies, GmbH, Germany ;
Charles L. Brown Department of Electrical and Computer Engineering
•Laser Material Interactions
•Process sensing, monitor and control
•Materials and metallurgical aspects
•Laser systems
•Optics and beam delivery systems
•Laser micromachining, welding, plasma processing and hybrid processes
•Micromachining. Welding, texturing, drilling, surface modification, cladding, shaping, alloying, cleaning, sintering
Various Aspects of Laser Based Manufacturing
Charles L. Brown Department of Electrical and Computer Engineering
•Laser cleaning of surfaces-(Navair- Boeing and Bell Helicopter)
•Laser notch formation- (Navair, NASA)
•Laser micromachining- (Siemens & formerly DuPont subsidiary)
•Laser induced compressive stresses-(AREVA Group)
•Laser sintering of oxidation resistant UHT materials-(AFOSR)
•Fiber based detection of high tempr. through luminescence (NASA)
•Real time monitoring of weld pool through laser imaging (AREVA)•Butterfly Color Formation-(Alcoa Corporation)
•Other : solar energy( laser fired contacts, laser doping, laser morphology control), nanocomposites (electrical conducting plastics through carbon nanotubes), optical sensors
LASER BASED RESEARCH PROJECTS•Laser surface texturing-(NSF, NASA)
Charles L. Brown Department of Electrical and Computer Engineering
Research Infrastructure• Laser and Optics Lab
– Two fiber lasers (IPG), 50 ns pulse width– High power CW diode laser (250W)– Fs laser– Two Nd-YAG laser (10 ns pulse width– Optical measurement equipment– Computer controlled stages and galvo systems
• Clean Room Facility for Microfabrication– Optical Lithography, e-Beam Lithography,
sputtering, e-beam deposition, ion etching• Characterization Facility- SEM, TEM, AFM, X-
ray…..• Sensor and Photovoltaic Device Fabrication
and Characterization Labs
Charles L. Brown Department of Electrical and Computer EngineeringDiode pump Solid state laser
Diode laser
IPG fiber laser
YAG laserYAG laser
Charles L. Brown Department of Electrical and Computer Engineering
Laser Texture-Experimental Setup
Wavelength: 800 nm
Pulse Repetition Rate: 1 KHz
Pulse Energy: 1 mJ
Charles L. Brown Department of Electrical and Computer Engineering
Applications
• Generation of large surface area • Light trapping properties
– High contrast marking, logos, serial #’s etc– Super hydrophobic– Thermal management– Surface texture, ice formation, flow– Bond strength improvement– Photovoltaics, bio-implants etc.
Publications: 1. "Pulse width effect in ultrafast laser processing of materials", Applied Physics A : Matls. Sci. & Processing, Applied Physics A, Vol. 81, 1257, (2005).2. “Semiconductor laser crystallization of a-Si:H on conducting tin oxide coated glass for solar cell and display applications”, Appl. Phys. A: Materials Science and Processing A80, 1077, (2005).3. B. K. Nayak, M.C. Gupta and K. W. Kolasinski, “Formation of nanotexture conical microstructures in titanium metal surface by femtosecond laser irradiation”, Applied Physics, A, vol 90, p. 399 (2008).
Charles L. Brown Department of Electrical and Computer Engineering
Laser Marking & Superhydrophobic Surfaces
Charles L. Brown Department of Electrical and Computer Engineering
Inconel 690 laser cladding on Inconel 600 for nuclear applicationsLaser Aided Manufacturing for Nuclear Energy
SEM cross-section
• Improve corrosion resistance of coolant pipes by laser claddinglower cost / higher processing speedgood adhesion & high densityminimal residual stress in base materialgood chemical/mechanical/thermal stability
avoid premature failure & enhance lifereduce repair costsmaintain generator safety, efficiency, and up-timetransfer technology of laser metal cladding
Charles L. Brown Department of Electrical and Computer Engineering
Laser Aided Manufacturing for Nuclear Energy
Charles L. Brown Department of Electrical and Computer Engineering
Laser Processing of Ultra High Temperature Ceramics
xy
Nd:YAG LaserMirror
Lens
Argon gas environment
Nd:YAG Laser
High power CW laser
Stage
Advantages:-Non-contact process, eliminating contamination from walls-Achieving extremely high temperature (>4000°C), and the control of rapid heating and cooling rates-Sintering to high density, with minimal post processing requirements
Objectives:-Provide basic understanding of laser sintering mechanism for ultra high temperature ceramics (UHTCs)-Fabrication of cladding layer and 3-D structures using UHTCs for Air Force applications.
Charles L. Brown Department of Electrical and Computer Engineering
Hybrid Processing of Ultra High Temperature Ceramics
Advantages:- Laser preheats sample to facilitate MW absorption.- Volumetric heating increases throughput.- High power allows faster processing.
Objectives:- Investigate feasibility for [laser + microwave] sintering of ultra high temperature ceramics (UHTCs)- Explore resonant interaction between multiple energy sources.- Improve sintered properties by decreasing grain growth.
CW Laser
MW
Charles L. Brown Department of Electrical and Computer Engineering
Laser + MW Processing of Ultra High Temperature Ceramics
Charles L. Brown Department of Electrical and Computer Engineering
Laser cleaning of Ti alloy Tubing’s used in aircrafts
Charles L. Brown Department of Electrical and Computer Engineering
Laser Cleaning and welding
1/2”
3/8”
1/4”
Objective: Evaluate feasibility of laser cleaning of Titanium for welding applications (no chemicals)
Charles L. Brown Department of Electrical and Computer Engineering
Laser Micro-machining EDM
Sharp notch tip● Smaller heat effected zone
Laser micro notch fabrication
NAVAIR
Charles L. Brown Department of Electrical and Computer Engineering
0.10 inch
0.125 inch
Objective: Produce sharp notches in aluminum metal surfaces for mechanical testing
NASA
Charles L. Brown Department of Electrical and Computer Engineering
750 mil / 30 mil
Objective: Demonstrate laser micromachining of slots in carbon nanofiber based polymer composites
NASA
Charles L. Brown Department of Electrical and Computer Engineering
Laser Drilled Hole in S.S. 153 µm thick
Fs Laser Micromachining
Laser Micromachining
Siemens
DuPont
Charles L. Brown Department of Electrical and Computer Engineering
LASER-DRIVEN COMPRESSIVE WAVE GENERATION
• Turbine Blade & Vessel in Power Plants• Medical applications
Laser Shot Peening
Charles L. Brown Department of Electrical and Computer Engineering
Example apparatus setup for weld pool optical imaging (ref 2)
Real time monitoring of weld pool surface
AREVA Group
Charles L. Brown Department of Electrical and Computer Engineering
Laser Imaging of Weld Pool Surface
Charles L. Brown Department of Electrical and Computer Engineering
Excitation laser beam
Fluorescent light beam
High temperature fluorescent film on optical fiber surface
Spectrometer
Laser
Monitoring of fluorescent light intensity and life time
Fiber Based High Temperature Sensor using Fluorescent Method
NASA
Charles L. Brown Department of Electrical and Computer Engineering
1 μm
Laser texturing
Laser notch formation
Laser sintering
Laser surface cleaning
Laser micromachining
Charles L. Brown Department of Electrical and Computer Engineering
CONCLUSIONS
•Lasers provide a competitive edge in manufacturing
•Significant growth is expected in Laser Based Manufacturing
•Benefits by UVa Collaboration:
•a long experience in laser based manufacturing and interaction with industry
•Excellent infrastructure in lasers, optics and materials/process analysis
•Educational/training in area of laser technology and its applications in manufacturing