Issue 48

A.C. de Oliveria Miranda et alii, Frattura ed Integrità Strutturale, 48 (2019) 611-629; DOI: 10.3221/IGF-ESIS.48.59 628 C ONCLUSIONS he transition of 2D part-through cracks (such as surface or corner flaws) to 1D through-cracks was modeled based on Newman-Raju’s SIF equations for 2D elliptical cracks. The proposed interpolation equations were applied to describe the fatigue crack growth behavior of both surface and corner cracks on rectangular plates. The resulting continuous expressions were shown to better model not only the back face magnification and crack shape effects, but also the influence of the specimen width and front surface on the growth of part-through cracks. In addition, the proposed equations guarantee continuity of the SIF expressions between the transitioning period and the through-crack growth regime, as well as being able to reproduce the observed “catch up effect.” Comparison with experimental results showed that the proposed equations are able to reasonably represent the global behavior of the 2D-1D crack transitions. R EFERENCES [1] ASM Handbook, v.12, 9 th ed., Fractography, ASM 1987. [2] Castro, J.T.P., Giassoni, A., Kenedi, P.P. (1998). Fatigue propagation of semi and quart-elliptical cracks in wet welds. J Braz Soc Mech Sci Eng 20, pp.263-277 (in Portuguese). [3] Meggiolaro, M.A., Miranda, A.C.O., Castro, J.T.P., (2007). Short crack threshold estimates to predict notch sensitivity factors in fatigue. Int J Fatigue 29, pp. 2022–2031. [4] Castro, J.T.P., Landim, R.V., Leite, J.C.C., Meggiolaro, M.A. (2015). Prediction of notch sensitivity effects in fatigue and EAC. Fatigue Fract Eng Mater Struct 38, pp. 161-179. [5] Góes, R.C.O., Castro, J.T.P., Martha, L.F. (2014). 3D effects around notch and crack tips. Int J Fatigue 62, pp. 159- 170 [6] Pook, L.P. (1994). Some Implications of Corner Point Singularities. Eng Fracture Mech 48(3), pp. 367-378. [7] Tada, H., Paris, P.C., Irwin, G.R. (2000). The Stress Analysis of Cracks Handbook, 3rd ed. Wiley. [8] Murakami, Y. (1987). Stress Intensity Factors Handbook. Pergamon. [9] Anderson, T.L. (2005). Fracture Mechanics, 3 rd ed., CRC. [10] Castro, J.T.P., Meggiolaro, M.A. (2016). Fatigue Design Techniques v. 3: Crack Propagation, Temperature and Statistical Effects. CreateSpace 2016. [11] Broek, D. (1989). The Practical Uses of Fracture Mechanics, Kluwer. [12] Grandt, A.F., Harter, J.A., Heath, B.J. (1994). Transition of part-through cracks at holes into through-the-thickness flaws. ASTM STP 833, pp. 7-23. [13] Rifani, A.I., Grandt, A.F. (1996). A fracture mechanics analysis of fatigue crack growth in a complex cross section. Eng Failure Analysis 3, pp. 249–265. [14] Meggiolaro, M.A., Castro, J.T.P. (2010). Automation of the fatigue design under variable amplitude loading using the ViDa software. Int J Struct Integrity 1, pp. 94-103. [15] Fawaz, S.A. (1997). Fatigue crack growth in riveted joints. Delft University Press. [16] Johnson, W.S. (1979). Prediction of constant amplitude fatigue crack propagation in surface flaws. ASTM STP 687, pp. 143-155. [17] Hall, L.R., Shah, R.C., Engstrom, W.L. (1974). Fracture and fatigue crack growth behavior of surface flaws and flaws originating at fastener holes. A.F.F.D. Laboratory. [18] Newman Jr, J.C. (1979). A review and assessment of the stress-intensity factors for surface cracks. ASTM STP 687, pp. 16-46. [19] Raju, I.S., Newman Jr, J.C. (1979). Stress-intensity factors for a wide range of semi-elliptical surface cracks in finite- thickness plates. Eng Fract Mech 11, pp. 817-829. [20] Newman Jr, J.C., Raju, I.S. (1983). Stress-intensity factor equations for cracks in three-dimensional finite bodies. ASTM STP 791, pp. 238-265. [21] Newman Jr, J.C., Raju, I.S. (1984). Stress-intensity factor equations for cracks in three-dimensional finite bodies subjected to tension and bending loads. NASA TM-85793. [22] Raju, I.S., Atluri, S.N., Newman Jr, J.C. (1988). Stress-intensity factors for small surface and corner cracks in plates. NASA TM-100599. [23] Carpinteri, A., Brighenti, R., Spagnoli, A. (1988). Part-through cracks in pipes under cyclic bending. Nuclear Engineering and Design 185, pp. 1-10. T