Irradiation crack-arrest toughness

Key words fracture toughness, J-integral, master curve, irradiation, crack-arrest, embrittlement, Charpy impact, nil-ductility transition (NDT) temperature, pressurized water reactor (PWR). 

The crack arrest toughness (T a) can also be assessed from instrumented CVN data using the correlation developed between Tnh, and the temperature corresponding to the crack arrest force of 4kN. The method has been used for assessing crack arrest toughness of irradiated RPV steels from existing CVN data (Wallin, 2001). 

Effects of irradiation on dynamic fracture toughness and crack-arrest toughness... 

In comparison with initiation fracture toughness data, there are substantially fewer data on effects of irradiation on dynamic fracture toughness and crack-arrest toughness. Some early results of vs temperature are shown in Fig. 10.11 (Davidson et al, 1976), while more recent results of Ki are shown in Fig. 10.12 (Iskander et al, 1992). In general, the... 

Plots showing effects of irradiation on crack-arrest toughness, /C a, vs temperature for HSSI weld 73W, the same weld metal as in Fig. 10.9a (Iskander et al., 1992). 

Comparison of mean fracture toughness and crack-arrest toughness vs normalized temperature for HSSl welds 72 and 73W in (a) unirradiated and (b) irradiated conditions (Nanstad et al., 1995). 

Iskander S K, Corwin W R and Nanstad R K (1992), Effects of irradiation on crack-arrest toughness of two high-copper welds, pp. 251-269 in Effects of Radiation on Materials 15th International Symposium, ASTM STP1125, R E StoUer, A S Kumar and D S GeUes, eds, American Society for Testing and Materials, Philadelphia, PA. 

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