Cyclic behavior of DIN 1.4460 duplex stainless steel between room temperature and 773K

I ALVAREZ; A ARMAS; S HEREÑU; S DEGALLAIX; G DEGALLAIX

FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES (PRINT)

Blackwell

Año: 2003 vol. 26 p. 27 - 35

8756-758X

Cyclic tests performed in the temperature range 300 K - 773 K on duplex stainless steel DIN 1.4460 show that the cyclic stress-strain behaviour of this steel is strongly temperature dependent. At 300 and 473 K an almost constant peak tensile stress stage, is followed by a slight softening that continues up to failure in the case of 300 K, but by a secondary hardening at 473 K. Pronounced initial cyclic hardening followed by secondary hardening was the main feature of the temperature range between 573 and 723 K. At 773 K, after a weak hardening stage, a strong softening continues up to failure. The mechanical behaviour and the evolution of the microstructure were analysed, and the internal and the effective stresses were studied. It was found that the internal stress is responsible for the strong hardening that occurs in the intermediate temperature range and for the softening at 773 K.