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V. Di Cocco et alii, Frattura ed Integrità Strutturale, 34 (2015) 415-421; DOI: 10.3221/IGF-ESIS.34.46 421 is characterized by large grains (about 600  m), considering the fatigue crack propagation results and the SEM fracture surface analysis, the following conclusions can be summarized: - The investigated SMA is characterized by a stress-induced transformation. - Investigated SMA fatigue crack propagation resistance is strongly affected by the microstructure peculiarities (e.g., grain size) and by the stress induced microstructural transformations. The presence of a plateau in the da/dN-  K results (for the lower R values) is probably related to transition conditions (crack tip plastic zone that become larger than grains size + increase of the importance of the microstructure transformation); - Martensitic transformation becomes more and more important with the increase of the R and/or  K values. Corresponding to the more critical conditions (highest R and  K values) higher crack growth rates correspond to an increase of the cleavage and of intergranular secondary cracks on the fracture surface. R EFERENCES [1] Suzuki, T., Kojima, R., Fujii, Y., Nagasawa, A.,. Reverse transformation behaviour of the stabilized martensite in Cu10at%Zn19at%Al alloy. Acta Metall. 37 (1989) 163–168. [2] Di Cocco, V., Iacoviello, F., Natali, S., Two Cycles deformation effects on NiTi pseudoelastic alloy microstructure, In: IGF Workshop proceedings, Forni di Sopra, Italy, (2012) 62-67. [3] Di Cocco, V., Iacoviello, F., Natali, S., Volpe, V., Fatigue crack behavior on a Cu-Zn-Al SMA, Frattura ed Integrità Strutturale, 30 (2014) 454-461; DOI: 10.3221/IGF-ESIS.30.55 [4] Ma, J., Karaman, I., Noebe, R.D., High Temperature Shape Memory Alloys. International Materials Reviews, 55(5) (2010) 257-315. [5] Otsuka, K., Ren, X., Physical metallurgy of Ti–Ni-based shape memory alloys. Progress in Materials Science, 50 (2005) 511-678. [6] Asanovic, V., Delijic, K., Jaukovic, N., A study of transformation of β-phase in Cu-Zn –Al shape memory alloys. Scripta Materialia, 58 (2008) 599-601. [7] Volpe, V., Realizzazione e caratterizzazione di leghe a memoria di forma a base rame, Ph.D. thesis, University of Rome “Sapienza”, (2013). [8] ASTM E407-07, Standard Practice for Microetching Metals and Alloys, ASTM International. [9] Di Cocco, V., Iacoviello, F., Tomassi, L., Rossi, A., Natali, S., Volpe, V., Crack path in a Cu-Zn-Al PE alloy under uniaxial load, Acta Fracturae, (2013) 255-261. [10] PowderCell 2.3 handbook: Pulverdiffraktogrammeaus Einkristalldaten und Anpassungexperimenteller Beugungsaufnahmen. Available at http://www.bam.de/de/service/publikationen/powder_cell.htm. [11] ASTM E 647-08, “Standard Test Method for Measurement of Fatigue Crack Growth Rates”, ASTM International. [12] Maletta, C., Furgiuele, F., Fracture control parameters for NiTi based shape memory alloys, International Journal of Solids and Structures, 48 (2011) 1658–1664.