Heon-Young Ha

Isothermal Decomposition of Ferrite in a High-Nitrogen, Nickel-Free Duplex Stainless Steel

The formation and crystallography of second phases during isothermal decomposition of ferrite (α) in a high-nitrogen, nickel-free duplex stainless steel was examined by means of transmission electron microscopy (TEM). At an early stage of aging, the decomposition of α started along the α/γ phase boundaries where sigma (σ) phase and secondary austenite (γ2) precipitated in the form of an alternating lamellar structure. The combined analyses based on the simulation of diffraction patterns and stereographic projection have shown that most of the σ phase was related to the γ2 by the following relation:

Effects of Nitrogen and Tensile Direction on Stress Corrosion Cracking Susceptibility of Ni-Free FeCrMnC-Based Duplex Stainless Steels

(111)_{\gamma } \parallel (001)_{\sigma }

Effect of W on stress corrosion cracking susceptibility of newly developed Ni-saving duplex stainless steels

and

Investigation of the Localized Corrosion and Passive Behavior of Type 304 Stainless Steels with 0.2–1.8 wt % B

[10\bar{1}]_{\gamma } \parallel [110]_{\sigma } .

Effects of Cr2N on the pitting corrosion of high nitrogen stainless steels

The intergranular and intragranular precipitation of Cr2N with trigonal structure were identified, and the orientation relationships (ORs) with α and γ matrix could be expressed as