Corrosion and microstructural analysis data for AISI 316L and AISI 347H stainless steels after exposure to a supercritical water environment
This article presents corrosion data and microstructural analysis data of austenitic stainless steels AISI 316L and AISI 347H exposed to supercritical water (25 MPa, 550 °C) with 2000 ppb of dissolved oxygen. The corrosion tests lasted a total of 1200 h but were interrupted at 600 h to allow measurements to be made. The microstructural data have been collected in the grain interior and at grain boundaries of the bulk of the materials and at the superficial oxide layer developed during the corrosion exposure.
Effect of exposure temperature on the corrosion behaviors of TP347H austenitic stainless steel in supercritical water
Abstract Corrosion behaviors of TP347H austenitic stainless steel were investigated in supercritical water at different temperatures. Results show that weight gains follow roughly parabolic kinetics except after 1800 h exposure at 650 °C. Some outer isolated Fe2O3 particles are interspersed on the inner nano-sized spinel scale at 380 °C. At 550 °C, the oxide layer with outer magnetite and inner spinel gradually increases and the (Fe,Cr)2O3 layer decreases with exposure time increasing. At 650 °C, the thick magnetite layer is firstly formed and then spalled associating with a chromia layer generated at the spinel/matrix interface, resulting in significant weight loss.
Numerical analysis of deterioration phenomena in heat transfer to supercritical water
Abstract Deterioration in heat transfer at supercritical water cooling in a vertical pipe is numerically analyzed. The calculation is based on a parabolic solver for steady-state equations in r−z two dimensions, a k−ϵ model for turbulence and a steam table library for physical properties of supercritical water. Calculation results agree with the experimental data of Yamagata et al. It is found that heat transfer deterioration is caused by two mechanisms depending on the flow rate. When the heat flux is increased much above the deterioration heat flux, a violent oscillation is observed in the temperature distribution.