Abstract
The values of fracture toughness K 1C of C-Mn steels and weld metal were calculated from values of COD measured in standard specimens tested at low temperatures. The analysis of scattering of 42 values of K 1C measured in normalized C-Mn steel showed that the highest value of K 1C could be as large as 360 percent of the lowest. The factors affecting the scattering were investigated in detail and it was found that the scattering was mainly caused by the variation of locations of cleavage initiation. The local fracture stress σ\(_f \) was found to be the most stable parameter and combined with the minimum cleavage distance \(Xf \) min which is determined by the triaxiality of stress reaching a critical value, it could be used to characterize the lower boundary of fracture toughness of steels.
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Chen, J., Wang, G. On scattering of measured values of fracture toughness parameters. International Journal of Fracture 94, 33–50 (1998). https://doi.org/10.1023/A:1007560230357
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DOI: https://doi.org/10.1023/A:1007560230357