A Study on Fracture Surface of Aged Turbine by Fractal Dimension

  • Kim, Amkee (Department of Mechanical Engineering Kongju National University) ;
  • Nahm, Seung-Hoon (Korea Research Institute of Standards and Science Taejon)
  • Published : 2001.10.01

Abstract

Since fracture surface presents clear evidence to describe the circumstances of material failure event, analysis of fracture surface should provide plenty of useful information for failure prevention. Thus if we extract proper information from the fracture surface, the safety evaluation, for plant component could be more accurate. In general, the chaotic morphology of fracture surface is determined by the degree of material degradation as well as by other factors such as type of load, geometry of specimen, notch condition, microstructure of material and environment. In this research, we developed a fractal analysis technology for the fracture surface of aged turbine rotor steel based on the slit-island technique using an image analyzer. Moreover the correlation between the fractal dimension and the aging time was studied.

Keywords

References

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