DOI QR코드

DOI QR Code

Al6061-T6 열처리 잔류응력의 유한요소해석 및 측정

FE-Simulation and Measurement of the Residual Stress in Al6061 During T6 Heat Treatment

  • Ko, Dae-Hoon (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Tae-Jung (Technical Research Laboratory, Mico C&C Co.) ;
  • Lim, Hak-Jin (Defense Product Technical Research Laboratory, Poongsan Co.) ;
  • Lee, Jung-Min (Defense Product Technical Research Laboratory, Poongsan Co.) ;
  • Kim, Byung-Min (School of Mechanical Engineering, Pusan Nat'l Univ.)
  • 투고 : 2010.10.12
  • 심사 : 2011.04.28
  • 발행 : 2011.07.01

초록

본 연구의 목적은 Al6061 의 T6 열처리 시 발생되는 잔류응력의 변화를 예측하는 것이다. Al6061-T6 의 일반적인 열처리 조건인 용체화처리($530^{\circ}C$, 2hr)와 인공시효($175^{\circ}C$, 9hr)에서 인공시효 시간에 따라 잔류응력 변화를 고려하였다. 잔류응력 예측은 열처리 실험을 수행하여 대류 열전달계수를 확보하고, 탄소성 모델로 가정한 유한요소해석을 적용하였다. 또한 인공시효와 같이 재료가 고온에서 장시간 유지되는 경우의 Zener-Wert-Avrami 함수를 적용하여 잔류응력 변화를 확인하였다. 잔류응력의 측정은 X 선 회절법으로 측정하고 측정결과는 예측된 유한요소해석 결과와 비교하여 해석의 신뢰성을 확보하고 해석기법을 확립하였다.

The purpose of this study is to predict the residual stress in Al6061 during T6 heat treatment. In this study, the variable residual stress in case of the solid solution($530^{\circ}C$, 2h) and artificial ageing($175^{\circ}C$, 9h) of Al6061 subjected to T6 heat treatment is determined at different ageing times. A heat treatment experiment is conducted to determine the heat transfer coefficient, on the basis of which the residual stress during the T6 heat treatment is predicted. In order to take into account the relaxation of residual stress during artificial ageing, a Zener-Wert-Avrami function is used and elasto-plastic nonlinear analysis is conducted through FE-simulation. Further, the residual stress is measured by using the X-ray diffraction(XRD) method, and the result is compared with the result from the FE-simulation. It is found that the residual stress predicted form the FE-simulation is in good agreement with the residual stress measured by using the XRD method.

키워드

참고문헌

  1. Jang, H. S., 1997, "The Handbook of Advanced Aluminum Technology," Hanlimwon.
  2. Kang, D. H., Lee, B. J., Yun, C. B. and Kim, K. W., 2010, "Study on Torsional Strength of Induction-Hardened Axle Shaft," Transactions of the KSME A, Vol. 34, No. 5, pp. 645-649. https://doi.org/10.3795/KSME-A.2010.34.5.645
  3. Rogante, M., Battistella, P. and Rustichelli, F., 2004, "Residual Stress Measurement by Neutron Diffraction in AA6082 Extruded Samples Submitted to Different Quenching Rates," Journal of Alloys and Compounds, Vol. 378, pp.335-338. https://doi.org/10.1016/j.jallcom.2003.12.049
  4. Ian, M., 2004, "Residual Stress Reduction During Quenching of Wrought 7075 Aluminum Alloy," Master's Thesis.
  5. Muammer, K., John, C. and Taylan, A., 2006, "Prediction of Residual Stress in Quenched Aluminum Block and Their Reduction through Cold Working Processed," Journal of Materials Processing Technology, Vol.174, pp. 342-354. https://doi.org/10.1016/j.jmatprotec.2006.02.007
  6. Hossain, S., Truman, C. E., Smith, D. J., Peng, R. L. and Stuhr, U., 2007, "A Study of the Generation and Creep Relaxation of Triaxial Residual Stresses in Stainless Steel," International Journal of Solid and Structure, Vol. 44, pp. 3004-3020. https://doi.org/10.1016/j.ijsolstr.2006.09.001
  7. Juijerm, P. and Altenberger, I., 2006, "Residual Stress Relaxation of Deep-Rolled Al-Mg-Si-Cu Alloy during Cyclic Loading at Elevated Temperature," Scripta Materialia, Vol. 55, pp. 1111-1114. https://doi.org/10.1016/j.scriptamat.2006.08.047
  8. Juijerm, P., Altenberger, I. and Scholtes, B., 2007, "Influence of Ageing on Cyclic Deformation Behavior and Residual Stress of Deep Rolled As-Quenched Aluminum Alloy AA6110," International Journal of Fatigue, Vol. 29, pp. 1374-1382. https://doi.org/10.1016/j.ijfatigue.2006.10.008
  9. Simsir, C. and Gur, C. H., 2008, "3D FEM Simulation of Steel Quenching and Investigation of the Effect of Asymmetric Geometry on Residual Stress Distribution," Journal of Materials Processing Technology, Vol. 207, pp. 211-221. https://doi.org/10.1016/j.jmatprotec.2007.12.074
  10. Berger, M. C. and Gregory, J. K., 1999, "Residual Stress Relaxation in Shot Peened Timetal 21s," Materal Science and Engineering A, Vol. 263, pp. 200-204. https://doi.org/10.1016/S0921-5093(98)01165-4
  11. Alberg, H. and Berglund, D., 2003, "Comparison of Plastic, Viscoplatic and Creep Models when Welding and Stress Relief Heat Treatment," Computer Methods in Applied Mechanics and Engineering, Vol. 192, pp. 5189-5208 https://doi.org/10.1016/j.cma.2003.07.010

피인용 문헌

  1. Relief of Residual Stress and Estimation of Heat-Treatment Characteristics for Al6061 Alloy by Cryogenic Heat Treatment vol.35, pp.10, 2011, https://doi.org/10.3795/KSME-A.2011.35.10.1145