Browse > Article
http://dx.doi.org/10.5781/KWJS.2010.28.1.066

A Study of Weldability for Pure Titanium by Nd:YAG Laser(IV) - Lap Welding and Application for Heat Exchanger -  

Kim, Jong-Do (Division of Marine System Engineering, Korea Maritime University)
Kwak, Myung-Sub (Industrial Application R&D Institute, DSME. Co.)
Lee, Chang-Je (Graduate School, Korea Maritime University)
Kil, Byung-Lea (Division of Marine System Engineering, Korea Maritime University)
Publication Information
Journal of Welding and Joining / v.28, no.1, 2010 , pp. 66-71 More about this Journal
Abstract
With large specific strength and outstanding corrosion resistance and erosion resistance in sea water, titanium and titanium alloy are widely used in heat exchanger production. In particular, pure titanium demonstrates outstanding molding performance and may be considered optimal for production of heat exchanger. Since titanium is very vulnerable to oxidation and embrittlement during welding, processes with less heat input are widely used, and laser welding is widely applied by considering production performance and shield etc in atmosphere. So far, 1st report and 2nd report compared and analyzed embrittlement degrees by bead colors of weldment through oxygen and nitrogen quantitative analysis and hardness measurement, and evaluated welding performance and mechanical properties of butt welding. This study evaluated field applicability of lap welding to heat exchange plate of LPG re-liquefaction device for ships through tensile stress test, hardness test and internal pressure test etc after deducing optimal weding condition and applying to actual heat exchange plate. In bead overlap area, the experiment produced sound welds with no porosity or defect by increasing and decreasing laser power, and tensile-shear test results indicated virtually the same tension and yield strength as base metal. As a result of measuring hardness at lateral cross section and bead overlap zone of actual heat exchanger welds, hardness difference within 20Hv was produced at base metal, HAZ and weldment, and as a result of pneumatic and hydraulic pressure test, no leakage occurred.
Keywords
Pure titanium; Nd:YAG laser; Tensile-shear strength test; porosity; Slope up & down;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
1 Hitoshi Wake, Hiromichi Takahashi, Toshihiro Takimoto, Hirokazu Takayanagi, Kinichi Ozawa, Hideo Kadoi, Mina Okochi, Tadashi Matsunaga : Development of an Electrochemical Antifouling System for Seawater Cooling Pipelines of Power Plants Using Titanium, Biotechnology and Bioengineering, 95(2006), No.3   DOI   ScienceOn
2 Chen, F.K. ; Chiu, K.H., Stamping formability of pure titanium sheets, Journal of materials processing technology, 170-1/2,(2005), 181-186   DOI   ScienceOn
3 Harada Yasunori, Furukawa Yosuke, Murao Takuji, Mori Ken0ichiro, Tsuchida Noriyuki, Fukaura Kenzo : Formability and Improvement of Surface Roughness in Multistage Deep Drawing Processes of Beta Titanium Alloy Sheet, Journal of Japan Society for Technology of Plasticity, 47-528(2006), 850-854 (in Japanese)   DOI
4 Jong Do Kim, Myung Sub Kwak, Moo Keun Song : A Study of Weldability for Pure Titanium by Nd:YAG Laser(III) - Welding Properties of Edge Welding -, Journal of KWJS, 27-6 (2009), 74-79 (in Korean)   과학기술학회마을   DOI
5 Jong Do Kim, Myung Sub Kwak, Moo Keun Song, Seung-Ha Park : A Study of Weldability for Pure Titanium by Nd:YAG Laser(II) - Welding Properties of Butt Welding -, Journal of KWJS, 27-6 (2009), 68-73 (in Korean)   과학기술학회마을   DOI
6 Toshikatsu Asahina and Yosuke Itoh : Structures and Mechanical Properties of Butt Welded Pure Titanium Sheet Using Pulsed YAG Laser, Journal of Japan Institute of Light Metals, 55-8 (2005), 337-342 (in Japanese)   DOI
7 Jong Do Kim, Myung Sub Kwak, Chang Soo Kim : A Study of Weldability for Pure Titanium by Nd:YAG Laser(I) - Weld Properties with Shield Conditions -, Journal of KWJS, 27-5(2009), 55-61 (in Korean)   과학기술학회마을   DOI