Acta Metallurgica Sinica (English Letters) ›› 1993, Vol. 6 ›› Issue (12): 453-458.

• Research paper • Previous Articles     Next Articles

AN APPLICATION OF SPI TECHNIQUE FOR STUDING STRA DISTRIBUTION AT CRACK TIP

WEI Xuejun ZHOU Xiangyang LI Jin LIU Guanglei KE Wei Corrosion Science Laboratory,Academia Sinica,Institute of Corrosion and Protection of Metals,Academia Sinica,Shenyang,China Institute of Corrosion and Protection of Metals,Academia Sinica,Shenyang 110015,China   

  • Received:1993-12-11 Revised:1993-12-11 Online:1993-12-11 Published:2009-10-10

Abstract: A computerized digital speckle-interferometry(SPI)system has been set up to determine the in-plane distribution of displacement and strain at crack tip of CF specimens.The principle and the experimental method of this technique are described in detail.The effect of corrosion factors on plastic deformation at crack tip in CF process has been examined by comparing the near-tip strain fields of steel A537 before and after hydrogen charging,and of pure copper before and after applying an anodic current in 3.5% NaCl. The results shows that the clasic finite element mathematical models are not suitable to describe the near-tip deformation under the experimental conditions.Hydrogen charging made the crack tip plasticity decreased for steel A537 and the anodic dissolution enhance the near tip deformation of pure copper specimen.

Key words: speckle-interferometry, corrosion fatigue, crack tip deformation