PINHO EMYGDIO, GUILHERME ZEEMANN ; SANTOS DE ASSIS, KIOSHY ; ZEEMANN, ANNELISE ; MATTOS, OSCAR ROSA .
Resumo: This paper presents the corrosion test results of 9% Ni steels (ASTM A522 type 1 and ASTM A333 grade 8) in presence of aqueous solutions containing H2S and CO2. A forged bar and a seamless pipe, manufactured to be used in high-pressure CO2 lines, were tested by NACE TM0177, TM0284, and ISO 7539-2. Localized corrosion and cracks were observed in the sulfide stress cracking (SSC) tests, in both base materials, and welded joint. These types of attack were associated to specific metallurgical features of the products (forged bar and seamless pipe), indicating that a better evaluation of the corrosion resistance of these materials is necessary. No hydrogen induced cracking damage was detected after the standard testing time, but microcracks were identified, reducing the impact energy levels. The welded joint presented high susceptibility to SSC cracking.
