• Title, Summary, Keyword: 파이버 레이저

Search Result 53, Processing Time 0.071 seconds

Characteristics of Fiber Laser Welding on STS304L for GTT MARK III Membrane (GTT MARK III 스테인리스강 STS304L의 파이버 레이저 용접특성)

  • Kim, Jong-Do;Lee, Chang-Je;Song, Moo-Keun
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.36 no.8
    • /
    • pp.1069-1075
    • /
    • 2012
  • Laser is high density heat source, so it can make high speed welding with minimum heat input possible. Especially the high power fiber laser is recently commercialized and has high beam quality and the smallest system size compared with conventional laser due to it's unique oscillating mechanism. Because of these advantages it's thought that the most suitable heat source for LNG cargo tank welding precess which has to be conducted inside of ships. In this study fiber laser was used for welding of stainless steel for LNG carrier to applicate laser welding technique for shipbuilding industry. 1.2mmt STS304L of austenite stainless steel which apply to cargo tank was used for fiber laser welding. Butt and lap welding was conducted changing laser power, welding speed, then penetration characteristic was analyzed and optimal parameters for each materials. Consequently, we found that same or better mechanical properties were obtained in weld compared to base metal.

Weldability with Process Parameters During Fiber Laser Welding of a Titanium Plate (II) - The Effect of Control of Heat Input on Weldability - (티타늄 판재의 파이버 레이저 용접시 공정변수에 따른 용접특성 (II) - 입열량 제어에 따른 영향 -)

  • Kim, Jong Do;Kim, Ji Sung
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.40 no.12
    • /
    • pp.1055-1060
    • /
    • 2016
  • Laser welding is a high-density energy welding method. Hence, deep penetration and high welding speed can be realized with lower heat input as compared with conventional welding. The heat input of a CW laser welding is determined by laser power and welding speed. In this study, bead and lap welding of $0.5mm^t$ pure titanium was performed using a fiber laser. Its weldability with laser power and welding speed was evaluated. Penetration, bead width, joining length, and bead shape were investigated, and the mechanical properties were examined through tensile-shear strength tests. Welds with sound joining length were obtained when the laser power and welding speed were respectively 0.5 kW and 2.5 m/min, and 1.5 kW and 6 m/min, and the weld obtained at low output presented better ductility than that obtained at high output.

Compensation for laser chirping and chromatic dispersion using optical equalizer in fiber optic transmission systems (광 파이버 전송 시스템에서 광 등화기에 의한 레이저 처핑 및 색분산 보상)

  • Chang, Jin-Hyeon;Jung, Jin-Ho;Han, Wook;Kim, Yung-Kwon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.9 no.1
    • /
    • pp.16-24
    • /
    • 1998
  • In a high speed long haul fiber optic communication system using modulation, fiber chromatic dispersion and laser chirping can cause serious performance degradations. In this paper, the combined effect of laser chirping and chromatic dispersion on the per- formance of 2.5[Gbps] rate lightwave systems operating at a wavelength of 1550[nm] was investigated. Also we used an optical equalizer to compensate the laser chirping and fiber dispersion, and knew that the receiver sensitivity was improved by about 2 ~ 4[dB].

  • PDF

Welding characteristics of Metal bellows using a Fiber laser (파이버 레이저를 이용한 밸로우즈 용접특성에 관한연구)

  • Kim, Jeng-O;Lee, Jae-Hoon;Lee, Seung-Woo
    • Journal of Korean Society of Laser Processing
    • /
    • v.16 no.3
    • /
    • pp.22-26
    • /
    • 2013
  • Fiber laser welding was performed on SUS Materials metal bellows. The results can be summarized as follows: When we tried to change welding focus location. we get the best welding line when focus location placed 0mm. In product welding, We could make a satisfactory product in constant area by applying optimized conditions and show a table that is able to help producer easily to apply it to manufacturing. In comparison with existing TIG and plasma welding, welded bellows by fiber laser has faster processing speed, smaller thermal effect, very narrow welding area and fine surface.

