DOI QR코드

DOI QR Code

Rotary Bending Fatigue Characteristics According to Optimal Friction Welding of SF45 to SM45C Steel Bars

SF45와 SM45C의 마찰용접 최적화에 따른 회전굽힘피로 특성

  • Kong, Yu Sik (Dept. of Mechanical Engineering, Pukyong Nat'l Univ.) ;
  • Park, Young Whan (Dept. of Mechanical Engineering, Pukyong Nat'l Univ.)
  • 공유식 (부경대학교 기계공학과) ;
  • 박영환 (부경대학교 기계공학과)
  • Received : 2016.06.20
  • Accepted : 2016.11.22
  • Published : 2017.03.01

Abstract

A study on dissimilar friction-welded joints was performed for cam shaft applications using solid bar samples, 20mm in diameter, of forging steel(SF45) and carbon steel(SM45C). The main parameters of friction welding such as tensile tests, Vickers hardness surveys of the bond of area, the heat affected zone (HAZ), and the observation of microstructure were investigated to ensure a good quality of friction welding through visual observations. The specimens were tested as-welded and post weld heat treatment(PWHT). This paper deals with optimizing the welding conditions and analyzing various rotary bending fatigue test(RBFT) properties about heat-treated base metal(BM), as-welded and PWHT. Consequently, two materials for friction welding are strongly mixed with a well-combined structure of micro-particles without any molten material, particle growth, or any defect. Moreover, the fatigue limit of BM(SF45) and PWHT for the RBFT were observed as 180MPa and 250MPa, respectively. It was confirmed that the PWHT causes approximately 40% improvement in the fatigue limit when compared to the BM(SF45).

Keywords

Rorary Bending Fatigue Test;Post Weld Heat Treatment;Base Metal;Welding Condition;Fatigue Limit

References

  1. Cho, H. S. and Suh, S. J., 1997, "Friction Welding of Inconel 713C and SCM440," Journal of KWS, Vol. 15, No. 6, pp. 78-84.
  2. Oh, S. K., Kim, B. A., Kim, S. J. and Nam, S. H., 1988, "A Study on Friction Welding of SM45C to SCM4 Steel Bars and the Fatigue Properties," Journal of KSOE, Vol. 2, No. 2, pp. 312-321.
  3. Kong, Y. S., Yoon, S. P. and Kim, S. J., 2010, "Mechanical Properties of Friction Welded SM45CSF45 Joints for Automobile Reverse Idle Gear Shaft Applications," Journal of KSME-A, Vol. 34, No. 1, pp. 85-90.
  4. Kong, Y. S. and Kim, S. J., 2006, "Mechanical Properties of Dissimilar Friction Welded Steel Bars in Relation to Post Weld Heat Treatment," Trans. Korean Soc. Mech. Eng. A, Vol. 30, No. 4, pp. 402-408. https://doi.org/10.3795/KSME-A.2006.30.4.402
  5. Suh, M. S., Fean, Y. S. and Suh, C. M., 2012, "Variation of Fatigue Properties in Nanoskinned Ti-6Al-4V-Rotating Bending and Axial Loading Tension-Compression Cycle," Trans. Korean Soc. Mech. Eng. A, Vol. 36, No. 4, pp. 443-449. https://doi.org/10.3795/KSME-A.2012.36.4.443
  6. Oh, K. K., Kim, J. H. and Choi, H. S., 2015, "Effect of Nitriding on Fatigue Characteristics of Cr-Mo Alloy Steel," Trans. Korean Soc. Mech. Eng. A, Vol. 39, No. 6, pp. 597-602. https://doi.org/10.3795/KSME-A.2015.39.6.597
  7. ASTM, 1981, "Statistical Analysis of Fatigue Data," ASTM-STP, p. 744.
  8. Jung, H.S., Cho, J.R., Oh, J.S. Kim, E.N. Choi, S.G. and Ha, M.Y., 2010, "Inertia Friction Welding Process Analysis and Mechanical Properties Evaluation of Large Rotor Shaft in Marine Turbo Charger," International Journal of Precision Engineering and Manufacturing, Vol. 11 No. 1, pp. 83-88.
  9. Sohn, H. J. and Kim, S. J., 2012, "Marco and Microscopic Observations of Fatigue Crack Growth Behavior in API2WGr.50 Steel Joints," Journal of Ocean Engineering and Technology, Vol. 26, No. 5, pp. 73-80. https://doi.org/10.5574/KSOE.2012.26.5.073
  10. Castillo, E., Fermansez, Canteli, A. and Hadi, A. S., 1999, "On Fitting a Fatigue Model to Data," International Journal of Fatigue, No. 21, pp. 97-106.
  11. Hanaki, S., Yamashita M. and Uchida, H., 2010, "On Stochastic Evaluation of S-N Data Based on Fatigue Strength Distribution," International Journal of Fatigue, Vol. 32, No. 3, pp. 605-609. https://doi.org/10.1016/j.ijfatigue.2009.06.001
  12. Fouchereau, R., Celeus, G. and Pamphile, P., 2014, "Probabilistic Modeling of S-N Curves," International Journal of Fatigue, No. 68, pp. 217-223.
  13. Zhai., J. M. and Li, X. Y., 2012, "A Methodology to Determine a Conditional Probability Density Distribution Surface from S-N Data," International Journal of Fatigue, No. 44, pp. 107-115.