Issue 43

B. Saadouki et alii, Frattura ed Integrità Strutturale, 43 (2018) 133-145; DOI: 10.3221/IGF-ESIS.43.10 142 (predominance of ∆ε p -N relation), and the yield strength and ultimate tensile strength at high cycle (predominance of ∆ ε el - N ). (a) (b) Figure 12 : Resistance fatigue curves for SICLANIC ® predicted using (a) four correlation point method and (b) a universal slopes method. ε f σ f (MPa) ε f ’ σ f ’ (MPa) b c Manson’s four points 0.29 793.35 0.19 931.71 -0.09 -0.46 Manson’s universal slopes 0.29 793.35 0.36 1168.5 -0.12 -0.6 Table 4 : Low cycle fatigue characteristics for the SICLANIC ® . Moreover, many researchers have linked coefficients b and c to the cyclic hardening coefficient n ’ , Tab. 5 shows some formulas results. Morrow has proposed the following relation:    ' 1 5 ' n b n (12)    1 1 5 ' c n (13) Tomkins [28] proposes on his side:    ' 1 2 ' n b n (14)    1 1 2 ' c n (15)