  • PDF

Weldability of STS316L for LNG Carrier by Fiber Laser (파이버 레이저를 이용한 LNG선용 STS316L의 용접특성)

  • Kim, Jong-Do;Lee, Jae-Beom;Lee, Chang-Je;Song, Moo-Keun;Nam, Gi-Jeong
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.36 no.8
    • /
    • pp.1061-1068
    • /
    • 2012
  • These days, world wide interest about global warming and environmental pollution and exhausting fossil fuel which have been main energy source in all around the world. So many country have tried to find out the solution by investing new & renewable and clean energy. Therefore LNG have been widely used as a substitution of fossil fuel and clean energy that emits less pollutant like SOx, NOx. Therefore LNG consumption has been quickly raised and LNG carriers have been getting larger for decades. In this study, high power fiber laser was used for welding of stainless steel for LNG carrier to increase its productivity. Used material was STS316L which has low carbon less than 0.03% and its thickness was 8 mm. We carried out bead, lap and butt welding by using the fiber laser which has maximum power up to 5kW. As a result, we could find out that lap and butt joint was possible at welding speed of 2.0m/min and 3.0m/min respectively.

Study on Fiber Laser Welding Characteristics of Copper for Secondary Battery Material (이차전지 소재용 구리의 파이버 레이저 용접 특성에 관한 연구)

  • Park, Eun Kyeong;Lee, Ka Ram;Lee, Hyun Jung;Yoo, Young Tae
    • Journal of Korean Society of Laser Processing
    • /
    • v.17 no.3
    • /
    • pp.1-9
    • /
    • 2014
  • In this study, we analyzed fiber laser welding for the pure copper thin plates in a series of secondary lithium-ion batteries; and performed the experiment for the purpose of the preceding study to replace bolt joints method the with the laser welding method. We have changed the peak power of the laser from 5 to 6kW, the pulse duration by 4, 6, 8, and 10ms, the frequency by 10, 12, 16, and 25Hz, and the focal position by -3, 0, and +3. As a result, when the focal position is at +3, the peak power is 5kW, and the pulse duration and the Frequency are 4ms and 25Hz, respectively, we obtain 2.1 and 2.5 times better tensional strengths, respectively, than the highest values of tensional strengths obtained with the focal positions at 0 and -3.

  • PDF

A Study on SS400 Cutting Characteristics using Continuous Wave Fiber Laser (연속파 파이버 레이저를 이용한 SS400의 절단 특성에 관한 연구)

  • Oh, Yong-Seok;Lee, Ka-Ram;Park, Eun-Kyeong;Yoo, Young-Tae
    • Journal of The Korean Society of Manufacturing Technology Engineers
    • /
    • v.21 no.4
    • /
    • pp.644-650
    • /
    • 2012
  • This paper show the 2kW fiber laser cutting properties of SS400. The study was comparison of traditional 4kW $CO_2$ Laser cutting and 2kW Fiber laser cutting characteristics for the application of Industrial 2D Laser Cutting Machine. The laser used in this investigation was an IPG YLU-2000 multi-mode Ytterbium Fiber machine with a maximum power of 2000W and a wave length of 1070 nm. The laser was used in its Continuous Wave (CW) mode with an approximately top hat beam intensity distribution. Fiber laser high quality cuts at a large range of speeds (ranging from 2000 to 3800 mm/min) which has been obtained for the 2.3mm Sheet of SS400. 2kW power Fiber laser cut was able to max. 20mm sheets of SS400 (speed range from 650 to 850 mm/min). Fiber laser cutting used in conventional hole nozzle could cut 12mm SS400 but used in special dual cutting nozzle could cut 20mm SS400.

A Study on the Fiber Laser welding of Ultra-Low Carbon Interstitial Free Steel for Automotive (자동차용 무침입형 극저탄소강의 파이버 레이저 용접에 대한 연구)

  • Oh, Yong-Seok;Shin, Ho-Jun;Yang, Yun-Seok;Hwang, Chan-Youn;Yoo, Young-Tae
    • Journal of The Korean Society of Manufacturing Technology Engineers
    • /
    • v.20 no.3
    • /
    • pp.342-349
    • /
    • 2011
  • The purpose of this paper is to describe experimental results about the butt welding and bead on plate welding of the high power Continuous Wave (CW) Fiber laser for Ultra-low carbon Interstitial Free(IF) steel plate for gear part of car. After being welded of the gear parts by the fiber laser and electron beam Microstructures of melting zone had been mixed acicular, granular bainitic, quasi-polygonal and widmanstatten ferrite because of a radical thermal diffusion after welding, difference of critical volume and grain size. As a result of experiment, when gear parts were welded by the fiber laser and electron beam, the fiber laser welding has been stable properties without internal defects more than the electron beam welding. Therefore it has the very advantages of welding high quality and productivity more than conventional melting method. The optimal welding processing parameters for gear parts were as follows : the laser power and welding speed were 3kWatt, 30mm/sec respectively. At this time heat input was $21.2{\times}10^3J/cm^2$.