Autor: |
Masood Chaudry U; School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 16419, Korea., Ahmad HW; School of mechanical Engineering, Sungkyunkwan University, Suwon 16419, Korea., Tariq MR; Department of Metallurgy and Materials Engineering, University of the Punjab, Lahore 54590, Pakistan., Farooq A; Department of Metallurgy and Materials Engineering, University of the Punjab, Lahore 54590, Pakistan., Khan MK; School of Chemical Engineering, Sungkyunkwan University, Suwon 16419, Korea.; SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Korea., Sher F; School of Mechanical, Aerospace and Automotive Engineering, Faculty of Engineering, Environmental and Computing, Coventry University, Coventry CV1 5FB, UK., Zeb H; Institute of Energy & Environmental Engineering, University of the Punjab, Lahore 54590, Pakistan., Hamad K; School of Advanced Materials Science & Engineering, Sungkyunkwan University, Suwon 16419, Korea. |
Abstrakt: |
In the present study, the effect of post weld heat treatment (PWHT) on the microstructure and corrosion kinetics of butter welded Nickel Alloy 617 and 12Cr steel was investigated. Buttering was carried out on the 12Cr side with the Thyssen 617 filler metal. Furthermore, post weld heat treatment (PWHT) was conducted at 730 °C with a holding time of 4 h followed by furnace cooling. Optical Microscopy (OM) was conducted to study the microstructural evolution in dissimilar material welding as a result of PWHT. Moreover, Scanning Electron Microscopy with energy dispersive spectroscopy (SEM-EDS) was employed to determine the elemental concentrations in all important regions of the butter weld before and after the PWHT. In addition, the effect of PWHT on the corrosion kinetics of the butter weld was also investigated by potentiodynamic polarization measurements in 5 wt.% NaCl + 0.5 wt.% CH 3 COOH electrolyte at room temperature, 30 °C, 50 °C and 70 °C. The corrosion activation parameters were also determined for both the samples by using Arrhenius plots. The results revealed the higher susceptibility of corrosion of the butter weld after PWHT, which was attributed to the reduced Cr content in the heat affected zone of the 12Cr region due to the sensitization effect of the heat treatment, resulting in higher corrosion rates. |