SCC behaviours of austenitic stainless steel Z3CN20-09M in high temperature water

Abstract

Stress corrosion cracking (SCC) behaviours of Z3CN20-09M stainless steel in high temperature water containing Cl− were studied. The results indicated that SCC sensitivity was inconsistent with test temperature. The minimum and maximum of SCC sensitivity occurred at 320 and 290°C respectively, and SCC sensitivity at 250°C fell between them. SCC crack initiated preferentially at bottom of corrosion pit or along phase boundary between austenite and ferrite, and its propagation depended on relative orientation to the phase boundary. SCC crack parallel to the phase boundary propagated along the phase boundary, while that perpendicular to the phase boundary was hindered to propagate.

High-Resolution Characterisation of Austenitic Stainless Steel in PWR Environments: Effect of Strain and Surface Finish on Crack Initiation and Propagation

“…However, this does not seem to be the case for the material used for this study which cracks preferentially at the ferriteaustenite interface, representing ~50% of the cracks in both samples (for SSRT-T1 only propagation type has be considered since most of the cracks are initially transgranular but they become intergranular or follow a δ-γ interface after some penetration). Based on results from Y. H. Lu et al [20], this can be related to the sample orientation (S-L) used for this work that imply ferrite austenite interfaces are perpendicular to stress direction, i.e., δ -γ interfaces are parallel to crack propagation. This stimulates higher strain localisation at the interface (therefore, more cracks) in addition to the differences accommodating stresses between ferrite and austenite.…”

Experimental and numerical studies on the corrosion properties of AISI 316L stainless steel in two-phase upward slug flows

“…In an oxidizing environment, it will react with oxygen and form a passivation film on the surface to prevent further corrosion (Turnbull et al, 2003). However, in the petroleum industry, the fluid medium usually contains chloride ions, which can destroy the product scale film (Khan et al, 2002;Lu et al, 2014). Moreover, the medium is usually a twophase gas-liquid flow, which results in much more complicated flow characteristics than do single-phase flows.…”

Temperature influence on SCC behaviour of duplex stainless steel

“…11,12 SCC has been the subject of study in recent years for different materials, because of the enormous damage it causes in structures. [13][14][15][16][17][18][19][20][21][22][23][24][25][26] The susceptibility of DSSs to SCC has recently been studied by Laitinen and Hanninen 27 who investigated SCC susceptibility in a 50 wt-% CaCl 2 solution at 100°C for the UNS S31803 DSS. They observed that crack propagation was mainly through the austenite phase.…”