Dynamic embrittlement during fatigue of a Cu–Ni–Si alloy

Fatigue tests are performed on the Cu–2.16Ni–0.72Si alloy, at different stress ratios, R, at room temperature and 473 K. For R = 0.4 the fatigue strength decreases when temperature is increased. The observation of intergranular cracking on fracture surfaces shows that this phenomenon is related to dynamic embrittlement.

► In this work, dynamic embrittlement is studied during fatigue of a Cu–Ni–Si alloy.
► Under a positive load ratio, fatigue strength decreases with increasing temperature.
► Intergranular fracture proves grain boundary weakness due to dynamic embrittlement.
► Dynamic embrittlement causes a fatigue strength decrease, under positive load ratio.