SEMINAR ON FIBER LASER WELDING

PRESENTED BY VISHAL

Department of Mechanical Engineering PUNJABI UNIVERSITY, PATIALA.

WHAT IS LASER LASER- Light Amplification By Stimulated

Emission Of Radiation, is a mechanism for emitting electromagnetic radiation via the process of stimulated emission

Coherence, monochromaticity and high energy radiation are the main characterstics of laser light.

LASER CLASSIFICATION1. RUBY LASER(CHROMIUM DOPED)2. Nd : YAG and Nd : GLASS LASER3. CO2 LASER 4. X RAY LASER 5. FIBER HOSTED LASER –Erbium and

yttrium ions in double clad form6. Free electron laser

LASER WELDING Laser beam welding is a fusion joining process

that produces coalescence of materials with

the heat obtained from the application of a concentrated coherent light beam impinging upon the surface to be joined

LASER WELDING

LASER WELDINGContinuous wave Co2 laser welding have

limitations in accuracy and high heat input Pulsed Nd : YAG have limitations in maximum

welding speedFuture demand a higher precision control

lower heat input and lower electrical energy consumption.

Continuous fiber laser welding offer these features

FIBER LASER WELDINGIn fiber laser welding ,the laser is generated in

a active fiber medium A silica “active” fiber doped with erbium,

ytterbium is exited by a diode laser sourceFiber brag grating reflect a broad range of

wavelength of light and fiber generate the laser emission

Coil of ytterbium doped multi clad fiber is usedFiber laser available in both type of energy

delivery : pulsed and continuous wave

FIBER LASER WELDING

Fiber laser system

BEAM QUALITY Beam quality of a laser is specified by BEAM

PARAMETER PRODUCT (BPP).It is define as the product of radius of the

beam waist and half the total divergence angle

Low value of BPP imply high beam quality Generally Co2 laser have good beam qulaityFiber laser have achived better beam quality

than solid laser

ADVANTAGE OF FIBER LASER WELDINGNON CONTACT PROCESS SO DISTOTION IS LESSDIMENSION OF THE LASER IS LESSMAINTENCE IS REDUCEDHEAT INPUT IN FLOW IS LESSHEAT EFFECTED ZONE IS LESSWELD GEOMETRY SHAPE IS IMPROVED MINIMUM HEAT REQUIRE FOR FULL DEPTH

PENETRATIONHIGH ASPECT RATION CAN BE ATTAINABLEJOIN THE SMALL AREA CAN WE WELD

DISADVANTAGE OF FIBER LASER WELDINGJOINT MUST BE ACCURATELY POSITIONED

UNDER THE BEAM LASER HAVE THE LOW ENERGY

CONVERSION EFFICIENCY FIBER LASER WELDING SETUP IS NOT

EASLIY AVAILABLEMAXIMUM THICKNESS OF THE WELD IS

19mm

APPLICATIONSDISIMAR MEATAL CAN WE WELD FOR THE

NUCLEAR REACTOR FOR HIGH EFFICECY IN FUTURE

WELD WITH A HIGH PRECISION CAN BE MADE

FOR CONNECTING LEADS ON SMALL ELCTRONIC COMPONENT

BUTT WELDING TITANIUM AND ITS ALLOYAEROSPACE ,SENSORS ,RADAR

COMPONENT ETC

LITREATURE REVIEW YEAR AUTHOR AREA OF

STUDY CONCLUSION

2007 Quintino et al. Welding with high power lasers- a preliminary study

Weld bead geometry represent a finger print format, identify the transient heat input , melting efficiency compare with conventional laser , penetration of laser w.r.t laser speed and heat input

2013 Serizawa et al. Weldability of dissimilar joint between F82H and SUS316L under fiber laser welding

Microstructure of the weld before and after post weld heat treatment , microstructure of base metal of F824, heat affected zone in F824,weld metal and base metal of SUS316L,width of weld zone depend upon speed , position of laser beam should be precisely controlled

LITREATURE REVIEW (cont.) 2015 Ren et al. A comparative study

on fiber laser and co2 laser welding of inconel 617

Comparative study on weld bead geometry and microstructure of fusion zone investigate , CLW weld bead geometry Y shape formed and FLW weld bead geometry I shape, melting efficiency of FLW is large than CLW , highest heat input in CLW is 360 j/mm and in FLW is 210.5 j/mm.

2015 Casalino et al. Ytterbium fiber laser welding of Ti6AL4V alloy

Linear energy have a high influence on the weld bead shape high linear energy promote X shape and less promote Y shape , analysis of microstructure property ,formation of martensite in in FZ,UTS increases 80% and elongation reduced 4-5% Optimization of weld speed for the formation of Y shape weld bead geometry and increase the welding process efficiency (WPE)

REFRENCESL. Quintino , A. Costa , R. Miranda , D. Yapp ,

V. Kumar and C.J. Kong “Welding with high power fiber lasers – A preliminary study” materials and design, 28(2007)1231-1237.

H.erizawa , D.Mori, Y. Shirai, H. Ogiwara and H. Mori “Weldability of dissimilar joint between F82H and SUS316L under fiberlaser welding “fusion engineering and design, 88(2013)2466-2470.

W. Ren , F.Lu , R. Yang , X. Liu , Z. Li and S.R. E. Hosseini “A comparative study on fiber laser and CO2 laser welding of Inconel 617” materials and design,76(2015)207-214.

G. Casalino, M. Mortello and S. L. Campanelli “Ytterbium fiber laser welding of Ti6Al4V alloy ” journals of manufacturing process , xxx(2015)xxx-xxx.