Resumo

SAENZ P, LAURA A; HILDERS, OSWALDO A; HERGUETA, RUBEN D  e  ZABALA, EINALDO A. Estudio de un acero inoxidable dúplex saf 2507 sometido a un tratamiento térmico de envejecimiento a una temperatura de 850 ºc por tiempos entre 1 hora y 48 horasMicrostructural study with thermal aging treatment at 850 ºc on duplex stainless steel saf 2507 between 1h and 48 h. Rev. Fac. Ing. UCV [online]. 2007, vol.22, n.3, pp.21-30. ISSN 0798-4065.

This study concerns a duplex stainless steel SAF 2507 subjected to ageing treatment at 850 C for periods of r 0,5, 1, 5, 24, and 48 hours. Mechanical behaviour was evaluated through tension tests, charpy V notch impact energy and hardness (HV) tests. The study of the microstructure and the fracture surface of the material was performed using optical and Scanning Electronic Microscopy (SEM). Of the results obtained in the different mechanical tests, changes were observed in the mechanical properties of the material as a result of the thermal aging treatment. In the evaluation of the material toughness, it was seen to be very low in the thermally treated conditions, but more impact toughness was observed in the original condition. From the results obtained of the mechanical testing, the presence of the sigma phase is presumed, and with the study of the microstructures it was observed that the material after being treated thermally becomes fragile, this being an effect generated by the sigma phase, which, at the same time, decreases the toughness of the material.

Palavras-chave : Duplex Stainless Steel; Aging treatment; Sigma phase; Impact toughness; Embrittlement.