Fast laser welding with scanner on the joint between AZ31 thin sheet and die-casted AZ91D frame for smart phone application

스캐너를 이용한 AZ31 극박판재와 AZ91D 다이캐스팅 프레임의 고속레이저용접

  • 이목영 (포항산업과학연구원 시스템솔루션연구센터) ;
  • 서민홍 (포스코 송도PAC)
  • Received : 2015.03.16
  • Accepted : 2015.03.26
  • Published : 2015.03.31

Abstract

High welding speed and narrow weld seam are favorable for welding of magnesium alloy. Magnesium alloy is recommended for the smart frame because it has several advantages such as low density, high thermal conductivity, EMI shielding capability and good cast ability. This study is for the assembly welding of the magnesium smart frame with high productivity, good performance and low cost. The window for battery on AZ91D frame produced by die-casting was prepared by CNC machining. Corresponding AZ31 blank of 0.2mm thickness was prepared by die-blanking cut. All system set was fixed at the stationary bed but the laser beam was manipulated by scanner up-to 1,000mm/s speed. The weld joint between AZ31 sheet and AZ91D frame was welded by fiber laser on 850~1,000W output power. The joint showed penetration enough but some humping bead. The distortion by the weld heat was almost free because of the quick dissipation of the heat by small beam size and fast welding. Consequently, the thinner magnesium foil was assembled successfully to the magnesium frame of mobile phone.

Keywords

References

  1. 한국철강신문 "마그네슘합금의 기초 및 응용" 2004.11.26
  2. 신광선 "한국마그네슘연구조합 창립 10주년 마그네슘 심포지움", 2014.11.19.
  3. 환경부 '차기(2016-2020년) 자동차 평균 온실가스.연비 기준(안)', 2014.09.05
  4. 이목영, 장웅성, 윤병현, 김숙환, 최상운; 마그네슘 부품제조를 위한 용접기술, 재료마당 20권 5호 (2007년) pp. 35-40.
  5. 이목영; 마그네슘 부품제조를 위한 용접기술, RIST 연구논문, 26권 2호 (2012년) pp. 80-86.
  6. X. Cao, M. Jahazi, J.P. Immarigeon, W. Wallace; A review of laser welding techniques for magnesium alloys, Journal of Materials Processing Technology 171 (2006) pp. 188-204. https://doi.org/10.1016/j.jmatprotec.2005.06.068
  7. S.H. CHOWDHURY, D.L. CHEN, S.D. BHOLE, E. POWIDAJKO, D.C. WECKMAN, and Y. ZHOU; Fiber Laser Welded AZ31 Magnesium Alloy: The Effect of Welding Speed on Microstructure and Mechanical Properties, METALLURGICAL AND MATERIALS TRANSACTIONS A, VOLUME 43A, JUNE (2012) pp. 2133-2147.
  8. Klaus F. Kleine, William J. Fox, Ken G. Watkins; MICRO WELDING WITH PULSED SINGLE MODE FIBER LASERS, ICALEO 2004.
  9. Xiaodong Na "Laser welding" 2010, pp. 47-76.